By assimilating shape memory alloys with mathematical multifractal-type objects, a theoretical model based on Scale Relativity Theory in the form of The Multifractal Theory of Motion, in order to ...explain the mechanical behavior of such material, is proposed. The model is validated by analyzing the mechanical behavior of Cu-Al-Zn shape memory alloy with various chemical compositions. More precisely, the multifractal tunnel effect can "mime" the mechanical hysteresis of such a material, a situation in which a direct correspondence for several mechanical properties of Cu-Al-Zn is highlighted (the chemical composition can be correlated with the shapes of the curves controlled through the multifractality degree, while the areas delimited by the same curves can be correlated with the multifractal specific potential, as a measure of the mechanical memory degree).
People's inability to delay gratification and the tendency to discount rewards as a function of time has been used as an index of impulsivity and lack of self-control. It has been studied extensively ...in relation to a wide variety of negative outcomes including addiction, obesity, gambling, and so forth. However, we do not have a systematic understanding of when and why people would show a preference for immediate smaller over larger, but delayed rewards. We suggest that delay discounting is goal driven and could therefore be understood by applying the principles of goal pursuit. Across 5 studies we provide empirical evidence to support this proposal. Specifically, we show that (a) people discount a reward to a greater extent if the reward is relevant to their goals; (b) the tendency to discount the rewards as a function of delay is reduced when these goals could be attained through alternative means.
Nanocrystalline ferrites are known to be used in different applications, including industrial wastewater management. For environmental water issues, one of the most widely applied techniques is the ...adsorption of pollutants. The adsorption capacity of Congo red (CR) dye on different MFe2O4 (M = Co2+, Mg2+, Mn2+, Ni2+, and Zn2+) ferrites, synthesized by coprecipitation method, was determined. Specific isotherms and kinetic models were used to characterize the adsorption process. Interesting results were obtained for MgFe2O4 with adsorption capacity ranging from 39% up to 70% dependent on the initial dye concentration. Furthermore, an artificial intelligence model based on neural network was developed in order to model the adsorption rates followed by the generation of 3D adsorption rate models for each type of synthesized ferrite. These models were obtained in order to provide information about the particle‐dye system`s kinetics at various initial CR concentration. Specific techniques were used to characterize the functionalized magnetic particles.
The main steps for obtaining 3D adsorption map.
•GPS data detected rapid deceleration events in a sample of older drivers•Too few 0.75 g deceleration events were found for meaningful analysis.•0.35 g deceleration events were related to declining ...functional abilities.•Several non ability-related factors were related to rapid deceleration events.•0.35 g deceleration events have limited value as a surrogate driving safety measure.
Studies over the past two decades have attempted to document and understand factors related to crashes involving older drivers to develop more effective countermeasures to reduce the frequency and severity of these crashes. Studies in which vehicle acceleration data can be recorded have begun to explore the relationship between rapid deceleration events (RDEs) and functional abilities among older drivers as a surrogate measure of unsafe driving. Recent naturalistic driving studies with older adults have found differing results using different thresholds to define an RDE. The present study examined the relationship among RDE rates, demographics, visual abilities, cognitive abilities, and driving comfort among a large cohort of older drivers, using two definitions of RDEs—longitudinal deceleration of 0.35 g or greater (RDE35) and longitudinal deceleration of 0.75 g or greater (RDE75). The study utilized objective driving, objective functioning, and reported driving comfort data from 2774 participants of the multi-site AAA Longitudinal Research on Aging Drivers (LongROAD) study. RDE rates for each threshold were calculated per 1000 miles driven. Multivariate regression models with backward elimination were developed to examine how outcome measures were related to RDE rates. Too few RDE75 events were found for meaningful analysis. RDE35 rates were significantly associated with several covariates. RDE35 rates were related to declining functional abilities, but many other factors also played a significant role in the rate of RDE35s among older drivers, diminishing the value of using RDE35 rates as a surrogate measure of driving safety. In addition, because the AAA LongROAD sample was relatively healthy and high functioning, other ability-related covariates may also be significantly related to RDE35s but the lack of variance in these measures in the current study prevented these effects from emerging.
•A Fe–Mn–Si alloy was obtained as alloplastic graft material for bone implants.•Fe–Mn–Si alloy degradation rate was preliminary evaluate with SEM and EDAX techniques.•Biochemical, histological, RX ...and CT investigations were done in rats with subcutaneous and tibiae implants.•Fe–Mn–Si alloy assured an ideal compromise between degradation and mechanical integrity during bone regeneration.
Designing substrates having suitable mechanical properties and targeted degradation behavior is the key's development of bio-materials for medical application. In orthopedics, graft material may be used to fill bony defects or to promote bone formation in osseous defects created by trauma or surgical intervention. Incorporation of Si may increase the bioactivity of implant locally, both by enhancing interactions at the graft–host interface and by having a potential endocrine like effect on osteoblasts.
A Fe–Mn–Si alloy was obtained as alloplastic graft materials for bone implants that need long recovery time period. The surface morphology of the resulted specimens was investigated using scanning electrons microscopy (VegaTescan LMH II, SE detector, 30kV), X-ray diffractions (X’Pert equipment) or X-ray dispersive energy analyze (Bruker EDS equipment). This study objective was to evaluate in vivo the mechanisms of degradation and the effects of its implantation over the main metabolic organs. Biochemical, histological, plain X radiography and computed tomography investigations showed good compatibility of the subcutaneous implants in the rat organism. The implantation of the Fe–Mn–Si alloy, in critical size bone (tibiae) defect rat model, did not induced adverse biological reactions and provided temporary mechanical support to the affected bone area. The biodegradation products were hydroxides layers which adhered to the substrate surface. Fe–Mn–Si alloy assured the mechanical integrity in rat tibiae defects during bone regeneration.
Advanced in-vehicle technologies have been proposed as a potential way to keep older adults driving for as long as they can safely do so, by taking into account the common declines in functional ...abilities experienced by older adults. The purpose of this report was to synthesize the knowledge about older drivers and advanced in-vehicle technologies, focusing on three areas: use (how older drivers use these technologies), perception (what they think about the technologies), and outcomes (the safety and/or comfort benefits of the technologies). Twelve technologies were selected for review and grouped into three categories: crash avoidance systems (lane departure warning, curve speed warning, forward collision warning, blind spot warning, parking assistance); in-vehicle information systems (navigation assistance, intelligent speed adaptation); and other systems (adaptive cruise control, automatic crash notification, night vision enhancement, adaptive headlight, voice activated control). A comprehensive and systematic search was conducted for each technology to collect related publications. 271 articles were included into the final review. Research findings for each of the 12 technologies are synthesized in relation to how older adults use and think about the technologies as well as potential benefits. These results are presented separately for each technology. Can advanced in-vehicle technologies help extend the period over which an older adult can drive safely? This report answers this question with an optimistic "yes." Some of the technologies reviewed in this report have been shown to help older drivers avoid crashes, improve the ease and comfort of driving, and travel to places and at times that they might normally avoid.
Biodegradable alloys are very attractive biomaterials. Electrochemical impedance spectroscopy (EIS) and linear potentiodynamic polarization (LPP) techniques were used for the study of the ...electrochemical behavior of uncoated FeMnSi and coated FeMnSi with hydroxyapatite + zirconia (HA-ZrO2) through pulsed laser deposition (PLD) technique. Experiments were carried out using Hank’s balanced salt solution (HBSS). It has been shown that in HBSS the impedance for uncoated FeMnSi was mainly characterized by one capacitive effect, which related to the alloy charge transfer control. The charge transfer resistance increases for HA-ZrO2-coated FeMnSi alloy. The equivalent circuits simulating the electrochemical behavior of both uncoated and HA-ZrO2-coated FeMnSi alloys in HBSS were proposed. From LPP the corrosion resistance was evaluated by means of the zero current potential (ZCP) and corrosion current density ( j c o r r ). The surface morphology of both uncoated and HA-coated FeMnSi alloys in HBSS obtained after LPP was studied using scanning electron microscopy (SEM).
Evidence suggests that older driver safety may be improved by good vehicle maintenance, in-vehicle advanced technologies, and proper vehicle adaptations. This study explored the prevalence of several ...measures of vehicle maintenance and damage among older drivers through inspection of their vehicles. We also investigated the prevalence of in-vehicle technologies and aftermarket adaptations. Vehicle inspections were conducted by trained research staff using an objective, standardized procedure. This procedure, developed by a multidisciplinary team of researchers, was based on a review of inspection checklists used by automobile dealerships and the project team's expertise. The study used baseline data from vehicles of 2988 participants in the multi-site Longitudinal Research on Aging Drivers (LongROAD) study. Among this cohort, vehicles were well maintained, had little damage, and contained a range of advanced technologies but few aftermarket adaptations. Implications of study findings for occupational therapy practice are discussed.
•The paper addresses to a commercial material (P265GH) study in order to combat the effects of H2S containing environments.•After a continuous set of tests realized under H2S environment, results ...were discussed focused on corrosion resistance.•Surface analyze (2 and 3D SEM, EDS, XRD) present an increase of corrosion rate with the exposure to different H2S quantities.
A commercial Fe-C material (P265GH) used for natural gas delivery and transportation systems was analyzed in H2S atmosphere in order to establish the corrosion resistance. In most of the industrial processes for gas purification the corrosion rate is speed up by the presence of sulphur (S) especially as ions (HS-, SO32−) or different species like H2S. The H2S (hydrogen sulphide) is, beside a very toxic compound, a very active element in the acceleration of metallic materials deterioration. For experiments we used a three electrodes cell with Na2SO4+Na2S solution at pH 3 for two different temperatures, room temperature∼25°C (sample 1) and at 60 (sample 2) ±1°C in order to realize EIS (electrochemical impedance spectroscopy) and potentiodynamic polarization. After electro-chemical tests and corrosion resistance characterisation the material surface was analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS).
Interpersonal roadway communication is a vital component of the transportation system. Road users communicate to coordinate movement and increase roadway safety. Future autonomous vehicle research ...needs to account for the role of interpersonal roadway communication. This literature review synthesizes research on interpersonal interaction between drivers, bicyclists, and pedestrians while also directing attention to implications for autonomous and connected vehicle research. Articles were collected from TRID, PsycINFO, Google Scholar, and ScienceDirect using search terms relevant to driving, communication, and vulnerable road users. The synthesis documents that interpersonal communication not only takes place but is also an important and understudied aspect of safe roadway travel. The review also found that road users employ a variety of communication methods that include gestures, facial expressions, and built-in vehicular devices. Comprehension of messages is influenced by several factors including culture, context, and experience. These results shed light on potential issues and challenges of interpersonal communication and the introduction of autonomous vehicles to the roadway.
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