Intelligence quotient

Summary

An intelligence quotient (IQ) is a total score derived from a set of standardised tests or subtests designed to assess human intelligence. The abbreviation "IQ" was coined by the psychologist William Stern for the German term Intelligenzquotient, his term for a scoring method for intelligence tests at University of Breslau he advocated in a 1912 book. Historically, IQ was a score obtained by dividing a person's mental age score, obtained by administering an intelligence test, by the person's chronological age, both expressed in terms of years and months. The resulting fraction (quotient) was multiplied by 100 to obtain the IQ score. For modern IQ tests, the raw score is transformed to a normal distribution with mean 100 and standard deviation 15. This results in approximately two-thirds of the population scoring between IQ 85 and IQ 115 and about 2.5 percent each above 130 and below 70. Scores from intelligence tests are

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Prenatal experience and transgenerational influences are increasingly recognized as critical for defining the socio-emotional system, through the development of social competences and of their underlying neural circuitries. Here, we used an established rat model of social stress resulting from male partner aggression induced by peripubertal (P28-42) exposure to unpredictable fearful experiences. Using this model, we aimed to first, characterize adult emotionality in terms of the breadth of the socio-emotional symptoms and second, to determine the relative impact of prenatal vs postnatal influences. For this purpose, male offspring of pairs comprising a control or a peripubertally stressed male were cross-fostered at birth and tested at adulthood on a series of socio-emotional tests. In the offspring of peripubertally stressed males, the expected antisocial phenotype was observed, as manifested by increased aggression towards a female partner and a threatening intruder, accompanied by lower sociability. This negative outcome was yet accompanied by better social memory as well as enhanced active coping, based on more swimming and longer latency to immobility in the forced swim test, and less immobility in the shock probe test. Furthermore, the cross-fostering manipulation revealed that these adult behaviors were largely influenced by the post- but not the prenatal environment, an observation contrasting with both pre- and postnatal effects on attacks during juvenile play behavior. Adult aggression, other active coping behaviors, and social memory were determined by the predominance at this developmental stage of postnatal over prenatal influences. Together, our data highlight the relative persistence of early life influences.

2021

Speaker verification in score-ageing-quality classification space

Andrzej Drygajlo, Finnian Paul Kelly

A challenge in automatic speaker verification is to create a system that is robust to the effects of vocal ageing. To observe the ageing effect, a speaker's voice must be analysed over a period of time, over which, variation in the quality of the voice samples is likely to be encountered. Thus, in dealing with the ageing problem, the related issue of quality must also be addressed. We present a solution to speaker verification across ageing by using a stacked classifier framework to combine ageing and quality information with the scores of a baseline classifier. In tandem, the Trinity College Dublin Speaker Ageing database of 18 speakers, each covering a 30-60 year time range, is presented. An evaluation of a baseline Gaussian Mixture Model Universal Background Model (GMM-UBM) system using this database demonstrates a progressive degradation in genuine speaker verification scores as ageing progresses. Consequently, applying a conventional threshold, determined using scores at the time of enrolment, results in poor long-term performance. The influence of quality on verification scores is investigated via a number of quality measures. Alongside established signal-based measures, a new model-based measure, Wnorm, is proposed, and its utility is demonstrated on the CSLU database. Combining ageing information with quality measures and the scores from the GMM-UBM system, a verification decision boundary is created in score-ageing-quality space. The best performance is achieved by using scores and ageing in conjunction with the new Wnorm quality measure, reducing verification error by 45% relative to the baseline. This work represents the first comprehensive analysis of speaker verification on a longitudinal speaker database and successfully addresses the associated variability from ageing and quality arte-facts. (C) 2013 Elsevier Ltd. All rights reserved.

Academic Press Ltd- Elsevier Science Ltd2013

THE RIGHT WAY TO CHARACTERIZE ADHESION OF POLYMERS IN PV MODULES

Valentin Chapuis, Vincent Trachsel

It is widely accepted that adherence (which reports to what is measured when performing an adhesion test) of the encapsulant to the main substrates of the module plays a key role in the long term reliability of the PV module [1,2]. Consequently, adherence is commonly measured and used to assess or compare encapsulant compatibility with a given substrate. The most common procedures used in the PV field to characterize adhesion between a polymer film and a substrate are the so called peeling test, lap shear and compressive shear tests. Here we use a compressive shear setup to characterize the adherence of Poly Vinyl Butyral (PVB) and Polyethylene-covinyl acetate (EVA) to glass before and after degradation in damp-heat (DH) conditions (85°C, 85%RH). The adherence metrics that can be derived from a Compressive Shear Test (CST) are presented and discussed. We show that a single metric is not sufficient to characterize adherence and that a set of at least two indicators including the peak shear stress and the viscous dissipation should be used. Using this set it is found that the interface PVB/Glass is more affected by the degradation than the EVA/Glass interface.

2011