Quantitative evaluation of optical lock-in and pulsed thermography for aluminum foam material

AbstractIn this article, quantitative evaluation of optical thermographic techniques relative to the non-destructive inspection of aluminum foam material is studied. For this purpose, a set of aluminum foam specimens with flat-bottom holes (FBH) was inspected by both optical lock-in thermography (LT) and pulsed thermography (PT). Probability of detection (PoD) analysis, as a quantitative method to estimate the capability and reliability of a particular inspection technique, was studied and compared for both optical LT and PT inspection results

Comparative study of microlaser excitation thermography and microultrasonic excitation thermography for submillimeter porosity in carbon fiber reinforced polymer composites

Stitching is used to reduce incomplete infusion of T-joint core (dry-core) and reinforce T-joint structure. However, it may cause new types of flaws, especially submillimeter flaws. Thermographic approaches including microvibrothermography, microlaser line thermography, and microlaser spot thermography on the basis of pulsed and lock-in techniques were proposed. These techniques are used to detect the submillimeter porosities in a stitched T-joint carbon fiber reinforced polymer composite specimen. X-ray microcomputed tomography was used to validate the thermographic results. Finally an experimental comparison of microlaser excitation thermography and microultrasonic excitation thermography was conducte

Extended Haplotypes in the Growth Hormone Releasing Hormone Receptor Gene (GHRHR) Are Associated with Normal Variation in Height

Mutations in the gene for growth hormone releasing hormone receptor (GHRHR) cause isolated growth hormone deficiency (IGHD) but this gene has not been found to affect normal variation in height. We performed a whole genome linkage analysis for height in a population from northern Sweden and identified a region on chromosome 7 with a lod-score of 4.7. The GHRHR gene is located in this region and typing of tagSNPs identified a haplotype that is associated with height (p = 0.00077) in the original study population. Analysis of a sample from an independent population from the most northern part of Sweden also showed an association with height (p = 0.0039) but with another haplotype in the GHRHR gene. Both haplotypes span the 3′ part of the GHRHR gene, including the region in which most of the mutations in IGHD have been located. The effect size of these haplotypes are larger than that of any gene previously associated with height, which indicates that GHRHR might be one of the most important genes so far identified affecting normal variation in human height

Automated segmentation of ultrasonic volumetricdata of composite materials

International audienceManual ultrasonic testing is frequently applied to inspect the quality of carbon fibre-reinforced polymer composites(CFRP), especially in the aerospace industry. There is an immediate requirement to replace manual ultrasonic testing anddata evaluation with an automated system. A part of the solution is provided via automated acquisition of ultrasounddata. The second part to be solved is the analysis of the enormous amount of data generated. The objective of thiscontribution is to propose a method that can provide an automated interpretation of data. The proposed method istested on two CFRP samples with artificial defects of different sizes, depths and shapes

App-based mathematical intervention for youth with intellectual disabilities: a randomised controlled trial

The purpose of the study was to evaluate whether students with intellectual disabilities (ID) can improve their arithmetic skills by participating in an arithmetic intervention programme, theoretically founded on explicit instruction (EI) and administered via an application developed for tablet computers. The intervention study used a randomised controlled trial design (RCT) (n = 30, aged 10-16, 13 females) and lasted for up to 12 weeks. The results show that the intervention group significantly improved in arithmetic fact fluency compared to the controls and the effects remained six months after the intervention. The effects were larger for subtraction than for addition, and this difference remained six months later. These results suggest that mathematics applications based on explicit instruction can be an effective way of teaching arithmetic facts to youth with mild ID