4,268 research outputs found
Alguns elements per a la motivació. Aspectes que desperten l’interès per les matemàtiques a l'aula
La motivació dels estudiants a les aules és un tema que preocupa a tots els professors de
l’ensenyament. L’ideal seria que es pogués respondre a la pregunta “com es pot fer
perquè els alumnes estiguin interessats a les aules?”
Aquesta resposta encara no s’ha trobat, i tot apunta a que no sigui una resposta fàcil. En
aquest treball es defineix un concepte clau dins el que és la motivació: la motivació
intrínseca. Aquest tipus de motivació és la que fa que la gent faci activitats “perquè vol” i
no perquè hi ha algun element extern que la força a fer-ho. A la definició es tracta de
descriure, segons diferents autors, els components en que es pot dividir aquesta
motivació.
Al treball també es destaquen dos aspectes que controlen la motivació dels alumnes: el
valor que donen als seus objectius i les atribucions causals que realitzen d’allò que
perceben. Es proposen algunes actuacions a l’aula encarades a aprofitar aquests aspectes.
S’ha fet també un breu estudi sobre dos tipus d’activitats de tipus no estàndard per a
realitzar a l’aula. Per una banda, els problemes contextualitzats en les quals es basa la
teoria de l’Educació Matemàtica Realista de l’escola Freudenthal, dels quals a la secció
final del treball es porta una activitat concreta a l’aula, i d’altra banda, l’aprenentatge per
projectes.
A més, s’analitzen dues classes de matemàtiques a aules reals, identificant els elements de
motivació utilitzats per professors diferents.
Per últim, es descriu una activitat concreta que s’ha portat a l’aula: “L’aritmètica del
rellotge”. És, com s’ha dit, del tipus “problema contextualitzat”. S’ha fet un petit anàlisi de
l’actuació i de la valoració de l’activitat per part dels alumnes mitjançant una enquesta
que han respost a l’aula
The acute effects of different blood flow restriction settings on blood lactate, electromyography and leg strength during bilateral knee extensions
The current protocols being used for Blood Flow Restriction (BFR) exercise did not examine the effects of different Initial Restrictive Pressures (pressure applied to limb by cuff prior to inflation, IRP) during design. There are several research articles highlighting the importance of IRP and how it can create variability in results. Therefore it is necessary to evaluate the current BFR protocol against different IRP in order to determine reliability. PURPOSE: The purpose of this study was to examine the acute effects of different blood flow restriction setting on 1) the level of blood lactate production, 2) neuromuscular activation (the changes in motor unit activation and median frequency), and 3) fatigue response during bilateral knee extension exercise. METHODS: Thirty-three male (age= 26.63 (5.8), n=17) and female (age= 22.76 (3.3), n=16) participants performed four sets of bilateral knee extensions on four separate occasions separated by at least 48 hours. Each session was randomized into the following conditions: IRP50@FRP+20, IRP65@FRP-20, IRP50 (Control), and IRP65. During each condition, blood pressure (BP), heart rate (HR), rate of perceived exertion (RPE), discomfort/pain (DF), and blood lactate were recorded throughout the study. Maximal voluntary contraction (MVC) was recorded pre and post exercise. Electromyography was recorded at the vastus lateralis and rectus femoris with a focus on motor unit activation (RMS) and muscle firing rate (MDF). RESULTS: No significant difference was found between conditions for BP, blood lactate or RPE. HR displayed a condition*gender interaction (p=0.022) and a trend for a condition*time interaction (p\u3c0.06). IRP65@FRP-20 displayed a trend for increased levels of DF (p=0.062); it also produced significantly higher decreases in pre to post MVC in both males and females (p\u3c0.023), showing a strong trend for a greater effect in males (p=0.055). IRP65@FRP-20 further displayed greater levels of overall motor recruitment in the vastus lateralis (p=0.024) as well as greater levels of motor recruitment throughout sets 2-4 in the vastus lateralis (p\u3c0.01) and rectus femoris (p\u3c0.01). CONCLUSION:IRP65@FRP-20 created greater variations amongst the variables compared to the Control, despite having a lower final restrictive pressure. This suggests that the current protocol may not be the most reliable method of BFR. Further research is needed to develop a protocol that takes IRP into account
Approach to acoustic mapping through continuous mobile monitoring
For the production of representative noise maps, a large amount of information is necessary, which includes, among others, on-site measurements of environmental noise. Thus, for noise maps based on measurements, mobile sampling emerges as a possible solution for the enhancement of data acquisition.
The present research proposes a complete framework to perform mobile sampling. Since the normative requires long-term values to be presented in a noise map, a sampling strategy based on temporal stratification, which reduces the required sampled days to estimate the annual equivalent noise level, is presented. Furthermore, to compute long-term values for the night period, since they are usually affected by noise sources different to traffic, specifically leisure noise, a complementary temporal and spatial stratification is also presented.
Then, the statistical requirements to perform mobile noise measurements using bicycles is evaluated. The vehicles and bicycles journeys are reproduced based on micro-traffic simulation and then coupled with an acoustic modeling. The estimation error of LAeq for the mobile sampling is compared to reference static samples, in terms of the Root Mean Square Error (RMSE), and is computed for different aggregation radius of mobile receivers, and as a function of the number of passes-by and to the distance to its nearest cross street.
To perform the mobile sampling on a real scenario, a low-cost noise monitoring device with the aim of performing georeferenced noise sampling, is developed. The accuracy tests suggest that it is able to acquire noise levels with an equivalent accuracy as a Class 2 sound level meter.
Finally, to validate the results obtained through the modeling framework, a noise monitoring device is mounted on a bicycle and on-site mobile measurements are performed simultaneously to reference static ones. The same scenario is again recreated based on micro-simulation of traffic complemented with acoustic modeling. Then, for the simulated framework and the on-site measurements, the RMSE of the estimation of LAeq for different aggregation radius of mobile samples is compared to the reference static ones. It is confirmed that mobile sampling is a solution to improve noise data acquisition, which reduces the resources required to produce a noise map without sacrificing the accuracy and representativeness.Para la producción de mapas de ruido representativos, una gran cantidad de información es necesaria, que incluye, entre otras, mediciones de ruido ambiental en sitio. Por lo tanto, para los mapas de ruido basados en mediciones, el muestreo móvil surge como una posible solución para mejorar la adquisición de datos. La presente investigación propone un marco completo para realizar el muestreo móvil. Dado que la normativa requiere de valores de largo plazo para realizar un mapa de ruido, se propone una estrategia de muestreo basada en estratificación temporal que reduce los días de muestreo necesarios para estimar el nivel de ruido equivalente anual. Además, para calcular los valores a largo plazo para el período nocturno, ya que generalmente se ve afectado por fuentes de ruido distintas al tráfico, específicamente de ruido de ocio, se presenta una estratificación temporal y espacial complementaria. Por otra parte, se evalúan los requisitos estadísticos para realizar mediciones de ruido móviles utilizando bicicletas. Los trayectos de los vehículos y las bicicletas se reproducen en base a una microsimulación de tráfico para después combinarse con modelado acústico. El error de estimación del indicador LAeq calculado con el muestreo móvil se compara, en términos del error cuadrático medio (RMSE), con muestras de referencia obtenidas de forma estática para diferentes radios de agregación de receptores móviles, y también en función del número de pases y de la distancia al cruce de calles más cercano. Para realizar el muestreo móvil en un escenario real, se desarrolla un dispositivo de monitoreo de ruido de bajo costo con el objetivo de realizar un muestreo de ruido georreferenciado. Las pruebas de precisión muestran que es capaz de adquirir niveles de ruido con una precisión equivalente a un sonómetro de Clase 2. Finalmente, para validar los resultados obtenidos a través de las simulaciones, se equipa una bicicleta con el dispositivo de monitoreo y se realizan mediciones móviles en sitio al mismo tiempo que mediciones estáticas de referencia. El mismo escenario se recrea basándose nuevamente en una microsimulación de tráfico complementada con modelado acústico. Después, para los niveles de ruido simulados y las mediciones en sitio, el RMSE de la estimación del indicador LAeq para distintos radios de agregación de muestras móviles se compara con el muestreo estático de referencia. Con ello, se confirma que el muestreo móvil es una solución para mejorar la adquisición de datos de ruido, lo que reduce los recursos necesarios para producir un mapa de ruido sin sacrificar la precisión y la representatividad.Postprint (published version
Cyber Situational Awareness and Cyber Curiosity Taxonomy for Understanding Susceptibility of Social Engineering Attacks in the Maritime Industry
The maritime information system (IS) user has to be prepared to deal with a potential safety and environmental risk that can be caused by an unanticipated failure to a cyber system used onboard a vessel. A hacker leveraging a maritime IS user’s Cyber Curiosity can lead to a successful cyber-attack by enticing a user to click on a malicious Web link sent through an email and/or posted on a social media website. At worst, a successful cyber-attack can impact the integrity of a ship’s cyber systems potentially causing disruption or human harm. A lack of awareness of social engineering attacks can increase the susceptibility of a successful cyber-attack against any organization. A combination of limited cyber situational awareness (SA) of social engineering attacks used against IS users and the user’s natural curiosity create significant threats to organizations.
The theoretical framework for this research study consists of four interrelated constructs and theories: social engineering, Cyber Curiosity, Cyber Situational Awareness, and activity theory. This study focused its investigation on two constructs, Cyber Situational Awareness and Cyber Curiosity. These constructs reflect user behavior and decision-making associated with being a victim of a social engineering cyber-attack. This study designed an interactive Web-based experiment to measure an IS user’s Cyber Situational Awareness and Cyber Curiosity to further understand the relationship between these two constructs in the context of cyber risk to organizations. The quantitative and qualitative data analysis from the experiment consisting of 174 IS users (120 maritime & 54 shoreside) were used to empirically assess if there are any significant differences in the maritime IS user’s level of Cyber SA, Cyber Curiosity, and position in the developed Cyber Risk taxonomy when controlled for demographic indicators.
To ensure validity and reliability of the proposed measures and the experimental procedures, a panel of nine subject matter experts (SMEs) reviewed the proposed measures/scores of Cyber SA and Cyber Curiosity. The SMEs’ responses were incorporated into the proposed measures and scores including the Web-based experiment. Furthermore, a pilot test was conducted of the Web-based experiment to assess measures of Cyber SA and Cyber Curiosity. This research validated that the developed Cyber Risk taxonomy could be used to assess the susceptibility of an IS user being a victim of a social engineering attack. Identifying a possible link in how both Cyber SA and Cyber Curiosity can help predict the susceptibility of a social engineering attack can be beneficial to the IS research community. In addition, potentially reducing the likelihood of an IS user being a victim of a cyber-attack by identifying factors that improve Cyber SA can reduce risks to organizations. The discussions and implications for future research opportunities are provided to aid the maritime cybersecurity research and practice communities
Evaluation of the cutaneous microbiome in psoriasis
Psoriasis, a highly prevalent disease of humans of unknown cause, is a chronic inflammatory disorder primarily involving skin, with distinctive clinical characteristics. With the newly developed tools that facilitate microbiome research, it now is possible to assess whether the cutaneous microbiome plays a role in the pathogenesis of this disorder. Preliminary data from our studies suggest that the cutaneous microbiome in psoriasis is complex and possibly different from normal. To deal with this complexity, we propose to examine the cutaneous microbiome in relation to psoriasis with explorations at several taxonomic and informatic levels. Our overall objective is to examine how changes in the normal cutaneous microbiome contributes to the pathogenesis of psoriasis. Since causality is complex and often difficult to prove, our overall hypothesis is that there are alterations in the cutaneous microbiome in areas of skin affected by psoriasis in comparison with the range observed in clinically unaffected areas, or in healthy persons. We also hypothesize that the characteristics of the microbiome may affect clinical responses to the immunomodulatory agents used to treat psoriasis. An alternative hypothesis is that effective treatment of psoriasis with systemic immunomodulatory agents will not substantially affect the disordered microbial ecosystem. Such observations would provide evidence for the roles of the microbiota in this disorder. Since an important consideration in microbiome research is the optimal level (e.g. phylum, genus, species, strain, gene) at which to examine a scientific question, and we are not yet certain what are the optimal levels for psoriasis, this also will be examined. Our studies of psoriasis should allow development of both approaches and tools that will have general utility for microbiome research. To test our hypothesis, we propose the following specific aims: 1. To understand the cutaneous microbiome species composition overlaying psoriatic lesions; 2. To investigate differences in metagenome content for psoriatic lesions compared to normal skin; 3. To identify differences in the transcriptional profiles of the microbiome and the host between normal skin and psoriatic lesions using high-throughput sequencing; and 4. To estimate the effects of systemic immunomodulatory therapy for psoriasis on microbiome composition. In total, these studies should help us understand the role of the microbiome in psoriasis pathogenesis
Biased Perceptions of Income Distribution and Preferences for Redistribution: Evidence from a Survey Experiment
Individual perceptions of income distribution play a vital role in political economy and public finance models, yet there is little evidence regarding their origins or accuracy. This study examines how individuals form these perceptions and posits that systematic biases arise from the extrapolation of information extracted from reference groups. A tailored household survey provides original evidence on the significant biases in individuals’ evaluations of their own relative position in the distribution. Furthermore, the data supports the hypothesis that the selection process into the reference groups is the source of those biases. Finally, this study also assesses the practical relevance of these biases by examining their impact on attitudes towards redistributive policies. An experimental design incorporated into the survey provides consistent information on the own ranking within the income distribution to a randomly selected group of respondents. Confronting agents’ biased perceptions with this information has a significant effect on their stated preferences for redistribution. Those who had overestimated their relative position and thought of themselves relatively richer than they were demand higher levels of redistribution when informed of their true ranking. This relationship between biased perceptions and political attitudes provides an alternative explanation for the relatively low degree of redistribution observed in modern democracies.preferences for redistribution, limited information, perceptions of income distribution, field experiment
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