Indiana University-Purdue University Indianapolis (IUPUI) / Design optimization of composite structures is of importance in the automotive, aerospace, and energy industry. The majority of optimization methods applied to laminated composites consider linear or simplified nonlinear models. Also, various techniques lack the ability to consider the composite failure criteria. Using artificial neural networks approximates the objective function to make it possible to use other techniques to solve the optimization problem. The present work describes an optimization process used to find the optimum design to meet crashworthiness requirements which includes minimizing peak crushing force and specific energy absorption for a square tube. The design variables include the number of plies, ply angle and ply thickness of the square tube. To obtain an effective approximation an artificial neural network (ANN) is used. Training data for the artificial neural network is obtained by crash analysis of a square tube for various samples using LS DYNA. The sampling plan is created using Latin Hypercube Sampling. The square tube is considered to be impacted by the rigid wall with fixed velocity and rigid body acceleration, force versus displacement curves are plotted to obtain values for crushing force, deceleration, crush length and specific energy absorbed. The optimized values for the square tube to fulfill the crashworthiness requirements are obtained using an artificial neural network combined with Multi-Objective Genetic Algorithms (MOGA). MOGA finds optimum values in the feasible design space. Optimal solutions obtained are presented by the Pareto frontier curve. The optimization is performed with accuracy considering 5% error.

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Människor lämnar alla efter sig ett miljöavtryck när man inhandlar matvaror. Hur stort miljöavtryck man upplever att man lämnar efter sig är dock inte alltid korrekt. Syftet med studien var att undersöka om upplevelsen av en köprundas miljöavtryck påverkas särskilt av huruvida köprundan inleds med ett miljövänligt val eller avslutas med ett miljövänligt val. Detta för att få en bredare förståelse om kognitiva mekanismer som ligger till grund för miljörelaterat beteende. I denna kvantitativa studie så studerades psykologin i människors upplevelse av miljöpåverkan genom att undersöka hur miljömärkning påverkar upplevelsen av miljöavtryck från konsumentval. Studien undersökte ifall miljömärkta varor har större effekt på denna upplevelse om de märkta varorna inhandlas i början eller i slutet i en sekvens av inköp. Detta utfördes genom ett digitalt test som 32 deltagare (17 kvinnor, 15 män) vars ålder var mellan 22 och 63 år (M=32,31 år, SD=10,92) fick delta i och skattade sin miljöpåverkan som deltagarna tror att varorna hade under den fiktiva köprundan. Genom att undersöka ifall ordningen från första eller sista miljövalet har betydelse så får man en primacy eller en recency effekt. Denna studie indikerar på att under en köprunda när den avslutas med ett miljövänligt val så kommer människor uppleva att ens köprunda har lägre miljöavtryck i sin helhet. Studien visar alltså på en recency effekt samt duration neglect, däremot ingen primacy effekt. / Every single person who buys food products leave an environmental footprint. How big of an environmental footprint you feel you leave behind is not always accurate. The purpose of the study was to examine whether the experience of a shopping round's environmental footprint is particularly affected by whether the shopping round begins with an environmentally friendly choice or ends with an environmentally friendly choice. This is to gain a broader understanding of cognitive mechanisms which are the basis of environmental behaviour. In this quantitative study, the psychology of people's experience of environmental impact were studied by examining how environmental labelling affects the experience of environmental footprint from consumer choices. The study examines whether eco-labelled goods have a greater effect on this experience if the labelled goods are purchased at the beginning or at the end of a sequence of purchases. This is done through a digital test that 32 participants (17 women, 15 men) aged between 22 and 63 years (M=32,31 år, SD=10,92) can take part in where they estimate their environmental impact that the participants think the goods have had during the fictitious shopping round. By checking the order, if the first or last choice is important, you get a primacy or a recency effect. This study indicates that during a shopping spree when it ends with an environmentally friendly choice, people will experience that one's shopping spree has a lower environmental footprint as a whole. The study thus shows a recency effect and a duration neglect, but no primacy effect.

The ionospheric peak electron density NmF2, simulated with the Coupled Thermosphere Ionosphere Plasmasphere electrodynamics (CTIPe) model was used to study the ionospheric response to solar flux in years of low (2008) and high (2013) solar activity. The CTIPe NmF2 was compared to the Whole Atmosphere Community Climate Model with Thermosphere and Ionosphere Extension (WACCM-X) and the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) NmF2 in March and July of 2008 and 2013. The comparison shows that the CTIPe NmF2 is lower than the COSMIC andWACCM-X NmF2. Both models successfully reproduce the semi-annual variations seen in the COSMIC observations. Analysis of the 27-day variations of the CTIPe NmF2 shows that the midnight NmF2 deviations are stronger than the midday deviations. In addition, at low solar activity, the 27-day variations of NmF2 are larger in the Southern Hemisphere, while at high solar activity, the 27-day variations of NmF2 are larger at the equator and in the Northern Hemisphere. An ionospheric delay was estimated with CTIPe simulated NmF2 at the 27-day solar rotation period during low and high solar activity. During low (high) solar activity, an ionospheric delay of about 12 (34) hours is predicted indicating an increasing ionospheric delay with solar activity. / Die maximale ionosphärische Elektronendichte NmF2, die mit dem Coupled Thermosphere Ionosphere Plasmasphere electrodynamics (CTIPe) Modell simuliert wurde, wurde zur Untersuchung der ionosphärischen Reaktion in Jahren mit geringer (2008) und hoher (2013) Sonnenaktivität verwendet. CTIPe vorhergesagte NmF2 wurde mit derjenigen des Whole Atmosphere Community Climate Model with Thermosphere and Ionosphere Extension (WACCM-X) und Messwerten des Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) im März und Juli der Jahre 2008 und 2013 verglichen. Der Vergleich zeigt, dass NmF2 aus CTIPe geringer ist als das COSMIC gemessene und von WACCM-X simulierte. Beide Modelle reproduzieren erfolgreich die von COSMIC beobachteten halbjährlichen Schwankungen. Die Analyse der 27-tägigen Schwankungen des CTIPe NmF2 zeigt, dass die mitternächtlichen NMF2-Abweichungen stärker sind als diejenigen am Mittag. Außerdem sind bei geringer Sonnenaktivität die 27-Tage-Abweichungen von NmF2 in der Südhemisphäre größer, während bei hoher Sonnenaktivität die 27-Tage-Abweichungen von NmF2 am Äquator und in der Nordhemisphäre größer sind. Die ionosphärische Verzögerung während geringer und hoher Sonnenaktivität wurde für die 27-tägige Sonnenrotation mit CTIPe simuliert. Bei geringer (hoher) Sonnenaktivität wird eine ionosphärische Verzögerung von etwa 12 (34) Stunden beobachtet, was auf eine zunehmende ionosphärische Verzögerung mit zunehmender Sonnenaktivität hinweist.

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Purpose: This study examined voice onset time (VOT) in children with and without vocal fold nodules (VFN). The purpose of this study was to provide further evidence regarding the need for individualized research and treatment dedicated to the pediatric population. The pediatric population has a distinctly different laryngeal mechanism than adults, as they are still developing. Although the pediatric system is anatomically different from that of a fully mature adult system, treatment for children with VFN is largely based on adult research. This study examined the VOTs of voiceless consonants, as the transition from the voiceless consonant to the subsequent vowel requires significant vocal and articulatory control and coordination. Measures of VOT change throughout the maturation as VOT follows a significant developmental pattern. Children with and without VFN were enlisted in order to examine the effects VFN have on VOT. Hypotheses: We hypothesize that children with VFN would have differences in 1) average VOT values compared to the control group, with no prediction for direction of difference (shorter and longer), and 2) between-word variability of VOT values compared to the control group, with no prediction for direction of difference (more variable and less variable). Methods: Participant data were retrospectively collected and included children between 6 and 12 years old with VFN and age- and sex-matched controls. Participants were recorded producing the six CAPE-V sentences. Four voiceless consonants were selected for VOT analysis. Praat was utilized to manually mark the vocal onset of the stop consonant by the current researcher. A previous researcher identified the vocal offset, and each placement was confirmed by the current researcher. VOT was calculated as the time between the stop consonant burst and the vocal onset of the vowel. Results: There was no significant difference between the VFN and the control groups in average VOT or VOT variability. Within the VFN group, participants who were more dysphonic (lower cepstral peak prominence (CPP) values) had more variable VOT values. Participants in the VFN group had lower CPP values than the control group, suggesting that CPP measures are a reliable indicator of dysphonia. Additionally, within the VFN group, male children had lower CPP values than female children. Conclusion: Although no group difference was found, the within-group analyses indicated that VFNs impacted productions. Children with VFN who were more dysphonic had increased VOT variability. This may suggest that VFN impact a child’s ability to phonate therefore causing more variability within productions. Future research is needed to study the impact dysphonia treatment for children with VFN may have on VOT values. Additionally, a longitudinal study of the impact of VFNs on VOT values during developmental stages may be warranted. / Public Health

Foot strike type affects running mechanics and may influence overuse injury occurrence. Measuring the interaction between cumulative load and foot strike type may provide additional information that could eventually help with understanding injury mechanisms. The purpose of this study was to determine how foot strike type affects cumulative loading in runners, and to determine if individual metrics change throughout a 5-kilometer sub-maximal run. 30 participants ran on an instrumented treadmill for 5 km at 3.15 m/s with their preferred foot strike type (14 rearfoot strike, 16 non-rearfoot strike). Stride rate, foot strike angle, loading rate, per stride and per km (cumulative) vertical ground reaction force impulse, impact peak, absolute peak, knee negative work, and ankle negative work were calculated and compared across time and between groups. Per stride between-group main effects were seen for stance time (p=0.003), foot strike angle (p<0.001), and loading rate (p=0.040), all of which were greater for rearfoot strike runners. Per stride and cumulative ankle and knee negative work also showed significant differences, with ankle negative work being greater for non-rearfoot strike runners (p=<0.001 per stride, p=<0.001 cumulative) and knee negative work being greater for rearfoot strike runners (p=0.014 per stride, p=0.008 cumulative). Both loading rate and cumulative vertical ground reaction force impulse decreased significantly over time (p=0.035, p=<0.001 respectively). In summary, we found a few differences in per stride and cumulative metrics between foot strike groups, namely ankle and knee loading as previously observed. However, as a whole, individual variability in vertical ground reaction force loading patterns was more apparent than any group distinctions. We also found patterns in previous research suggesting that study design components, specifically self-selected speed and habituation, affect variables such as stride rate and peak vertical ground reaction force. The common perception that non-rearfoot strike runners have a higher stride rate was not supported in this study. Lastly, we determined that cumulative calculations can be different if taken at the beginning vs the end of a run. Quantifying injury risk is complicated and cumulative damage models should take into account individual load capacity and training session characteristics (e.g., warm-up time, length, intensity, and rest time).

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