Search results for "Design of experiment"
showing 10 items of 49 documents
El esfuerzo en el trabajo de los docentes: el impacto del experimento AGEMAD
2014
International audience; Utilizando datos de un experimento randomizado realizado en Madagascar durante dos años escolares completos, se evalúan las heterogeneidades de impacto de unas intervenciones específicamente diseñadas para mejorar la gestión del proceso pedagógico en la escuelas primarias. Nuestros resultados muestran que intervenciones intensivas y directas a lo largo de la jerarquía educativa permiten cambiar el comportamiento de los docentes de manera significativa. Sin embargo, el impacto medio del programa oculta una gran heterogeneidad. Los maestros que tenían pocos alumnos así como los que tenían unas buenas condiciones de trabajo se beneficiaron más de las mismas. Por el cont…
Actuar para mejorar la implicacion en el trabajo de los docentes: resultados diferenciados de un experimento randomizado
2013
En ligne sur http://2013.economicsofeducation.com/user/pdfsesiones/106.pdf?PHPSESSID=vg6pgcqhd5dl52aenlhacj17k6; International audience; Utilizando datos de un experimento randomizado realizado en Madagascar durante dos años escolares completos, se evalúan las heterogeneidades de impacto de unas intervenciones específicamente diseñadas para mejorar la gestión del proceso pedagógico en la escuelas primarias. Nuestros resultados muestran que intervenciones intensivas y directas a lo largo de la jerarquía educativa permiten cambiar el comportamiento de los docentes de manera significativa. Sin embargo, el impacto medio del programa oculta una gran heterogeneidad. Los maestros que tenían pocos …
Managerial Behavior in the Lab: Information Disclosure, Decision Process and Leadership Style
2019
This paper reports the results from a lab experiment in which subjects playing the manager role can implement either an efficient / inegalitarian allocation or an inefficient / egalitarian allocation of payoffs. The experiment simulates a stylized managerial context by allowing the manager to manipulate information and select the decision process and by allowing the stakeholders to retaliate against the manager given different choices in the decision process. We found that the inefficient allocation is often selected and that this choice depends on whether the employees can retaliate against the manager and on whether the manager can hide information about the payoffs. The social preference…
Study and evaluation of fretting critical slip conditions by applying the design of experiments method
2006
Tribological systems are complex systems that require a multi-disciplinary (mechanical, material, physico-chemical) approach where numerous influence factors can be involved. To characterize a contact couple, the intrinsic parameters of the materials as well as the parameters related to the contact loading and the surrounding environment need to be taken into account. Fretting analysis, by means of running condition-fretting maps (RCFM), allows the behavior of the contact couple to be taken into account and to predict the boundary between partial slip and gross slip conditions. This article presents the study of a steel/polycarbonate couple during fretting tests. The study was carried out b…
Get into flow: Design of experiments as a key technique in the optimization of anodic dehydrogenative C,C cross-coupling reaction of phenols in flow …
2021
Abstract The optimization of electro-organic reactions poses a challenge due to the various parameters involved. Quite often those parameters are not independent from each other, leading the experimental scientist using linear approaches into an optimization loophole. We report a strategy for the optimization of the anodic oxidative dehydrogenative C,C cross-coupling reactions for the synthesis of biphenols based on Design of Experiments (DoE), which overcomes the drawbacks of linear optimization approaches. Using a fractional design, we increased the yield of a long-time investigated example reaction from 44% up to 85% and point out different suitable reaction conditions through to linear …
FSW of AA2139-T8 Butt joints for aeronautical applications
2011
The effect of process parameters on mechanical and microstructural properties of AA 2139 T8 joints produced by friction stir welding (FSW) was analysed by means of statistical tools. Three different parameters were taken into account: angular speed ( ω), welding speed ( va), and plunging depth ( p); each of them was varied on three levels. Forces and temperatures achieved during the welding were monitored and analysed for all joints. An accurate microstructural analysis was performed: the occurrence of some remarkable defects, typical of FSW, such as tunnel or lack of penetration, was related to actual process parameters adopted. The extension of each FSW characteristic zone was measured a…
Relevant factors for the eco-design of polylactide/sisal biocomposites to control biodegradation in soil in an end-of-life scenario
2017
[EN] The eco-design considers the factors to prepare biocomposites under an end-of-life scenario. PLA/sisal biocomposites were obtained from amorphous polylactide and sisal loadings of 10, 20 and 30 wt% with and without coupling agent, and subjected to biodegradation in soil according to standard IS0846. Mass loss, differential scanning calorimetry and size-exclusion chromatography were used for monitoring biodegradation. A statistical factorial analysis based on the molar mass M-n, and crystallinity degree X-c pointed out the relevance and interaction of amount of fibre and use of coupling agent with the time of burial in soil., During the preparation of biocomposites, chain scission provo…
Experimental Study of the Laser Cutting Process on 1C45 - 3 mm Steel
2014
The Paper Presents the Measurement Systems Analysis, System Capability and Optimization of a Laser Cutting System for 3 Mm Alloy Steel. for the Measurement System Analysis and System Capability the Data was Introduced in a Excel Sheet which was Designed According to QS9000 Standard (Measurement System Analysis) to Calculate the Measuring System Repeatability, Reproducibility and Capability. Design of Experiment (DOE) was Used for Process Optimization the Optimization was Conducted in an Operational Manufacturing Environment and was Based on the Design of a 25 Full Factorial Experiment. the Laser Parameters (input) were Feed Rate v, Gas Pressure p, Power P, Frequency F and Efficiency R while…
Adaptive design optimization: a mutual information-based approach to model discrimination in cognitive science.
2010
Discriminating among competing statistical models is a pressing issue for many experimentalists in the field of cognitive science. Resolving this issue begins with designing maximally informative experiments. To this end, the problem to be solved in adaptive design optimization is identifying experimental designs under which one can infer the underlying model in the fewest possible steps. When the models under consideration are nonlinear, as is often the case in cognitive science, this problem can be impossible to solve analytically without simplifying assumptions. However, as we show in this letter, a full solution can be found numerically with the help of a Bayesian computational trick d…
A Comparison between Three Meta-Modeling Optimization Approaches to Design a Tube Hydroforming Process
2012
Computer aided procedures to design and optimize forming processes have become crucial research topics as the industrial interest in cost and time reduction has been increasing. A standalone numerical simulation approach could make the design too time consuming while meta-modeling techniques enables faster approximation of the investigated phenomena, reducing the simulation time. Many researchers are, nowadays, facing such research challenge by using various approaches. Response surface method (RSM) is probably the most known one, since its effectiveness was demonstrated in the past years. The effectiveness of RSM depends both on the definition of the Design of Experiments (DoE) and the acc…