A functional and effective alarm signal is a critical component of alarm systems designed to alert workers of impending danger. In a previous study (Hansson, 2017) background alarm sirens composed of changing-state sounds with an embedded temporal deviant, produced greater disruption of serial short-term memory than a signal without a deviant. However, to give rise to disruption the siren needed to change from fast to slow, since a change from slow to fast was impotent in its effect on task performance. In the current study, whether acoustic change was a necessary prerequisite for obtaining the fast-to-slow deviant effect was explored. Thus, repeated tones—steady-state sequences—presented at slow or fast rates were used with or without a temporal deviant (change from slow-to-fast vs. change from fast-to-slow). In the context of the steady-state sequences, both slow-to-fast and fast-to-slow temporal deviants produced disruption relative to the fast and slow control sequences. This suggests that a changing-state sequence is required for the fast-to-slow temporal deviant effect to arise. However, an alternative explanation based upon inter-stimulus intervals is also entertained. Understanding the acoustic parameters of sound is necessary to develop alarms sirens that are better at capturing attention. The current study suggests that embedding temporal deviants within sirens can promote greater attentional capture, but that this may depend on the nature of the alarm signal (whether it is changing vs. steady-state) and the direction of the change of speed (slow-to-fast vs. fast-to-slow).

Alarm signals such as sirens are crucial in alerting users of impending dangers. Therefore, it is important that the siren is designed so it can capture user's attention. In a previous study (Hansson, 2017) background alarm sirens composed of changing-state sounds with an embedded temporal deviant, produced greater disruption of serial short-term memory than a signal without a temporal deviant. However, to give rise to disruption the siren needed to change from fast to slow, since a change from slow to fast was impotent in its effect on task performance. This was further addressed in Hansson (2018) where it was shown that acoustic change appeared to be a necessary prerequisite for obtaining the fast-to-slow temporal deviant effect: When steady-state sounds were used fast-to-slow and or slow-to-fast temporal deviants were equally disruptive of serial recall. However, in order to create a steady-state siren, inter-stimulus intervals were incorporated into the siren to prevent the continuous uninterrupted presentation of a single tone. Since inter-stimulus intervals were not used in Hansson (2017) it could be the presence of these that eliminated the potency of the fast-to-slow over the slow-to-fast temporal deviation effect in Hansson (2018). Therefore, the current study was undertaken to investigate whether the embedding inter-stimulus intervals within a changing-state siren would restore the potency of the fast-to-slow temporal deviation over the slow-to-fast temporal deviation in capturing attention. The additional disruption for fast-to-slow temporal deviants over slow-to-fast temporal deviants (that did not produce disruption relative to control) returned in the current study when inter-stimulus intervals were included within the siren. The results support the notion that the additional disruption produced by fast-to-slow, over slow-to-fast temporal deviants depend on the changing-state properties of the siren. Implications of this result for the design and operation of sirens within ecologically valid settings are discussed.

Orientador: Camila Coelho Greco / Banca: Mauro Gonçalves / Banca: Luiz Guilherme Antonacci Guglielmo / Resumo: O principal objetivo deste estudo foi comparar a velocidade, concentração de lactato sanguíneo e os índices técnicos correspondentes à máxima fase estável de lactato sanguíneo obtida de forma contínua e intermitente na natação. Participaram deste estudo, 5 nadadores fundistas e 8 triatletas (23 + 9 anos, 1,76 + 0,1 m e 71,3 + 9,8 kg), com pelo menos 3 anos de experiência nas respectivas modalidades. Os indivíduos realizaram em diferentes dias, os seguintes testes, em uma piscina de 25 m: 1) repetição máxima na distância de 400 m; 2) teste incremental para a determinação do limiar de lactato (LL) e limiar anaeróbio (LAn); 3) 2 a 4 repetições com duração de 30 min em diferentes intensidades, para a determinação da máxima fase estável de lactato sanguíneo contínua (MLSSC), e; 4) 2 a 4 tentativas de 12 x 150 s com intervalo de 30 s (5:1) em diferentes intensidades, para a determinação da máxima fase estável de lactato sanguíneo intermitente (MLSSI). O LAn foi determinado por meio de interpolação linear entre a velocidade e a concentração de lactato, considerando uma concentração fixa de lactato de 3,5 mM. O critério de determinação da MLSSC e da MLSSI foi um aumento menor ou igual a 1 mM de lactato entre o décimo e o trigésimo min de exercício. Os índices técnicos taxa de braçada (TB), comprimento de braçada (CB) e índice de braçada (IB) foram determinados em todos os testes. A TB foi calculada por meio de filmagem utilizando o tempo necessário para se realizar cinco ciclos completos de braçadas. O CB foi calculado dividindo a velocidade pela TB. O IB foi determinado pelo produto da velocidade e o CB. De acordo com os dados do presente estudo, a máxima fase estável de lactato sanguínea é atingida em uma velocidade maior quando esta é determinada de forma intermitente (1,17 + 0,09 m.s-1) do que de forma contínua (1,13 + 0,08 m.s-1)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The main objective of this study was to compare the speed, blood lactate concentration and technical indexes corresponding to the maximal lactate steady state obtained with continuous and intermittent protocols. Thirteen endurance swimmers and triathletes (23.8 ± 9.5 yr., 1.76 ± 0.1 m and 71.3 ± 9.8 kg) participated of this study. The athletes had at least 3 years of experience in swimming. The individuals performed in different days, the following tests: 1) Maximal performance tests of 400 m; 2) Progressive test until exhaustion to determine the anaerobic threshold (AT); 3) 2 to 4 30-min repetitions in different intensities, to determine continuous maximal lactate steady state (MLSSC), and; 4) 2 to 4 trials of 12 x 150 s with 30 s of rest (5:1) at different intensities, to determine the intermittent maximal lactate steady state (MLSSI). The AT was determined trough linear interpolation between the speed and blood lactate concentration, considering a fixed blood lactate value of 3.5 mM. The criterion for the determination of MLSSC and MLSSI was an increase lower or equal to 1 mM of lactate between tenth and thirty min of exercise. Technical indexes stroke rate (SR), stroke length (SL) and stroke index (SI) were determined in all tests. The TB was calculated trough film using the time to perform five complete stroke cycles. The CB was calculated trough the quotient between the speed and SR. The SI was determined by the product of the speed and SL... (Complete abstract click electronic access below) / Mestre

O trabalho apresentado nesta dissertação consiste do estudo do comportamento direcional de um veículo comercial de 2 eixos, classificando-o quanto a sua estabilidade (Oversteer, Understeer ou Neutral Steer) e predizendo em que condições sua instabilidade torna-se crítica. para esta finalidade, o veículo foi modelado desenvolvendo uma trajetória curvilínea de raio constante em situação de regime permanente e uma rotina de cálculos representa sua dinâmica lateral. O recurso computacional utilizado (software Excel) foi propositadamente escolhido tendo como premissa ser o mais simples possível, para que os custos e tempo envolvidos fossem mínimos. Foram realizadas algumas medições com o veículo em questão e, levando-se em conta todas as simplificações implementadas, os resultados práticos e teóricos demonstraram correlação satisfatória. Desta maneira, então, pode-se dizer que o instrumento desenvolvido neste trabalho pode ser aplicado como um recurso valioso durante a fase inicial de conceituação da suspensão de um veículo de 2 eixos, principalmente tratando-se de uma avaliação comparativa com veículos semelhantes já testados. / The work presented consists of a 2 axles light truck directional behavior evaluation, where computational resources applied are very simple and easy hand (software excel). Steady state cornering concept was used to get its stability classification (Oversteer, Understeer or Neutral Steer) and show in which moment its behavior become unstable. Experimental measurements took place and the practical (measured) and theoretical (came from the developed model) results showed theirselves satisfactory, considering all the simplifications. Thus, this procedure might be useful during a two axle light truck suspension development, ultimately if is adopted to compare with another one already known. Costs and time are saved in this way.

Dissertação (Mestrado em Engenharia Mecânica) - Centro Universitário FEI, São Bernardo do Campo, 2016.

The two most common methods to measure resting metabolic rate using indirect calorimetry are steady state or time interval. Steady state is commonly defined as the first five minutes in which oxygen consumption and carbon dioxide production vary by <10%. A time interval measurement generally lasts 20-60 minutes. Using steady state criteria is often harder to achieve, but many suggest it more accurately measures resting metabolic rate. Our objective was to determine if there were differences between steady state and time interval measurements in a healthy adult population. Seventy seven subjects were measured for 45 minutes. Inclusion criteria included healthy subjects ages 18-65, excluding pregnant and lactating women. Paired t-tests analyzed differences between measures, and Bland-Altman plots evaluated bias, precision, and accuracy. Of 77 subjects, 84% achieved steady state, and 95% achieved SS by minute 30. Most differences between steady state and time intervals were statistically but not practically significant. Bland-Altman plots showed steady state measurements were generally lower indicating that steady state is more indicative of resting metabolic rate. Minutes 6-25 were most precise, accurate and fairly unbiased compared to steady state. We recommend measuring a subject for 30 minutes and using steady state criteria of <10% variation of oxygen consumption and carbon dioxide production for five minutes if a subject is able to achieve it. However, if a subject cannot achieve steady state, we recommend averaging minutes 6-25.

This study explores the reactions and related species of NOx pollutants in methane flames in order to understand their production and consumption during the combustion process. To do this, several analytical simulations were run to explore the behavior of nitrogen species in the pre-flame, post- flame, and reaction layer regions. The results were then analyzed in order to identify all "steady-state" species in the flame as well as the determine all the unnecessary reactions and species that are not required to meet a defined accuracy. The reductions were then applied and proven to be viable.

Various directional comparison bus protection methods including widely used superimposed directional element method need to have both voltages and currents from all feeders connected to the zone of protection to find the direction of current for detecting a bus fault or a line fault. The purpose of the thesis is to present a new technique for directional comparison bus protection to discriminate a bus fault from line fault and normal condition. The new technique, which is implementing superimposed directional element method to modify partial operating current characteristics (POC) method to superimposed POC (SPOC) method, does not use voltages from feeders, hence capacitor voltage transformers (CVTs) are no longer needed in the zone of protection. The proposed technique was implemented in 4-bus and IEEE 14-bus test system and was tested using different fault cases including CT saturation and high impedance fault. The proposed technique, SPOC method was compared with POC method with both methods implemented in same test systems and tested with same fault cases. The results show that the proposed technique is successful to detect bus faults with high accuracy and high speed.

In this thesis, we will study bio-mathematics. We will introduce differential equations, biological applications, and simulations with emphasis in molecular events. One of the first courses of action is to introduce and construct a mathematical model of our biological element. The biological element of study is the Hepatitis C virus. The idea in creating a mathematical model is to approach the biological element in small steps. We will first introduce a block (schematic) diagram of the element, create differential equations that define the diagram, convert the dimensional equations to non-dimensional equations, reduce the number of parameters, identify the important parameters, and analyze the results. These results will tell us which variables must be adjusted to prevent the Hepatitis C virus from becoming chronic.

Cette thèse, à la fois numérique et expérimentale, porte sur l’étude du transfert de chaleur par convection naturelle qui apparait au sein d’une cavité hémisphérique en régime stationnaire. L’enceinte est remplie d’eau ou de nanofluide de type eau / ZnO. La fraction volumique varie entre 0 (eau pure) et 10%. La coupole de la cavité est maintenue à température froide. Ce travail s’applique au domaine de l’ingénierie électronique et plus particulièrement au refroidissement des composants actifs de différentes formes. Trois géométries de sources de chaleur sont étudiées : la première est plane et circulaire (disque) et les suivantes, centrées sur le disque, de même surface d’échange, sont cubique et hémisphérique. L’angle d’inclinaison du disque varie entre 0 (coupole orientée vers le haut) et 180° (coupole orientée vers le bas) par rapport au plan horizontal. Les sources de chaleur génèrent des puissances qui conduisent à des Rayleigh importants. L’approche numérique est effectuée à l’aide de la méthode des volumes finis basée sur l’algorithme SIMPLE et un modèle monophasique. Pour chaque source active, le transfert de chaleur convectif est analysé et quantifié par l’intermédiaire d’une corrélation du type Nusselt-Rayleigh-Prandtl-angle d’inclinaison. D’un point de vue expérimental, la fabrication des sources de chaleur est minutieusement décrite étape par étape et le calcul du coefficient de transfert convectif moyen expérimental est détaillé. La comparaison mesures-corrélations remet en question l’efficacité du nanofluide en termes de refroidissement. / This numerical and experimental thesis deals with natural convective heat transfer that occurs in a hemispherical cavity in steady state. The enclosure is filled with water or ZnO / water nanofluid. The volume fraction varies between 0% (pure water) and 10%. The coupola of the cavity is kept at a cold temperature. This work corresponds to the field of electronics and the cooling of different actives composants. Three active heating sources are studied: the first one is plane and circular (the disc) and the followings, centered on the disc with the same surface, are cubical and hemispherical. The tilted angle varies between 0 (dome facing upwards) and 180° (dome facing downwards) with respect to the horizontal plane. Heat sources generate important heat fluxes leading to high Rayleigh numbers values. Numerical approach is done by means of the volume control method based on the SIMPLE algorithm and using monophasic model. For each active source, the convective heat transfer is analyzed and quantified by means of a correlation of the Nusselt-Rayleig-Prandtl-tilt angle type. Experimentally, the heat sources are built step by step and the average convective heat transfer coefficient is calculated. The comparison measures-correlations questions on the cooling nanofluid’s efficiency.