К численному решению задач о деформации анизотропных пластин с отверстием

Представлен подход к расчету напряженно-деформированного состояния пластин с отверстием, основанный на численной параметризации двусвязной области, сведении исходной нелинейной краевой задачи к последовательности линейных двухмерных и интегрировании последних устойчивым численным методом. Исследуется влияние формы и месторасположения отверстия на напряженно-деформированное состояние квадратной пластины.Представлено підхід до розрахунку напружено-деформованого стану пластин, що послаблені отвором. Підхід базується на числовій параметризації двозв’язної області, зведенні вихідної нелінійної задачі до послідовності лінійних двомірних та останніх до одномірних, інтегрування яких проводиться стійким числовим методом. Досліджується вплив форми та місцезнаходження отвору на напружено-деформований стан квадратної пластини.The study presents an approach to stressed-state analysis of plates with apertures which is based on the numerical parameterization of a doubly-connected area, reduction of the initial nonlinear boundary-value problem to a sequence of linear two-dimensional problems and integrating the latter by the stable numerical method. The effect of form and place of an aperture on stressed state of a square plate has been analyzed

Comparing consumer perceptions of appliances' electricity use to appliances' actual direct-metered consumption

Many strategies for reducing residential energy consumption—including product labelling programs, subsidies for the purchase of efficient devices, behavioral programs that encourage efficient energy use, and others—rely on building owners and end users to make informed investment and operational decisions. These strategies may be ineffective if consumers are unaware of how much electricity is used by different devices in their homes and buildings. This study therefore compares consumers' perceptions of their appliances' electricity use to these appliances' actual direct-metered electricity consumption. Using an online survey, 118 homeowners from Austin, Texas were asked to estimate the energy consumption of six household devices which were monitored in the participants' homes. Homeowners were randomly assigned to assess their appliance-specific electricity use in terms of energy units (kWh/month) or energy cost units ($/month) for an average summer month. Consistent with previous studies, participants overestimated the energy consumed by their low energy consuming devices and slightly underestimated that of their most energy-consuming device. Results also showed that responses of the experimental groups estimating their consumption in energy units and energy cost units were similar, the accuracy of the two groups' perceptions was similar, and levels of confidence in the two groups were similar. These results suggest that targeted information campaigns focused on air conditioning energy consumption and device power reduction opportunities could improve consumer decision-making to save energy and reduce demand

Decision-Making Competence: More Than Intelligence?

Decision-making competence refers to the ability to make better decisions, as defined by decision-making principles posited by models of rational choice. Historically, psychological research on decision-making has examined how well people follow these principles under carefully manipulated experimental conditions. When individual differences received attention, researchers often assumed that individuals with higher fluid intelligence would perform better. Here, we describe the development and validation of individual-differences measures of decision-making competence. Emerging findings suggest that decision-making competence may tap not only into fluid intelligence but also into motivation, emotion regulation, and experience (or crystallized intelligence). Although fluid intelligence tends to decline with age, older adults may be able to maintain decision-making competence by leveraging age-related improvements in these other skills. We discuss implications for interventions and future research

Photoinduced Halogen-Atom Transfer by N-Heterocyclic Carbene-Ligated Boryl Radicals for C(sp³)-C(sp³) Bond Formation

Herein, we present a comprehensive study on the use of N-heterocyclic carbene (NHC)-ligated boryl radicals to enable C(sp3)–C(sp3) bond formation under visible-light irradiation via Halogen-Atom Transfer (XAT). The methodology relies on the use of an acridinium dye to generate the boron-centered radicals from the corresponding NHC-ligated boranes via single-electron transfer (SET) and deprotonation. These boryl radicals subsequently engage with alkyl halides in an XAT step, delivering the desired nucleophilic alkyl radicals. The present XAT strategy is very mild and accommodates a broad scope of alkyl halides, including medicinally relevant compounds and biologically active molecules. The key role of NHC-ligated boryl radicals in the operative reaction mechanism has been elucidated through a combination of experimental, spectroscopic, and computational studies. This methodology stands as a significant advancement in the chemistry of NHC-ligated boryl radicals, which had long been restricted to radical reductions, enabling C–C bond formation under visible-light photoredox conditions

Assessment of observer performance in a subjective scoring system: visual classification of the gait of cows

As with any measurement procedure, the performance of a subjective classification procedure must be evaluated. Observers have to be trained and their performance has to be assessed, preferably on a regular basis, to guarantee sufficient consistency and accuracy of classification results. The current paper is a study of observer performance where observers were asked to classify the gait of cows from video recordings. Gait was classified in nine ordered categories (ranging from 1 = normal gait to 9 = severely abnormal gait) and also as a continuous fraction by putting a mark on a paper strip (the left end corresponding to 0 = normal gait and the right end to I = severely abnormal gait). The use of statistical models and methodology for analysis of these visual scores is demonstrated and discussed. Observers were assessed by comparing their classification results with the results of an expert. Models and methodology take proper account of typical features of the data, i.e. the fact that data are discrete scores or continuous scores with an upper and lower bound, the variance heterogeneity and non-linearity of model terms that arises from this, and the dependence between repeated classifications of videos of the same cow. Results of the analyses are summarized in simple tables and plots. These are useful tools to indicate possible flaws in judgement of an observer, that may be corrected by further training. When a high standard is developed, which usually takes the form of the opinion of one or more experts, this methodology can be applied prior to any experiment where responses are ordered subjective scores

Long-Time Behavior of Velocity Autocorrelation Function for Interacting Particles in a Two-Dimensional Disordered System

The long-time behavior of the velocity autocorrelation function (VACF) is investigated by the molecular dynamics simulation of a two-dimensional system which has both a many-body interaction and a random potential. With strengthening the random potential by increasing the density of impurities, a crossover behavior of the VACF is observed from a positive tail, which is proportional to t^{-1}, to a negative tail, proportional to -t^{-2}. The latter tail exists even when the density of particles is the same order as the density of impurities. The behavior of the VACF in a nonequilibrium steady state is also studied. In the linear response regime the behavior is similar to that in the equilibrium state, whereas it changes drastically in the nonlinear response regime.Comment: 12 pages, 5 figure

Thermocapillary actuation of liquid flow on chemically patterned surfaces

We have investigated the thermocapillary flow of a Newtonian liquid on hydrophilic microstripes which are lithographically defined on a hydrophobic surface. The speed of the microstreams is studied as a function of the stripe width w, the applied thermal gradient |dT/dx| and the liquid volume V deposited on a connecting reservoir pad. Numerical solutions of the flow speed as a function of downstream position show excellent agreement with experiment. The only adjustable parameter is the inlet film height, which is controlled by the ratio of the reservoir pressure to the shear stress applied to the liquid stream. In the limiting cases where this ratio is either much smaller or much larger than unity, the rivulet speed shows a power law dependency on w, |dT/dx| and V. In this study we demonstrate that thermocapillary driven flow on chemically patterned surfaces can provide an elegant and tunable method for the transport of ultrasmall liquid volumes in emerging microfluidic technologies

Individual-level factors predicting consumer financial behavior at a time of high pressure

Understanding the individual-level factors relating to consumer financial behaviors during periods of distinct pressure to spend may provide new insights as to the particular barriers people face in maintaining better control over their finances. Using Christmas as a focal example of a financially and psychologically pressured time, we collected survey data (N= 294) in the post-Christmas 2013 period, and investigated the extent to which levels of reported spending and borrowing in relation to Christmas could be predicted by sociodemographics, money management behaviors, and psychological factors such as coping style, locus of control, materialism, and spendthrift tendencies. A separate analysis examined the kinds of factors relating more specifically to money management behaviors. Spending was predicted by factors including external locus of control and spendthrift tendency. Emotional coping and denial coping predicted borrowing behavior, as did external locus of control. Money management behaviors predicted who borrowed, but were not related to amount borrowed. Spendthrift tendencies and materialistic values were predictive of less active money management. Our findings suggest that interventions to improve financial decision making might prove more effective if increased emphasis is placed on psychological issues such as developing coping skills and buffering agency