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Changes in School Results in EQAO Assessments from 2006 to 2010Ram, Anita 19 December 2012 (has links)
Many accountability systems use data from large-scale assessments to make judgements about school performance. In Ontario, school performance is often assessed using the percentage of proficient students (PPS). The purpose of this study was to shed light on the degree and frequency of changes from year to year in the percentage of proficient students, at a school, in the areas of reading, writing and mathematics for both grades 3 and 6 in Ontario from 2006 to 2010. A second purpose was to assess the influence of cohort size on the variability in scores from year to year. Once schools not having data for 5 consecutive years and outliers were omitted secondary data analysis was used to examine nearly 3000 schools in each subject and grade. For the first part of the study, descriptive statistics and frequencies were the main method of examination. In the second part of the study, variance scores and correlations were used in order to understand the relationship between changes in PPS and cohort size. Findings revealed that changes in school scores from year to year are very large for many schools. Approximately 50 percent of schools experienced changes in PPS greater than 10 percent in any given year. When examining how often, from 2006 to 2010, a school experienced a similar amount of change – generally, both the smallest and largest change categories had a larger percentage of schools experiencing a similar amount of change for two and three years. Very seldom did schools experience the same degree of change in PPS across all 5 years. Results from correlations revealed a significant and inverse relationship between average cohort size and variability in PPS. Considering over 80 percent of schools have 60 or fewer students in a cohort the unpredictability in PPS may prove to be quite frustrating to schools and confusing to stakeholders. Annual PPS scores appear to be a poor indicator of real school performance, and their use to rank or rate schools should be avoided. Recommendations are made about using PPS to report school level results for EQAO, schools and the public.
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Changes in School Results in EQAO Assessments from 2006 to 2010Ram, Anita 19 December 2012 (has links)
Many accountability systems use data from large-scale assessments to make judgements about school performance. In Ontario, school performance is often assessed using the percentage of proficient students (PPS). The purpose of this study was to shed light on the degree and frequency of changes from year to year in the percentage of proficient students, at a school, in the areas of reading, writing and mathematics for both grades 3 and 6 in Ontario from 2006 to 2010. A second purpose was to assess the influence of cohort size on the variability in scores from year to year. Once schools not having data for 5 consecutive years and outliers were omitted secondary data analysis was used to examine nearly 3000 schools in each subject and grade. For the first part of the study, descriptive statistics and frequencies were the main method of examination. In the second part of the study, variance scores and correlations were used in order to understand the relationship between changes in PPS and cohort size. Findings revealed that changes in school scores from year to year are very large for many schools. Approximately 50 percent of schools experienced changes in PPS greater than 10 percent in any given year. When examining how often, from 2006 to 2010, a school experienced a similar amount of change – generally, both the smallest and largest change categories had a larger percentage of schools experiencing a similar amount of change for two and three years. Very seldom did schools experience the same degree of change in PPS across all 5 years. Results from correlations revealed a significant and inverse relationship between average cohort size and variability in PPS. Considering over 80 percent of schools have 60 or fewer students in a cohort the unpredictability in PPS may prove to be quite frustrating to schools and confusing to stakeholders. Annual PPS scores appear to be a poor indicator of real school performance, and their use to rank or rate schools should be avoided. Recommendations are made about using PPS to report school level results for EQAO, schools and the public.
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Physical Security System Sensitivity to DBT PerturbationsConchewski, Curtis 2012 August 1900 (has links)
This thesis examines how perturbing selected adversary capabilities in a design basis threat (DBT) may affect the assessment of a facility's security system performance. We found that using a strictly defined DBT to design and analytically test facility security systems can lead to invalid assessments that security measures are meeting standards. Design Basis Threats are intended to represent the most severe yet realistic attack a facility might face. However, the static nature of the standard DBT makes it unable to test the performance of a facility security system in the case where a specialized adversary may possess different capabilities than defined in the DBT. Our analysis of security system performance for various modeled facilities revealed significant vulnerabilities to certain perturbations of adversary capabilities. These vulnerabilities went undetected when the original strictly defined graded DBT was used in the assessment procedure. By maximizing one adversary capability at the expense of others, a specialized adversary force was able to efficiently defeat each facility.
To address this problem, we proposed employing a so-called "point-based" DBT as an alternative to the existing strictly defined DBT. In a point-based DBT, multiple scenarios are assessed that test different sets of adversary capabilities to better uncover and understand any security system vulnerabilities that may exist. We believe the benefit of identifying these site-specific security vulnerabilities will outweigh the additional cost of generating a point-based DBT, especially if the vulnerabilities are identified during the initial design of the security system.
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Engaging with persistent medically unexplained physical symptoms in healthcare : a realist psychosexual service evaluationPenman, Jean January 2015 (has links)
In this study the phenomenon of persistent physical symptoms (PPS) has been examined by realist evaluation of research and practice. Nimnuan et al., (2001) have shown that up to 35% of patients in primary care and 66% in specialist out-patient clinics have presented with such ‘medically unexplained’ symptoms. The cost in medical investigation to reach diagnosis for PPS is an estimated 10% of the annual UK National Health Service budget (Bermingham et al., 2010) but poor patient outcomes prevail (Dwamena et al., 2009). Currently, PPS is linked to high comorbidity with anxiety and depression (DH 2011b) and Cognitive Behavioural Therapy (CBT) is advised as the evidence based treatment for PPS (IAPT, 2014). However, a shortfall in clinical skills to address PPS is also demonstrated and engagement could be improved (De Lusignan et al., 2014). Moreover, the pragmatic study of alternative therapy modalities and processes for PPS is recommended (Leichsenring, 2005). To obtain a broader knowledge of process for patients with or without co-morbidity, practice based experience suggests that one such alternative is a brief psychodynamic intervention (STPP) for PPS. A Realist Literature Synthesis (Wong et al. 2013) highlights effective psychotherapeutic STPP interventions in real world circumstances in 5 comparison with CBT interventions for heterogenous PPS. STPP for PPS is found at least as effective as CBT, with improved engagement rates. Additionally, common factors were discovered between ‘third generation’ STPP and CBT for effective PPS interventions and these were developed into a preliminary cross-modality theoretical analytical framework. In the realist contextual evaluation (Pawson and Tilley, 1997) of a psychosexual service delivery, the majority of PPS sufferers were found only moderately co-morbid with anxiety and depression. For complete investigative study, clinical tools are developed providing integrative CBT/STPP principles for engagement with PPS for teaching, training and practice. In conclusion, the findings suggest that the reflexive insider position of the realist Therapist-Evaluator facilitates systematically derived Practice-Based Evidence of PPS process, meeting recommendations of Deary et al., (2007) to explore and define process and outcomes with PPS. The findings contribute to development of a conceptual platform to support health professionals in overcoming physical/mental health barriers to addressing PPS and wider patient access to effective care (NHSE, 2014, 2015).
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Friction spot joining of aluminum alloy 2024-t3 and carbon-fiber-reinforced polyphenylene sulfide composite laminate with additional pps film interlayerAndré, Natália Manente 30 November 2015 (has links)
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Previous issue date: 2015-11-30 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Friction Spot Joining (FSpJ) is a prize-winning joining technique for hybrid
metal-polymer composite structures. This master thesis was devised to
investigate the feasibility of FSpJ of metal-composite structures with additional
film interlayer. Friction spot joints of aluminum alloy 2024-T3 and carbon-fiberreinforced
polyphenylene sulfide laminate composite with additional PPS film
interlayer were successfully produced. The highest peak temperature achieved
during the joining process was 417°C. DSC analysis demonstrated that the
degree of crystallinity decreased for the composite (from 22% to 12%) and
increased for the PPS film (from 7% to 27%) after joining. TGA analysis
indicated that no extensive thermo-mechanical degradation induced by the
joining process occurred. The main bonding mechanisms of FSp joint were
identified as macro- and micro-mechanical interlocking, as well as adhesion
forces. The process-related microstructural effects were evaluated and
correlated to the local mechanical performance of the joining parts through
micro and nanohardness. Further, mechanical grinding, sandblasting and
plasma activation surface pre-treatments were performed on the composite part
to enhance the adhesion between the joining parts. The generated surface
features due to the surface pre-treatments were correlated to the mechanical
performance of the joints. Sandblasted specimens showed the best mechanical
performance among the surface pre-treatments used in this work. The lap shear
strength of joints with interlayer (2703 ± 114 N up to 3069 ± 166 N) was up to
55% higher than the corresponding joints without film. The fatigue life of the
joints with interlayer was 4 times longer in comparison with those without
interlayer; superior fatigue strength was also observed. The durability of the
joints was evaluated through hydrothermal accelerated aging; the maximum
reduction in initial strength was 12.4% for 28 days of aging. Finally, the failure
mechanisms of the joints were discussed, demonstrating a mixture of adhesivecohesive
failure mode. / A União Pontual por Fricção (FSpJ) é uma técnica internacionalmente
premiada para união de estruturas híbridas metal-compósito polimérico. Esta
dissertação de mestrado investigou a viabilidade técnica da produção de juntas
metal-compósito com filme polimérico intermediário através do FSpJ. Juntas de
alumínio 2024-T3 e laminado compósito de poli(sulfeto de fenileno) (PPS)
reforçado com fibras de carbono com filme intermediário de PPS foram
produzidas com sucesso. A máxima temperatura processual identificada foi de
417°C. Análises de DSC demonstraram decréscimo no grau de cristalinidade
do compósito (de 22% para 12%) e acréscimo no caso do filme intermediário
(de 7% para 27%) depois de submetidos ao processo de união. Análises de
TGA não identificaram evidências de ocorrência de degradação termomecânica
dos componentes poliméricos das juntas induzida pelo FSpJ. Os principais
mecanismos de união identificados na interface das juntas foram macro- e
micro-ancoramento mecânico, além de forças adesivas. As mudanças
microestruturais induzidas pelo processo de união foram investigadas e
correlacionadas com o desempenho mecânico local dos componentes da junta
através de medidas de micro e nanodureza. Pré-tratamentos superficiais de
lixamento, jateamento de areia e ativação por plasma foram realizados no
componente compósito a fim de aprimorar a adesão entre os componentes a
serem unidos. As superfícies pré-tratadas foram caracterizadas e suas
propriedades foram correlacionadas com a resistência mecânica das juntas
correspondentes. As amostras jateadas produziram juntas com a melhor
resistência mecânica entre os pré-tratamentos superficiais investigados neste
estudo. A resistência ao cisalhamento das juntas com filme (2703 ± 114 N até
3069 ± 166 N) apresentou-se até 55% superior à resistência das respectivas
juntas sem filme. A vida em fadiga das juntas com filme apresentou-se cerca de
4 vezes mais longa em comparação às juntas sem filme. A durabilidade das
juntas foi investigada através de envelhecimento hidrotérmico acelerado, sendo
que a máxima redução em resistência ao cisalhamento foi de 12,4% para 28
dias de envelhecimento. Finalmente, os mecanismos de falha das juntas foram
discutidos, demonstrando a predominância do modo coesivo de falha.
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Etude comparative du comportement composites à matrice thermoplastique ou thermodurcissable / Comparative study of the behavior of thermoplastic or thermoset matrix comositesAucher, Jérémie 08 December 2009 (has links)
Cette thèse consiste en une étude comparative des propriétés thermomécaniques de composites tissés à matrice thermoplastique (PEEK ou PPS) et thermodurcissable (époxy). Une analyse bibliographique a permis la comparaison les comportements des ces stratifies en fonction de la nature de la matrice, de la sollicitation et des conditions environnementales. Une étude expérimentale a conduit à une base de données des trois matériaux sous diverses sollicitations mécaniques (essais monotones élémentaires et structures) et différentes conditions environnementales (température et V.H.). Des essais sur assemblages boulonnes (simple et double recouvrement) ont également été réalisés. Une technique de mesure de champ par corrélation d’images numériques a permis d'étudier le comportement de stratifies troues. Enfin, un modèle de comportement élastoplastique orthotrope de stratifies tisses a matrice thermoplastique a été implémenté dans le code E.F. cast3m et valide pour différentes températures. / This PhD thesis consists in a comparative study of the thermomechanical properties of woven plies composites with a thermoplastic (PEEK or PPS) or a thermosetting (epoxy) matrix. A literature review allowed the comparison between the behaviors of these laminates depending on the matrix nature, the stress state and the environmental conditions. An experimental study led to a database of the three materials for different mechanical loads (monotonic and structural tests) under specific environmental conditions (temperature and wet ageing). Bolted joints tests (single bolt single lap and double lap) have also been performed. A digital pictures correlation technique permitted to study the behavior of circular notched laminates. At last, a model of orthotropic elastoplastic behavior for woven plies laminates with a thermoplastic matrix has been implemented in the F.E. code cast3m and has been validated for different temperatures.
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Analyse und Neuimplementierung eines agentenbasierten FertigungsmanagementsystemsGelbke, Stefan 10 December 2006 (has links)
Heutige Systeme für die Fertigungssteuerung müssen viele unterschiedliche Problemstellungen lösen. Vor allem die Komplexität der Anforderungen sowie die unterschiedlichen Interessen am Ablaufplan, wie hohe Termintreue, kurze Durchlaufzeiten und geringe Produktionskosten, gilt es zu beachten. Erschwert wird dies durch kurze Planungsfristen und hohe Flexibilitätsanforderungen. Komplexe Problemstellungen werden in der künstlichen Intelligenz unter anderem durch den Einsatz von Multiagentensystemen gelöst. Ein solches System zeichnet sich durch eine hohe Flexibilität sowie schnelle Reaktion auch auf unbekannte und nicht spezifizierte Ereignisse aus.
Im Rahmen dieser Arbeit werden beide Forschungsgebiete miteinander verknüpft und so der Ansatz des agentenbasierten Fertigungsmanagements verfolgt. Der Schwerpunkt wird dabei auf die Ablaufplanung mit Anwendung auf produzierende Unternehmen gelegt. Vorgestellt wird ein Konzept, das auf Basis der Multiagenten-Technologie neue Aufträge möglichst schnell einplant und das eine Reparatur zur Herstellung der Konsistenz des Planes binnen Sekunden durchführt. Weiterhin findet die Vorstellung einer Planoptimierung statt, welche die vom Bediener spezifizierten Optimalitätsbedingungen umsetzt. Alle diese Verfahren laufen dezentral durch die Agenten ab und werden nur grob durch einen speziellen Agenten gesteuert. Grundlage des Systems ist ein Bewertungssystem, das den Plan anhand verschiedener Kriterien beurteilt.
Zur Überprüfung der Funktion des erarbeiteten Konzeptes wurde ein Prototyp implementiert und anschließend analysiert. Trotz der Anwendung auf die Fertigungssteuerung sind alle Ansätze allgemein gehalten und können somit auch auf andere Bereiche, in denen eine Planung erforderlich ist, angewendet werden.
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The Effects of the Type of Skill Assessment on the Motivation of Students in Physical EducationJohnson, Tyler Gene 27 July 2004 (has links) (PDF)
The purposes of this study were to (1) examine the effects of criterion-referenced (i.e., Programmed Practice Sheet or PPS) and norm-referenced (i.e., standardized) skill assessments on the situational motivation of junior high school physical education students (N = 507), (2) determine if student task and ego dispositions could be affected by the type of skill assessment administered, and (3) determine if having choices of skill level affects student situational motivation and perception of autonomy support. Student situational motivation, task and ego disposition, and sense of autonomy were assessed using the Situational Motivation Scale (SIMS), Perception of Success Questionnaire (POSQ), and the Self-Regulation Questionnaire-Autonomy (SRQ-A). Results revealed significant differences between the criterion-referenced/choice Group 4 and the norm-referenced/no choice Group 1 as follows: Group 4 (a) had a greater sense of identified regulation, (b) had a lesser sense of external control, and (c) was less amotivated than Group 1. Significant gender by group interactions were found, thus indicating that girls were more affected by test type than boys. Girls in Group 4 (a) felt a lesser sense of external regulation, (b) had a greater sense of identified regulation, and (c) were more intrinsically motivated than girls in Group 1. Also, girls in Group 4 (a) felt a greater sense of identified regulation and (b) were more intrinsically motivated than girls in the norm-referenced/choice Group 2. These findings provide some evidence that using criterion-referenced skill assessments, like the PPS, and offering choices of skill level may enhance student situational motivation during skill assessment. No significant differences were found in student task and ego disposition and perception of autonomy support.
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Characterization of pps, a Modulator of Sxl Autoregulation in Drosophila melanogasterJohnson, Matthew Logan January 2010 (has links)
No description available.
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Material Characterization and Life Prediction of a Carbon Fiber/Thermoplastic Matrix Composite for Use in Non-Bonded Flexible RisersRussell, Blair Edward 05 January 2001 (has links)
In the effort to improve oil production riser performance, new materials are being studied. In the present case, a Polymer Matrix Composite (PMC) is being considered as a replacement for carbon steel in flexible risers manufactured by Wellstream Inc., Panama City, Florida. The Materials Response Group (MRG) at Virginia Tech had the primary responsibility to develop the models for long-term behavior, especially remaining strength and life. The MRG is also responsible for the characterization of the material system with a focus on the effects of time, temperature, and environmental exposure. The present work is part of this effort. The motivation to use a composite material in a non-bonded flexible riser for use in the offshore oil industry is put forth. The requirements for such a material are detailed. Strength analysis and modeling methods are presented with experimental data. The effect of matrix crystallinity on composite mechanical properties is shown. A new method for investigating matrix behavior at elevated temperatures developed. A remaining strength life prediction methodology is recalled and applied to the case of combined fatigue and rupture loading. / Master of Science
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