33 resultados para cardiac signals, EEG signals, analysis, higher order spectra


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In the existing literature, the existence conditions and design procedures for scalar functional observers are available for the cases where the observers’ order p is either p=1 or p=(v-1), where v is the observability index of the matrix pair (C,A). Therefore, if an observer with an order p=1 does not exist, the other available option is to use a higher order observer with p=(v-1). This paper shows that there exists another option that can be used to design scalar linear functional observers of the order lower than the well-known upper bound (v-1). The paper provides the existence conditions and a design procedure for scalar functional observers of order 0≤ p ≤2, and demonstrates the presented results with a numerical example.

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Teacher/Student engagement enriches learning experiences beyond the specifics of communicated information by encouraging connectivity and the fostering of learning communities. This paper is an analysis of student engagement in a postgraduate online-mediated learning environment, and considers how engagement may be an important factor in building communities of learning in conjunction with improved learning outcomes. This paper is informed by the conceptual framework for effective e-learning outlined by Garrison and Anderson (2003) as necessary for higher order knowledge building by students as part of skills development for participation in knowledge economies. Data collected through a pilot study infers that a correlation exists between the development of small groups of significantly contributing students within wider online student cohorts and the learning outcomes of all students within the cohort. The findings indicate that a number of small events have increased student engagement and motivation, and resulted in improved learning outcomes.

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We analyse the wood and concrete designs of the Wälludden building described by Börjesson et al. (Energy Policy 28 (2000) 575) in terms of their embodied energy, employing an environmentally extended input–output framework in a tiered hybrid life-cycle assessment, and in a structural path analysis. We illustrate the complexity of the inter-industry supply chains underlying the upstream energy requirements for the building options, and demonstrate that higher-order inputs are difficult to capture in a conventional process analysis. Our calculations show that Börjesson and Gustavsson's estimates of energy requirements and greenhouse gas emissions are underestimated by a factor of about 2, and that corresponding greenhouse gas balances are positive at about 30 t C-eq. Nevertheless, Börjesson and Gustavsson's general result—the concrete-framed building causing higher emissions—still holds.

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We present an input-output analysis of the life-cycle labor, land, and greenhouse gas (GHG) requirements of alternative options for three case studies: investing money in a new vehicle versus in repairs of an existing vehicle (labor), passenger transport modes for a trip between Sydney and Melbourne (land use), and renewable electricity generation (GHG emissions). These case studies were chosen to demonstrate the possibility of rank crossovers in life-cycle inventory (LCI) results as system boundaries are expanded and upstream production inputs are taken into account. They demonstrate that differential convergence can cause crossovers in the ranking of inventories for alternative functional units occurring at second-and higher-order upstream production layers.

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A large amount of finite elements have been developed for finite element analysis of laminated composite plates. The laminated plate theories are reviewed and summarized in this paper. The focus of this review is on the recently developed laminated finite elements since 1990. The 2-D triangular and quadrilateral displacement-based and mixed/hybrid-based finite element models, which were developed based on the first-order shear deformation theories, the higher-order shear deformation theories, the zig-zag theories and the global-local higher-order deformation theories, and the layer-wise laminated plate theories are reviewed in this paper and also their related patents. Finally, some points on the development of the laminated finite elements are summarized.

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The main purpose of this study was to investigate the instructional interactive multimedia (IMI) production processes of adult novice multimedia production course. The study aimed at discovering whether a constructivistic teacher-learning environment facilitated these multimedia novice designer / producers to further develop metacognitivestates of higher-order thinking like schema formation, problem-solving and cognitive construction when producing their interactive multimedia project. To achieve this study examined the facilitative and limiting activities in planning, design and development that have assisted or hindered the NMDPs during their multimedia production work This research utilises a qualitative paradigm and makes extensive use of multiple data sources such as the participants’ proposals, planning aids, logs and final projects for single as well as cross-case analyses and discussion. Three cases were selected for in-depth analysis in the study because they provided interviews and more complete documentation and "thick descriptions" of their multimedia production activities. Findings about the NMDPs multimedia production endeavours showed that they learnt best about multimedia technology for teacing and learning by producing an interactive multimedia project themselves. Factors that enabled some of the NMDPs to flourish in a constructivistic environment included their ability to utilise their new and extended schemata to problem solve, their self regulation and a creative and positive attitude to demanding multimedia work NMDPs who utilised facilitative planning aids and design strategies produced impressive work. The study further indicates that the NMDPs’ holistic multimedia production experience made them aware of the levels of complexity involved and boosted their confidence about multimedia production for educational purposes. Suggestions for further research include examining the production styles of adult multimedia novices and young novices and investigating the implications of designing multimedia for large audience presentation rather than for single or small group learner usage.

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Despite the applied importance of cohesion within organisational settings, researchers have yet to reach consensus about the dimensionality of group cohesion, and therefore appropriate tools for its measurement. The way that cohesion has generally been conceptualised has changed over time, but the measures appear not to reflect the underlying theory. This deficiency has impeded attempts to explore the relationship between co-worker cohesion and group performance (Beal et al., 2003; Mullen & Copper, 1994). Given inconsistent findings from previous factor analyses of cohesion, the present study employed exploratory means to help clarify the factor structure of cohesion within the workplace. Potential participants were recruited via the researchers' social networks. This snowballing technique led to 236 participants completing the online questionnaire. Exploratory factor analysis revealed four first-order factors of team commitment, friendliness, interpersonal conflict and communication that collectively accounted for 55.17% of the variance shared among the 75 cohesion items. Subsequently, a single higher-order factor was extracted which accounted for over half of the co-variation among the first order factors. This higher-order factor seems to reflect a general cohesion factor, as it was loaded by a diffuse collection of items, including those from the four lower-order factors as well as items that failed to load onto these lower-order factors. While there were similarities between these results and those of previous studies, the present factor structure did not map perfectly onto any of the existing conceptual models of cohesion. This finding highlights the need to incorporate some alternate factors that have previously been given little consideration.

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The complex exponential basis expansion model (CE-BEM) provides an accurate description for the time-varying (TV) channels encountered in mobile communications. Many blind channel identification and equalization approaches based on the CE-BEM require precise knowledge of the basis frequencies of TV channels. Existing methods for basis frequency estimation usually resort to the higher-order statistics of channel outputs and impose strict constraints on the source signal. In this paper, we propose a novel method to estimate the basis frequencies for blind identification and equalization of time-varying single-input multiple-output (SIMO) finite-impulse-response (FIR) channels. The proposed method exploits only the second-order statistics of channel outputs and does not require strong conditions on the source signal. As a result, it exhibits superior performance to the existing basis frequency estimation methods. The validity of our method is demonstrated by numerical simulations.

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The overall aim of the Improving Middle Years Mathematics and Science (IMYMS) project was to explore the explore the nature and significance of subject cultures in framing teacher and school practice in mathematics and science and to develop a middle years school improvement model that takes account of these subject cultures in influencing school and teacher change. The project also investigated ways in which effective pedagogies in mathematics and science can be monitored; and ways in which higher order learning outcomes in mathematics and science can be reliably assessed.

The project has worked with more than 30 schools in four clusters to support them in planning for and implementing change. A framework describing effective mathematics and science pedagogies was developed, and used as the basis for auditing procedures that track classroom practice. Instruments were developed and used to probe: teacher classroom practice; student perceptions of classroom practice and learning preferences; knowledge outcomes; reasoning in science and mathematics; understanding of the nature of science and mathematics; and performance skills in mathematics and science investigations. Data sources have also included questionnaire data, interviews, school reports and field notes. Video data was also collected and used for stimulated recall interviews concerning teacher beliefs and practices.

In order to support teachers and schools to improve their practice, the project team worked with cluster educators in each of the clusters, and with school coordinators, through a number of network meetings including an initial ‘leading change’ workshop, through cluster visits, and the provision of auditing and planning instruments supported by data analysis support. The nature of the subject cultures of, and effective pedagogies in, mathematics and science, was explored using interview data with effective teachers, literature exploration, interviews with project teachers to map characteristics of their practice, the team’s experience of the construction and analysis of achievement tests, a video and interview study of teachers of mathematics and science, and student perceptions data.

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In this paper we evaluate the intertemporal pricing performance of stock return determinants over the periods surrounding, and outside of, financial crises. The analysis focuses on the variables of size, book-to-market ratio, momentum, liquidity, and higher-order systematic co-moments. The evidence reveals that over non-crisis periods the market beta plays an important role in determining the cross-section of stock returns. Size, value, momentum, and liquidity also exhibit associations with the cross-section of stock returns. However, over crisis periods most of the variables we examined lose their explanatory power, suggesting that their usefulness is limited for investment purposes when financial markets experience crises. There is some evidence of coskewness pricing surrounding market crashes. Practitioners may consider coskewness over crisis periods.

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Qualitative and quantitative methods were used in this research to distinguish the prevailing D/discourses (words, tools, beliefs, thinking styles) in police training and to analyse the ‘discourse-practice’ (Cherryholmes 1988, p.1) framework of policing in a training environment. The manifestations, functions and consequences of the D/discourses raise concerns about the efficacy of training (its doctrinal intent and value versus its educative intent and value) and its implications for individuals’ identity, subjectivity, agency, learning, and “membership” within the policing community. The literature revealed that police training acts as a formally sanctioned vehicle for police culture, subcultures, and D/discourses. This is complicated by (a) the predominance of pedagogical training practices that support a trainer-centred approach and standardised lecture format for training, (b) police training focusing predominantly on law enforcement at the cost of higher-order conceptual skills, and (c) Australian and international studies of police management education which reveal a subculture resistant to theoretical analysis and critical reflection, and a set of unconscious and unchallengeable assumptions regarding police work, conduct, and leadership. A backdrop to this research and findings is the agenda of Australian and New Zealand police services for police to become a profession.

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 Many researchers have argued that higher order models of personality such as the Five Factor Model are insufficient, and that facet-level analysis is required to better understand criteria such as well-being, job performance, and personality disorders. However, common methods in the extant literature used to estimate the incremental prediction of facets over factors have several shortcomings. This paper delineates these shortcomings by evaluating alternative methods using statistical theory, simulation, and an empirical example. We recommend using differences between Olkin-Pratt adjusted r-squared for factor versus facet regression models to estimate the incremental prediction of facets and present a method for obtaining confidence intervals for such estimates using double adjusted-. r-squared bootstrapping. We also provide an R package that implements the proposed methods.

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Arboreal marsupials play an essential role in ecosystem function including regulating insect and plant populations, facilitating pollen and seed dispersal and acting as a prey source for higher-order carnivores in Australian environments. Primarily, research has focused on their biology, ecology and response to disturbance in forested and urban environments. We used presence-only species distribution modelling to understand the relationship between occurrences of arboreal marsupials and eco-geographical variables, and to infer habitat suitability across an urban gradient. We used post-proportional analysis to determine whether increasing urbanization affected potential habitat for arboreal marsupials. The key eco-geographical variables that influenced disturbance intolerant species and those with moderate tolerance to disturbance were natural features such as tree cover and proximity to rivers and to riparian vegetation, whereas variables for disturbance tolerant species were anthropogenic-based (e.g., road density) but also included some natural characteristics such as proximity to riparian vegetation, elevation and tree cover. Arboreal marsupial diversity was subject to substantial change along the gradient, with potential habitat for disturbance-tolerant marsupials distributed across the complete gradient and potential habitat for less tolerant species being restricted to the natural portion of the gradient. This resulted in highly-urbanized environments being inhabited by a few generalist arboreal marsupial species. Increasing urbanization therefore leads to functional simplification of arboreal marsupial assemblages, thus impacting on the ecosystem services they provide.

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Common dolphins, Delphinus sp., are one of the marine mammal species tourism operations in New Zealand focus on. While effects of cetacean-watching activities have previously been examined in coastal regions in New Zealand, this study is the first to investigate effects of commercial tourism and recreational vessels on common dolphins in an open oceanic habitat. Observations from both an independent research vessel and aboard commercial tour vessels operating off the central and east coast Bay of Plenty, North Island, New Zealand were used to assess dolphin behaviour and record the level of compliance by permitted commercial tour operators and private recreational vessels with New Zealand regulations. Dolphin behaviour was assessed using two different approaches to Markov chain analysis in order to examine variation of responses of dolphins to vessels. Results showed that, regardless of the variance in Markov methods, dolphin foraging behaviour was significantly altered by boat interactions. Dolphins spent less time foraging during interactions and took significantly longer to return to foraging once disrupted by vessel presence. This research raises concerns about the potential disruption to feeding, a biologically critical behaviour. This may be particularly important in an open oceanic habitat, where prey resources are typically widely dispersed and unpredictable in abundance. Furthermore, because tourism in this region focuses on common dolphins transiting between adjacent coastal locations, the potential for cumulative effects could exacerbate the local effects demonstrated in this study. While the overall level of compliance by commercial operators was relatively high, non-compliance to the regulations was observed with time restriction, number or speed of vessels interacting with dolphins not being respected. Additionally, prohibited swimming with calves did occur. The effects shown in this study should be carefully considered within conservation management plans, in order to reduce the risk of detrimental effects on common dolphins within the region.

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Restricted Boltzmann Machines (RBMs) are an important class of latent variable models for representing vector data. An under-explored area is multimode data, where each data point is a matrix or a tensor. Standard RBMs applying to such data would require vectorizing matrices and tensors, thus resulting in unnecessarily high dimensionality and at the same time, destroying the inherent higher-order interaction structures. This paper introduces Tensor-variate Restricted Boltzmann Machines (TvRBMs) which generalize RBMs to capture the multiplicative interaction between data modes and the latent variables. TvRBMs are highly compact in that the number of free parameters grows only linear with the number of modes. We demonstrate the capacity of TvRBMs on three real-world applications: handwritten digit classification, face recognition and EEG-based alcoholic diagnosis. The learnt features of the model are more discriminative than the rivals, resulting in better classification performance.