Bulletin of NTU "KhPI". Series: Problems of Electrical Machines and Apparatus Perfection. The Theory and Practice / Вісник Національного технічного університету "ХПІ". Серія: Проблеми удосконалювання електричних машин і апаратів. Теорія і практика
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Not two monolinguals in one mind: Bilingual logical representations are shared despite cross-linguistic differences
No full textDo bilinguals share logical representations in processing both languages, even if those languages differ in their scope-taking biases? We tested cross-linguistic priming in the comprehension of scopally ambiguous "all...not" sentences in Estonian-English bilinguals. These sentences are interpreted differently in English and Estonian. Across three sentence-picture matching experiments, we observed that bilingual logical representations can be primed both within- and between-languages. Moreover, a control experiment ruled out an explanation in terms of visual priming. These findings indicate that bilinguals use shared logical representations in processing both languages, which do not specify language-specific biases in scope assignment. Additionally, our results showed that Estonian-English bilinguals learn L2-specific scope assignment biases, and that they encounter cross-linguistic influence in the construction logical representations. This latter finding suggests that bilinguals rely on integrated representations of implicit knowledge about scope assignment
Can you see an emotion?: Emotional evaluation of contextless visual stimuli in Virtual Reality
No full textPrevious studies support the existence of objective emotional visual cues. For
instance, red and blue are usually associated with high and low arousal, respectively. A similar phenomenon has been observed with other colors, as well as textures, shapes, and motion patterns. Yet, it is not clear to which extent this phenomenon can be extrapolated to Virtual Reality (VR) stimuli. Therefore, this manuscript presents an experiment where five virtual environments were evaluated by 21 participants in terms of valence and arousal. The design of the virtual environments was informed by evidence found in previous studies. Each environment represents one of the four quadrants of the Circumplex Model of Affect, plus a neutral environment. The results suggest that the emotions associated with the virtual environments are consistent with the evidence used to inform the design
process. Individual differences across participants do not seem to influence the evaluation of the visual cues
Why People Think that Higher-Paid Workers Make Higher-Quality Products
No full textInformation about workers’ wages is publicly available through various sources (e.g., Glassdoor, SEC statements). How does this wage information affect the perceived quality of the products made by these workers? Across eight experiments with participants from the U.S., Britain, and France, we find that people expect and perceive products to be of higher quality when made by well-paid workers—both in comparison to products made by lower-paid workers and to those from companies where wage information is unknown. These perceptions, in turn, increase consumers’ likelihood of choosing these products and their willingness to pay a premium. This effect is driven by the belief that well-paid workers are more satisfied, which leads to higher-quality output. Our findings contribute to research on the determinants of value and quality expectations, as well as lay theories of product quality. They also offer practical implications for the communication, use, and regulation of worker pay information
Blinded versus unblinded review: A field study comparing the equity of peer review
No full textBlinded review is often proposed as a solution to inequities in merit-based evaluations. We tested this claim in a high-stakes field experiment comparing single-blind review (reviewer identities withheld) and double-blind review (reviewer and author identities withheld) for 530 academic conference submissions. On reliability, both processes showed moderate reliability, leading to only 40\% overlap among top-rated submissions. This low overlap indicates that differences between review systems partly stem from noise in the review system. In terms of fairness, our analysis indicates that single-blind reviews favored more senior coauthors and first authors who were Ph.D. students or research scientists, while disfavoring Asian (vs. White) first authors. Meanwhile, male first authors received slightly higher ratings in both conditions (especially under double-blind), but the greater the proportion of male coauthors, the lower the review ratings were under double-blind (vs. single-blind). On validity, we find that for submissions accepted and presented as a talk, neither review ratings nor author characteristics predicted talk quality, number of questions, or attendance. However, review ratings from both systems similarly predicted judged poster presentation quality (for a subset of submissions) and eventual publication (for all submissions). These findings highlight limitations in both single- and double-blind approaches. Double-blind review is not a cure-all for inequities that might arise via single-blind. Yet, including author identities does not appear to enhance reliability or validity enough to justify the risks this information poses in potentially advantaging a particular individual or group
Особливості визначення часткових ємностей ізоляції трьожильних силових кабелів із застосуван-ням прямих вимірювань
Full text linkThe article is dedicated to the analysis of impact of the additional component of parasitic inductance of measuring circuit, which exists due to the necessity of applying the additional conductor in order to remove the influence of parasitic capacitances of the analyzed layer of insulation, on the results of determining the partial capacitances of insulation of three-core power cables in a common metal sheath by applying the direct measurements. It was experimentally shown that the existence of an additional component of parasitic inductance leads to resonance phenomena in the measuring circuit and, as a result, to the increasing of the results of the direct measurements of partial capacitances with the increasing of frequency, which contradicts the frequency dependence of dielectric permeability of paper insulation in the considered frequency range. Diagrams of connection of immittance meters with 3 terminals for direct measurements of partial capacitances of insulation in three-core power cables in a common metal sheath are presented. For the tested sample of power cable it was shows that at a frequency of 10 kHz, a high level of agreement is observed between the results of determining partial capacitances obtained by using the methods which require the applying of immittance meters with 2 and 3 terminals. This agreement is evidence that for the tested power cable design at a frequency of 10 kHz, the additional component of the inductance of the measurement circuit does not affect the results of measurements.Стаття присвячена дослідженню впливу додаткової складової паразитної індуктивності схеми вимірювання, що зумовлена необхідністю застосування додаткового провідника для усунення впливу паразитних ємностей досліджуваного шару ізоляції, на результати визначення часткових ємностей ізоляції трьохжильних силових кабелів в спільній металевій оболонці із застосуванням прямих вимірювань. Експериментальним шляхом показано, що наявність додаткової складової паразитної індуктивності призводить до резонансних явищ в схемі вимірювання та, як наслідок, до збільшення результатів прямих вимірювань часткових ємностей із зростанням частоти, що суперечить частотній залежності діелектричної проникності паперової ізоляції в розглянутому частотному діапазоні. Наведено схеми підключення вимірювачів імітансу із 3 клемами для прямих вимірювань часткових ємностей ізоляції трьохжильних силових кабелів в спільній металевій оболонці
Самоадаптивна конденсаторна ізоляція для приглушення часткових розрядів у високовольтних системах: квантово-польовий підхід на основі RTV+ZNO-нанофольга
Full text linkAn electrophysically rigorous rationale is presented for reducing the intensity of partial discharges (PD) in capacitor-type insulation of current transformers in the 110-330 kV voltage class by integrating a thin semiconductive layer based on an RTV/epoxy binder filled with ZnO, applied along the edges of perforated aluminum collars and foil electrodes. The mechanisms of edge electric-field control ∇E are considered via a distributed RC line with layer sheet resistance Rs (ohms per square) and interelectrode capacitance ε0ε/hd, as well as via the nonlinear conductivity of ZnO grain boundaries (Schottky barrier, Poole-Frenkel effect, tunneling transport). It is shown that proper selection of Rs (50 Hz) = 108-109 Ω/sq, coating thickness δ = 0.30-0.70 mm, and bonding length lsp provides exponential attenuation of edge field strength and an increase in the inception voltage of surface PD in accordance with IEC 60270 methodology and the test prescriptions of IEC 60060-1; unified assumptions are given for PD modeling by the equivalent Ca-Cb-Cc circuit, and the results of numerical experiments (Matlab/Simulink) are reported to be consistent with IEEE Std 1434 (PD measurement). It is noted that, due to the historical evolution of trap states in ZnO and relaxation of the orientational polarization of RTV, stabilizing electrical aging occurs: upon repetition of 103-106 PD impulses, the local energy Wpd and the peak field in the edge zone decrease by 35-50 % without violating limiting values of leakage current and tanδ(f).Подано електрофізично коректне обґрунтування зниження інтенсивності часткових розрядів (ЧР) у конденсаторній ізоляції трансформаторів струму класу напруги 110-330 кВ шляхом інтеграції тонкого напівпровідного шару на основі RTV/епоксидного зв’язника з наповнювачем ZnO, нанесеного вздовж кромок перфорованих алюмінієвих манжет та фольгових обкладок. Розглянуто механізми керування крайовим електричним полем ∇E через розподілену RC-лінію з параметрами листового опору шару Rs (Ом/кв) та міжелектродної ємності ε0ε/hd, а також через нелінійну провідність межзернових границь ZnO (бар’єр Шотткі, ефект Пуля-Френкеля, тунельний перенос). Показано, що коректний добір Rs(50 Гц)=108-109 Ом/кв, товщини покриття δ=0,30-0,70 мм і довжини проклейки lsp забезпечує експоненційне затухання крайової напруженості та підвищення напруги виникнення поверхневих ЧР відповідно до методики IEC 60270 та випробувальних приписів IEC 60060-1; наведено уніфіковані припущення для моделювання ЧР за еквівалентною схемою Ca-Cb-Cc і результати чисельних експериментів (Matlab/Simulink), узгоджені з IEEE Std 1434 (PD measurement). Зазначено, що внаслідок історичної еволюції станів пасток у ZnO та релаксації орієнтаційної поляризації RTV відбувається стабілізувальне електричне старіння: при повторенні 103-106 імпульсів ЧР локальна енергія Wpd і пікова напруженість у зоні кромки зменшуються на 35-50% без порушення граничних значень струму витоку і tgδ(f)
Higher Trait Working Memory Capacity May Benefit Standardized Test Performance under Race Related Stereotype Threat
No full textStereotype Threat (ST) occurs when individuals primed with negative stereotypes underperform relative to a control group. Activating ST increases anxiety and worries about being negatively perceived, also introducing mental distraction that negatively impacts performance. We consider racial/ethnic ST effects on standardized test performance (SDTP) on the verbal and quantitative reasoning sections of the Graduate Record Exam (GRE). Across two experiments, Working Memory Capacity (WMC) is investigated as a mediator and/or moderator of ST for race/ethnicity (Experiment 1, final n = 447, 19% Black, 81% White, 59% Female and for Experiment 2, n = 166, 41% Black, 59% White, 73% Female). We find a lack of strong evidence for the classic ST effect of a race by condition interaction. However, we show evidence that for Black students, higher trait WMC moderates racial/ethnic ST such that higher WMC is associated with higher scores on standardized tests under conditions of race related ST. Our findings suggest the importance of higher WMC for racial minority students in remaining mentally resilient and maintaining performance during ST. Future work should address diversity and inclusion concerns regarding research on ST effects for racial/ethnic minorities, include more work examining racial/ethnic ST based on replication issues and statistical power, as well as more examination of the importance of WMC for performance under racial/ethnic ST. Future work should also consider the roles of protective factors, such as mindfulness and self-regulation practices in the context of racial/ethnic ST as WMC and SDTP have been shown to generally improve through implementing these practices
The Value of Names - Civil Society, Information, and Governing Multinationals
No full textCan markets discipline socially costly misbehavior abroad? We explore the market penalty associated with major human rights violations—specifically, the assassination of mining activists, a context where formal legal recourse is rare and events often do not involve counterparties. We show that firms featured in media coverage of these incidents experience significant, negative abnormal stock returns. Whereas reactions to corporate misconduct may be muted or transitory, we find that the market responses are both substantial and persistent, with a median 10-day loss exceeding USD 100 million. Since formal legal sanction is exceedingly rare, we consider the market costs behind these movements. We highlight three mechanisms consistent with a reputational channel: (1) Media attention magnifies the market response. (2) Information-sensitive institutional investors systematically divest following assassination events. (3) Events reduce future trade, leading to a 32% decline in new contracts with counterparties. Despite these costs, events persist. We find that assassinations increase with dependence on mining royalties, suggesting that local rents sustain conflict despite market pressure. Thus, reputational sanctions may be significant—even in weakly institutionalized settings—yet may not fully deter misbehavior when local and global incentives diverge
Aversive Responses to Stereotypic STEM Images Predicts Women’s Long–Term STEM Memories and Underperformance in Math
No full textSocial identity threat (SIT) is a situational stressor that increases arousal and negative affect, biases memory encoding towards domain-specific negative affect, and impairs performance when women are outnumbered by men. One consequence of these effects could be that women develop learned aversions towards stigmatized STEM domains. Four studies tested whether stereotypic STEM images (STEMIs) prompt aversive-like responses that predict SIT-like outcomes, including underperformance in SIT contexts and more negative SIT-oriented memories over time. Using a dot-probe paradigm, Study 1 found that only SIT women exhibited greater arousal responses to STEMIs compared to stereotypic non-STEM images (NonSTEMIs), perceived STEMIs as more negatively arousing compared to men, and underperformed; men in this context showed a similar arousal response to STEMIs and NonSTEMIs and performed better. Study 2 replicated this effect among women STEM majors and linked aversive responses to more negative affect laden memories for the STEM lab experience five weeks later. Using EEG, Study 3 found that enhanced processing of STEMIs presented during an attentional blink task (indexed via increased communication between occipital and prefrontal cortical regions) predicted underperformance on a math test among SIT women but marginally better performance among men. Study 4 mitigated SIT underperformance effects among women utilizing a dot-probe training paradigm that blunted arousal responses to STEMIs; instructing men to attend to STEMIs facilitated their performance. STEM aversions may thus facilitate SIT-like effects, possibly defining what the “threat” in SIT is, however, blunting aversions can attenuate these effects when women work alongside men in STEM performance situations
1/f Fluctuations on a Chain of Causal Relationships (Ⅰ); Formalization
No full textIn order to discuss the 1⁄f problem, the statistics of the branching process of a particle in a multiplicative medium is developed by taking into account random particle immigration. The probability distribution function of the number of particles found in the medium at any fixed time and/or of particles detected in a time interval is obtained in closed form. These results are applied to the case where exactly two particles are produced by branching