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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Indirect Measures as Predictors of Social Skills Observed through Means of Direct Observation

Sidwell, MacKenzie Denise 11 August 2017 (has links)
The scope of the current study focuses on the relationship between direct and indirect methods of measuring social skills in children. Participants included 33 children between the ages of 6 and 11 years old. The sample drew from elementary schools in 2 Southern states in the U.S., as well as social skills groups from a university-based clinic. While some participants had been previously identified has having disabilities impacting social performance, it was not an inclusionary requirement and the majority of children were not identified as having a disability clinically or through a special education eligibility domain. Teachers and clinicians leading social skills groups completed indirect measures, the Behavior Assessment Scale for Children Third Edition (BASC-3) and the Social Skills Improvement System (SSIS) related to the participants’ social skills. Direct observations of participants were completed using the Social Observation System (SOS) by graduate level research assistants. Hierarchical multiple regression analyses were conducted to determine the predictive value of the teacher informed indirect measures on the direct method of observation. Additionally, simple linear regression analyses were conducted to examine the reverse relationship of the direct observation’s ability to predict the variance observed in each indirect measure. Results indicated that both the indirect and direct methods of social skills assessment can significantly predict the other. However, while significant, a low to moderate amount of variance in the direct measure is explained by the indirect measures of social skills. The results and implications of the finding are discussed, as well as limitations and future directions.
2

Direct measurement of the top-quark decay width with the ATLAS detector

Dado, Tomas 12 June 2019 (has links)
No description available.
3

Magnetokalorický jev sloučenin vzácných zemin / Magnetocaloric properties of rare-earth compounds

Kaštil, Jiří January 2014 (has links)
This work presents study of magnetocaloric properties of compounds exhibiting unusual magnetic characteristics. Several systems were studied: TbNiAl, (Tb,Y)NiAl, TbNi(Al,In), TbFeAl, GdFeAl, Ni2MnGa based compounds and amorphous metallic alloy Gd-Co-Al-Y. Influence of magneto-crystalline anisotropy on magnetocaloric effect was studied on singlecrystalline sample of TbNiAl compound. The maximum of entropy change was measured with orientation of magnetic field along c axis and compared to polycrystalline sample a 100% increase was observed. Substitutions of Y and In in TbNiAl led to a change of magnetic ordering. Both substitution led to increase of RCP values of studied material. TbFeAl and GdFeAl compounds, characterized by partial disorder of Fe and Al atoms, showed magnetocaloric effect in wide temperature region which led to interesting values of RCP~350 J kg-1 . Very broad region of magnetocaloric effect was also observed on amorphous metallic material of Gd-Co-Al-Y. The effect of Er substitution in Ni2MnGa based compound on its magneto-structural transition, connected with inverse magnetocaloric effect, was studied. The direct measurement method of adiabatic temperature change is described and instrument for such measurement, developed in collaboration with FZU AVČR, v.v.i., is presented.
4

Hurricane Katrina, Citizen Displacement, and Social Control: A Test of the Threat and Benign Neglect Hypotheses and an Investigation of the Crime-Arrest Relationship

Myer, Andrew James 06 December 2010 (has links)
No description available.
5

Kalibrace závaží a vah / Calibration of weights and balances

Vojtová, Klára January 2013 (has links)
In the introductory chapter of this work is caught organizational structure of the national metrology system in the Czech Republic and its links to international organizations. There is indicated the basic terminology of metrology, particularly in the area of classification instruments. The following sections approaching the issue of measurement uncertainties, their classification, sources of uncertainty determined by the type A and B, their specifics and calculation. The above linked area already dealing with themselves calibrations, first of all calibration weights, classification of weights according accuracy classes, established procedures, and finally determining uncertainty in calibration weights. Then, immediately followed by a chapter dealing with calibration balances, performed tests and measurement uncertainties. The main part is of course directed towards the application of acquired knowledge to practical examples, thus performing the calibration weight class F2 using a high-precision weights, both in the premises of the Technical University in Brno, both in the laboratory weighing the Czech Metrological Institute. Further calibration was performed school balances Ohaus Explorer EX224.
6

Improving Objectivity and Reliability of Observational Risk Assessment Tools by using Technical Instruments / Observationsmetoder för ergonomisk riskbedömning – ökad objektivitet och tillförlitlighet med hjälp av tekniska mätningar

Charsmar-Etor, Cephas January 2023 (has links)
Ergonomic assessments to determine risks of work-related musculoskeletal disorders as well as to compare designs of work-tasks and workstations, are imperative for high sustainability and productivity in any given industry. Hence, assessment tools that can objectively and reliably capture postures, joint angles and muscle activities play very important role in properly determining risks relating to work and various tasks. The introduction of direct measurement instruments/tools has been helping and continue to help improve upon observational assessment methods to attain objectivity and reliability. This project aimed at contributing to future improvements of industrial risk assessment measures in ergonomics by identifying and testing direct measurement instruments/tools that can enhance observational risk assessment methods and introduce a new way of signal processing, hence, reducing assessment time while increasing objectivity and reliability. Several candidate instruments were identified and out of the identified, ten were selected as potential candidates. Two out of the ten, Wergonic and ErgoHandMeter were then selected and tested on common observation risk assessment factors that could be measured and answers provided directly or by analyses. The Wergonic instrument was modified to enhance its measuring capability from one fully and partially two factors to six factors. New algorithms were also employed to analyse measurements of the ErgoHandMeter in order to answer questions regarding repetitive movements. The two instruments tested, are able to measure and provide results for six commonly and one rarely assessed biomechanical risk factors. By combining selected potential candidates, many of the commonly targeted biomechanical risk factors in observational instruments can be measured by the selected direct measurement instruments. However, some factors especially force measurement remain a challenge for measuring by direct wearable sensor instruments.
7

Contribution à la détermination de la courbe de pression de vapeur saturante de l’eau pure dans la plage de –80 °C à +100 °C, avec une très haute exactitude / Contribution to the determination of the vapour pressure curve of pure water in the temperature range between -80 ° C to +100 ° C, with high accuracy

Mokdad, Sid-Ali 28 September 2012 (has links)
La détermination des propriétés physiques de l’eau pure, notamment la pression de vapeur saturante en fonction de la température, est un enjeu majeur en humidité et identifié comme tel par le Comité Consultatif de Thermométrie (CCT-WG6) sous-groupe Humidité du Comité Technique de Température (TC-T) afin d’améliorer les incertitudes des références nationales en humidité. A cette fin, le LNE-CETIAT et le LNE-Cnam ont développé conjointement un dispositif expérimental permettant d’accéder au couple température / pression de vapeur saturante de l’eau pure. Le principe est basé sur une mesure statique de la pression et de la température dans une cellule d’équilibre associée à un calorimètre quasi-adiabatique. La gamme de température d’équilibre couverte s’étend de 193,15 K à 373,15 K, correspondant à une pression de vapeur saturante allant de 0,06 Pa à 105 Pa.Ce travail présente la description, la réalisation et la caractérisation métrologique de ce nouveau dispositif expérimentale. Les résultats des mesures expérimentales sont comparés avec les travaux théoriques et expérimentaux les plus récents. Le budget d'incertitude finale prend en compte la contribution de la mesure de pression, de la mesure de température et des effets parasites telles que la transpiration thermique et la pression aérostatique. Grace aux différentes solutions mises en œuvre, la contribution des mesures de température dans le bilan d’incertitude globale est réduite. La part prépondérante reste essentiellement associée à la mesure de pression. / The determination of the physical properties of pure water, especially the vapor-pressure curve, is one of the major issues identified by the Consultative Committee for Thermometry (CCT) of the technical committee in thermometry sub-field hygrometry to improve the accuracy of the national references in humidity.In order to achieve this objective, the LNE-CETIAT and the LNE-Cnam have jointly built a facility dedicated to the measurement of the saturation vapor pressure and temperature of pure water. The principle is based on a static measurement of the pressure and the temperature of pure water in a closed, temperature-controlled thermostat, conceived like a quasi-adiabatic calorimeter. The explored temperature range lies between 193,15 K and 373,15 K, and the pressure range between 0,06 Pa and 105 Pa.This work presents a full description of this facility and the preliminary results obtained for its characterization. The obtained results have been compared with available literature data. The final uncertainty budget took into account several components: pressure measurements, temperature measurements and environmental error sources such as thermal transpiration and hydrostatic pressure correction. Thanks to the employment of several technical solutions, the thermal contribution to the overall uncertainty budget is reduced, and the remaining major part is mainly due to pressure measurements.
8

Zvyšování účinnosti třífázových asynchronních motorů / The improvement of efficiency of three-phase induction motors

Vinkler, Stanislav January 2014 (has links)
This work is dedicated to increasing the effectiveness of a particular draft induction motor, which was before the change and subjected to laboratory measurements according to EN60034 - 2-1, an analytical calculation of the losses and the overall efficiency and analysis program RMxprt. The first part focuses on the analysis of measurement data, measurement of partial loss in the machine and overall efficiency. In the second chapter, losses and efficiency calculated analytically, in the first case using the links in the professional literature dealing with the design of electric motors and in the second case by a program for the rapid design of rotating electrical machines, RMxprt program. At the end of this chapter all parameters are obtained measurements and calculations are compared. The third chapter is devoted to the calculation of losses and the resulting efficiency machines in a computer program, in which I gradually adopted changes to increase the efficiency of electrical machines. It also shows the calculation of the new dimensions of the stator and rotor slots. In the fourth chapter, the preparation of documentation for the production of a new two-layer winding for the current machine, while preserving the original dimensions of stator slots. The last part is devoted to the analysis of measurement data on the supplied asynchronous motor with a newly designed stator winding. In conclusion then discussed the results of work.
9

Análisis del uso de escalas de medida de influencia en el proceso analítico de redes (ANP) para la toma de decisiones multicriterio

Schulze González, Erik Alejandro 07 September 2023 (has links)
[ES] La toma de decisiones en situaciones complejas y dinámicas representa un gran desafío para los tomadores de decisiones, quienes deben considerar múltiples criterios interdependientes. En este contexto, los métodos de análisis multicriterio de decisión (MCDA) son ampliamente utilizados, pero la mayoría de ellos asumen que los criterios son independientes, lo cual no es aplicable en la mayoría de los problemas del mundo real. El proceso analítico en red (ANP) es una técnica de MCDA que permite modelar las interacciones entre los criterios de decisión, lo que la hace más aplicable a problemas reales. ANP es una generalización del método de proceso jerárquico analítico (AHP), pero a diferencia de este último, reconoce las influencias recíprocas entre los elementos en un problema de toma de decisiones. ANP utiliza una red ponderada y dirigida para modelar estas interacciones, lo que permite una modelización más realista y precisa del problema. Aunque ANP es el método preferido para modelar situaciones de interdependencia y retroalimentación, presenta desafíos en la práctica, particularmente debido al gran número de comparaciones por pares requeridas. Esta tesis aborda la complejidad de ANP y su principal desafío: las matrices de comparación por pares que miden la influencia de un elemento sobre otro en la red. Se presenta un modelo híbrido de ANP simplificado con la técnica DEMATEL que reduce el número de comparaciones por pares necesarias mediante la utilización de escalas de influencia directa, lo que lo hace más factible de aplicar en la práctica. Además, se han recomendado escalas de medición de influencia directa para normalizar los valores numéricos obtenidos, dividiendo por la suma en lugar de una matriz de transición. La medida se vuelve más precisa con más divisiones de escala. En el estudio de caso presentado, se demostró que la propuesta de modelo combinado DEMATEL basado en ANP puede reducir en promedio el 42% del número de preguntas necesarias en comparación con el modelo ANP original, y aun así obtener resultados similares. / [CA] La presa de decisions en situacions complexes i dinàmiques representa un gran desafiament per als prescriptors, els quals han de considerar múltiples criteris interdependents. En aquest context, els mètodes d'anàlisi multicriteri de decisió (MCDA) són àmpliament utilitzats, però la majoria d'ells assumeixen que els criteris són independents, la qual cosa no és aplicable en la majoria dels problemes del món real. El procés analític en xarxa (ANP) és una tècnica de MCDA que permet modelar les interaccions entre els criteris de decisió, la qual cosa la fa més aplicable a problemes reals. ANP és una generalització del mètode de procés jeràrquic analític (AHP), però a diferència d'aquest últim, reconeix les influències recíproques entre els elements en un problema de presa de decisions. ANP utilitza una xarxa ponderada i dirigida per modelar aquestes interaccions, la qual cosa permet una modelització més realista i precisa del problema. Encara que ANP és el mètode preferit per modelar situacions d'interdependència i retroalimentació, presenta desafiaments en la pràctica, particularment a causa del gran nombre de comparacions per parells requerides. Aquesta tesi aborda la complexitat d'ANP i el seu principal desafiament: les matrius de comparació per parells que mesuren la influència d'un element sobre un altre en la xarxa. Es presenta un model híbrid d'ANP simplificat amb la tècnica DEMATEL que redueix el nombre de comparacions per parells necessàries mitjançant l'utilització d'escales d'influència directa, la qual cosa el fa més factible d'aplicar en la pràctica. A més, s'han recomanat escales de mesura d'influència directa per normalitzar els valors numèrics obtinguts, dividint per la suma en lloc d'una matriu de transició. La mesura es torna més precisa amb més divisions d'escala. En l'estudi de cas presentat, es va demostrar que la proposta de model combinat DEMATEL basat en ANP pot reduir en promig el 42% del nombre de preguntes necessàries en comparació amb el model ANP original, i encara obtenir resultats similars. / [EN] Decision-making in complex and dynamic situations poses a great challenge for decision makers who must consider multiple interdependent criteria. In this context, multicriteria decision analysis (MCDA) methods are widely used, but most of them assume that criteria are independent, which is not applicable in most real-world problems. Analytic network process (ANP) is an MCDA technique that allows modeling the interactions between decision criteria, making it more applicable to real-world problems. ANP is a generalization of the analytic hierarchy process (AHP), but unlike the latter, it recognizes reciprocal influences between elements in a decision-making problem. ANP uses a weighted and directed network to model these interactions, allowing for a more realistic and accurate modeling of the problem. Although ANP is the preferred method for modeling interdependence and feedback situations, it presents challenges in practice, particularly due to the large number of pairwise comparisons required. This thesis addresses the complexity of ANP and its main challenge: the pairwise comparison matrices that measure the influence of one element on another in the network. A simplified hybrid ANP model with the DEMATEL technique is presented, which reduces the number of pairwise comparisons required by using direct influence scales, making it more feasible to apply in practice. Additionally, recommended direct influence measurement scales have been suggested to normalize the numerical values obtained by dividing by the sum instead of a transition matrix. The measure becomes more precise with more scale divisions. In the case study presented, it was demonstrated that the proposed DEMATEL-ANP combined model can reduce on average 42% of the necessary questions compared to the original ANP model, and still obtain similar results. / Schulze González, EA. (2023). Análisis del uso de escalas de medida de influencia en el proceso analítico de redes (ANP) para la toma de decisiones multicriterio [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/196689
10

Shared representation of work-related musculoskeletal risk factors and comparison of assessment methods : an experimental study in the truck manufacturing industry / Représentation partagée des facteurs de risque des troubles musculosquelettiques et comparaison des méthodes d'évaluation : une étude expérimentale dans le secteur de l’assemblage de camions

Zare Mahmoudabadi, Mohsen 11 December 2015 (has links)
Les facteurs de risque de troubles musculo-squelettiques(TMS) tels que les facteurs physiques, organisationnels et psychosociaux sont un défi commun pour les industries de l'assemblage automobile qui entrainent des effets indésirables sur le système et les humains. L’ergonomie a déjà été intégrée dans les systèmes de production de ces industries pour la prise en charge de la prévention des TMS. La question est de savoir si l'approche ergonomique actuelle des industries automobiles, sur la base de normes à l'entreprise et des méthodes d'observation, peut fournir une connaissance partagée des facteurs ergonomiques pour les divers intervenants et pour faciliter l'amélioration des conditions de travail. Cette étude aborde la problématique du positionnement des différents méthodes d'évaluation (utilisées par les différents intervenants) et compare les résultats et apports de chaque méthode d'évaluation. Cette thèse propose que la procédure actuelle d'évaluation des risques de TMS ne favorise pas une connaissance partagée entre les intervenants dans les industries automobiles. On constate que les évaluations par auto-questionnaire (opérateurs) sont significativement différentes de celles issues des méthodes d'observation (ergonome) et des mesures directes (analyse biomécanique). Cependant, les opinions et jugements des opérateurs concernant les facteurs ergonomiques sont importants pour faciliter la réussite d'une approche ergonomique. Un entretien structuré et systématisé, basé sur des données objectives (Video-observations ou de mesure directe) liées aux activités et stratégies des opérateurs, pourrait être une procédure appropriée pour faire progresser l'ergonomie des situations de travail. Enfin, la connaissance tirée de cette thèse souligne que la variabilité des tâches dans l’industrie automobile nécessite une approche ergonomique qui partage les connaissances des risques entre les intervenants. Dans cette approche, les attitudes et les comportements des opérateurs sont pris en compte dans les projets d’amélioration continue. De plus, la participation des intervenants devrait être intégrée afin d'améliorer la prise en compte de l'ergonomie dans la production. Une synthèse de cette thèse en Français a été fournie dans l’annexe première. / Musculoskeletal risk factors such as physical, organizational and psychosocial factors are a common challenge for the automotive assembly industries and result in adverse human and system effects. Ergonomics has already been integrated inthe production systems of such factories to eliminate work related musculoskeletal disorders (WR-MSDs). The issue is whether the current ergonomic approach of car industries, based on corporate standards and observational methods, can provide a shared knowledge of ergonomic factors for various stakeholders and facilitate ergonomic improvement. This study focuses on the positioning of the different assessment methods (used by various stakeholders), agreement between their results in evaluation of physical risk factors and the influence of intervention and improvement following ergonomic assessment. This thesis proposes that the current procedure of risk factor assessment can not provide ashared knowledge and representation of risks between stakeholders in manufacturing industries. It was found that the operators’ assessments of risk factors (self-reported questionnaire) were significantly different from those assessed by observational methods (ergonomist) and direct measurement. However, the operators’ opinions and judgments of ergonomic factors of a job are of particular importance to the success of an ergonomic approach. A structured interview based on objective data (video-observation or direct measurement) linked the activities and strategies of atrisk operators might be an appropriate procedure to advance ergonomics.The knowledge gained from this study emphasizes that the variable nature of tasks in manufacturing industries needs an ergonomic approach which shares knowledge and representation of risks between stakeholders. In such an approach, attitudes and behaviors of operators are taken into consideration in developing new intervention processes, organizational and technical remedies. Moreover, involvement of stakeholders should be integrated and this should result in improving production ergonomics.

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