255 research outputs found
Validation of a Fault-Modeling Equipped Vapor Compression System Model Using a Fault Detection and Diagnostics Evaluation Tool
A methodology for evaluating the performance of fault detection and diagnostics (FDD) tools for unitary air-conditioners has been developed (Yuill and Braun 2013). The methodology uses laboratory measurements of systems with and without faults to test FDD tools’ effectiveness. A gray box modeling method capable of modeling systems with faults was developed by Cheung and Braun (2013a and 2013b) to provide input data, as an alternative to using laboratory data that had been collected. The simulation method was validated by direct comparison with experimental data, but a comparison of FDD evaluation results provides a more direct and useful validation of the model for its intended purpose. Eight different systems have been modeled using Cheung and Braun’s method. Six FDD tools were evaluated using both experimental and modeled inputs under the same environmental and fault conditions. The fault conditions include non-standard charging, heat exchanger fouling, loss of compressor volumetric efficiency, liquid line restriction, and the presence of non-condensable gas in the refrigerant. The model’s performance is characterized by comparing its outputs from the evaluation – false alarm rates, misdiagnosis rates, missed detection rates, and rates of undiagnosed faults – with the results based upon experimental data. The model is found to be highly suitable for its purpose
Evaluating Fault Detection and Diagnostics Tools with Simulations of Multiple Vapor Compression Systems
A methodology for evaluating the performance of fault detection and diagnostics (FDD) tools applied to unitary air conditioners has been developed by Yuill and Braun (2013). Data from faulted and unfaulted systems operating over a range of driving conditions are fed to the FDD tools, and the FDD responses are compared to the known operating conditions. The methodology originally relied upon experimental measurement data, but the amount of available data is limited, and evaluations can be far more meaningful if the operating conditions of the inputs can be controlled. Furthermore, a finite input set can be learned by an FDD algorithm, and the evaluation can be thereby gamed. To solve these problems, a large library of data from multiple systems under a wide range of conditions, with and without faults of varying magnitude, was generated with simulations from a novel gray-box modeling approach (Cheung and Braun 2013a, 2013b). The simulation outputs are used to train a neural network model, which is coupled to software that executes the evaluation method. The neural network model is much simpler than the semi-empirical approach, so it can produce evaluation inputs very quickly. This facilitates the evaluator generating semi-random conditions to provide a unique set of evaluation data that are sufficiently accurate and numerous to provide repeatable results. Some evaluation results from several FDD protocols are used to illustrate the success of this approach
EU Cohesion policy 2007-13 and the implications for Spain : who gets what, when and how?
The recent negotiation of the EU budget and the associated reform of EU Cohesion policy have had major policy implications for Spain, the country in receipt of most Cohesion policy support in the current programming period (2000-06). EU enlargement, combined with relatively rapid growth in Spain, impacted on the eligibility of Spanish regions for Cohesion support while also taking the country as a whole beyond the eligibility threshold for the Cohesion Fund. As a result, based on the original Commission budget proposals of February 2004, Spain was facing a reduced Cohesion policy budget of at least a half (to below €30 billion). This paper first reviews the budget negotiations from a Spanish (Cohesion policy) perspective, identifying the key negotiating goals and the extent to which they were achieved. It then looks at the outcome of the negotiations for Spain, initially at the national level and then in the regions. It highlights the significant differential impacts of the cutbacks in Cohesion policy allocations at the regional level and the pressures on the Spanish government to modulate the regional impact of the budgetary changes. Having considered the direct funding implications of the new Cohesion policy, the second half of the paper is concerned with the regulatory, institutional and economic impacts of the new policy regime. Many of the reform proposals fit with Spanish priorities, not least the new rationale for Cohesion policy (with its stress on the Lisbon and Gothenburg agendas) and the new policy architecture (with all regions eligible for some form of support and with a related shift from a geographic to more of a thematic focus). The retention of the key Structural Funds principles has also been welcomed in Spain, unsurprising given the wealth of experience and expertise built up over three (high-spending) programming cycles. As in most Member States, the main regulatory concern relates to the extent to which a more simplified and devolved approach to Funds' implementation will be achieved in practice. As regards policy and institutional impacts, the paper brings together regional views on the new budgetary and regulatory frameworks and reviews how the new regulations are being implemented in practice. A discussion of the developing National Strategic Reference Framework and the related Operational Programmes makes clear that the strong emphasis on the Lisbon agenda is not viewed as a constraint in Spain; rather, it is felt to fit well with recent Spanish developments and goals. Finally, the paper considers the economic implications of the reductions in Cohesion policy support. On the basis of evaluation studies, it highlights the positive impact the Funds have had in the past and the potentially quite varied regional impacts the reductions in funding may have in the future
Contesting the Dominant Discourse of Child Sexual Abuse: Sexual Subjects, Agency, and Ethics
Responding to previous scholars’ call to explore the complexities of child sexual abuse (CSA), this article presents narratives of CSA and scrutinizes a binary construction underpinning this discourse of CSA, namely, the positioning of children as powerless and adults as powerful. The narratives belong to three Indonesian young people who have had sexual interactions with adults when they were children. The findings demonstrate how this binary positioning has been both drawn upon and resisted in the ways participants understand their sexual experiences. This article contributes to the existing literature by providing analyses of some vignettes of everyday experiences of how children might be constituted as sexual subjects, including their capability to exercise agency, perform resistance, and negotiate ethics. The implications of the findings are discussed in relation to how the recognition of children as sexual subjects and their sexual agency might be beneficial for parents, educators, and counselors
PDD symptoms in ADHD, an independent familial trait?
The aims of this study were to investigate whether subtle PDD symptoms in the context of ADHD are transmitted in families independent of ADHD, and whether PDD symptom familiality is influenced by gender and age. The sample consisted of 256 sibling pairs with at least one child with ADHD and 147 healthy controls, aged 5-19 years. Children who fulfilled criteria for autistic disorder were excluded. The Children's Social Behavior Questionnaire (CSBQ) was used to assess PDD symptoms. Probands, siblings, and controls were compared using analyses of variance. Sibling correlations were calculated for CSBQ scores after controlling for IQ, ADHD, and comorbid anxiety. In addition, we calculated cross-sibling cross-trait correlations. Both children with ADHD and their siblings had higher PDD levels than healthy controls. The sibling correlation was 0.28 for the CSBQ total scale, with the CSBQ stereotyped behavior subscale showing the strongest sibling correlation (r = 0.35). Sibling correlations remained similar in strength after controlling for IQ and ADHD, and were not confounded by comorbid anxiety. Sibling correlations were higher in female than in male probands. The social subscale showed stronger sibling correlations in elder than in younger sibling pairs. Cross-sibling cross-trait correlations for PDD and ADHD were weak and not-significant. The results confirm that children with ADHD have high levels of PDD symptoms, and further suggest that the familiality of subtle PDD symptoms in the context of ADHD is largely independent from ADHD familiality
Gating of a pH-Sensitive K2P Potassium Channel by an Electrostatic Effect of Basic Sensor Residues on the Selectivity Filter
K+ channels share common selectivity characteristics but exhibit a wide diversity in how they are gated open. Leak K2P K+ channels TASK-2, TALK-1 and TALK-2 are gated open by extracellular alkalinization. The mechanism for this alkalinization-dependent gating has been proposed to be the neutralization of the side chain of a single arginine (lysine in TALK-2) residue near the pore of TASK-2, which occurs with the unusual pKa of 8.0. We now corroborate this hypothesis by transplanting the TASK-2 extracellular pH (pHo) sensor in the background of a pHo-insensitive TASK-3 channel, which leads to the restitution of pHo-gating. Using a concatenated channel approach, we also demonstrate that for TASK-2 to open, pHo sensors must be neutralized in each of the two subunits forming these dimeric channels with no apparent cross-talk between the sensors. These results are consistent with adaptive biasing force analysis of K+ permeation using a model selectivity filter in wild-type and mutated channels. The underlying free-energy profiles confirm that either a doubly or a singly charged pHo sensor is sufficient to abolish ion flow. Atomic detail of the associated mechanism reveals that, rather than a collapse of the pore, as proposed for other K2P channels gated at the selectivity filter, an increased height of the energetic barriers for ion translocation accounts for channel blockade at acid pHo. Our data, therefore, strongly suggest that a cycle of protonation/deprotonation of pHo-sensing arginine 224 side chain gates the TASK-2 channel by electrostatically tuning the conformational stability of its selectivity filter
Students’ Perceptions of Learning Processes as Co-Authors of Digital Tabletop Activities
We conducted a small-scale study in order to explore students’ perceptions of the learning processes when engaged as co-authors of content for collaborative higher order thinking skills learning tasks. We specifically designed the process to allow for self-critique – where authors can observe their creations being solved and therefore understand where they may improve their design. We collected data over a three-day period from a sample of twelve thirteen year olds, working in teams, authoring content for Digital Mysteries (a higher order thinking skills collaborative learning application based on the digital tabletop). The study was structured to follow Bloom’s taxonomy, a continuum of cognitive skills that develop during a learning process. We found that 1) rather than follow this continuum, skills developed in a non-linear manner due to the abstract nature of the authoring activity, and 2) the students’ demonstrated good metacognitive insights into the authoring task, technology and collaborative learning as a whole
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Working memory, reading ability and the effects of distance and typicality on anaphor resolution in children
We investigated the time course of anaphor resolution in children and whether this is modulated by individual differences in working memory and reading skill. The eye movements of 30 children (10?11 years) were monitored as they read short paragraphs in which (1) the semantic typicality of an antecedent and (2) its distance in relation to an anaphor were orthogonally manipulated. Children showed effects of distance and typicality on the anaphor itself and also on the word to the right of the anaphor, suggesting that anaphoric processing begins immediately but continues after the eyes have left the anaphor. Furthermore, children showed no evidence of resolving anaphors in the most difficult condition (distant atypical antecedent), suggesting that anaphoric processing that is demanding may not occur online in children of this age. Finally, working memory capacity and reading comprehension skill affect the magnitude and time course of typicality and distance effects during anaphoric processing
Children’s Moral Emotion Attribution in the Happy Victimizer Task: The Role of Response Format
Previous research in the happy victimizer tradition indicated that preschool and early elementary-school children attribute positive emotions to the violator of a moral norm, whereas older children attribute negative moral emotions. Cognitive and motivational processes have been suggested as underlying this developmental shift. The current research investigated whether making the happy victimizer task less cognitively demanding, by providing children with alternative response formats, would increase children’s attribution of moral emotions and moral motivation. In Study 1, 93 4- to 7-year-old British children responded to the happy victimizer questions either in a normal condition (where they spontaneously pointed with a finger), a wait condition (where they had to wait before giving their answers), or an arrow condition (where they had to point with a paper arrow). In Study 2, 40 Spanish 4-year-old children responded in the happy victimizer task either in a normal or a wait condition. In both studies, participants’ attribution of moral emotions and moral motivation was significantly higher in the conditions with alternative response formats (wait, arrow) than in the normal condition. The role of cognitive abilities for emotion attribution in the happy victimizer task is discussed
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