Parametric Study of a Bladeless Fan Geometry: Investigating the Influence of Geometry Parameters on Discharge Ratio and Thrust Force

The innovative bladeless design of the AirMultiplier, patented by Dyson in 2009, has generated significant interest due to its unique approach to air circulation that leverages the Coanda effect. In this study, we present a comprehensive parametric analysis of a simplified bladeless fan geometry, with a specific focus on the discharge ratio and generated thrust force for small to medium radii (5 to 200mm) and a range of flow rates spanning from 1 to 100g/s. In addition to the radii and mass flow rates, this study also addresses the effect of the slit nozzle thickness on the discharge ratio and thrust force of the AirMultiplier. By exploring the influence of this additional parameter, we aim to provide a more complete understanding of the performance characteristics of the geometry and to offer insights that could inform the design and optimization of similar bladeless geometries

Factors associated with the early language development of New Zealand children

Poster PresentationProblem under investigation. This project was undertaken to establish reliable, population-based normative data on the early language development of children growing up in New Zealand (NZ). The project had two aims: (1) to develop nationally representative norms for early vocabulary and grammar based on a NZ adaptation of the MacArthur-Bates Communicative Development Inventory: Words & Sentences (NZ CDI:WS) and (2) to examine their association with demographic, family and child variables. Methods. The target population was parents of monolingual, English-speaking children aged 16-30 months living in NZ. We aimed to collect data on 100 girls and 100 boys at each month of age via a dedicated website (www.kidswords.org), where parents completed an online version of the NZ CDI:WS and a demographic questionnaire. Parents of over 2,600 children participated, representing 87% of our target. 51% of the children were girls; 62% were first-born; 3% were twins and all 16 regions of NZ were represented. Results and conclusion. Children’s expressive vocabulary size ranged from a mean of 67 words (95% CI = 58, 76) at age 16 months to 477 words (95% CI = 453, 502) at 30 months. Age accounted for 47% of the variance in vocabulary size in this age range, while sex, birth order, and whether the child was a twin accounted for 3% additional variance. Similarly, age accounted for 42% of the variance in grammatical complexity scores (CDI section E), with the same factors accounting for 1.6% additional variance. Vocabulary size and grammatical complexity scores were highly correlated (r = .85; 95% CI = .84, 1.00). Percentiles for vocabulary size will be presented and cross-linguistic comparisons will be made between the NZ data and CDI data from other countries. Further uses of the data collected from this project will be discussed

Sustained effects of an early childhood language and literacy intervention through second grade: Longitudinal findings of the SPELL trial in Denmark

Predictive relations between language and literacy skills during the preschool years and children’s future reading achievement are well-documented, leading to development and evaluation of preschool interventions targeting early skill development. Although educational researchers have developed and found some positive short- and mid-term effects of language and literacy intervention supplements implemented in early childhood education (ECE) settings, fade-out is a concern. Most studies have targeted children experiencing risk, rather than a more representative sample. Additionally, there are very few studies of long-term intervention effects, and heterogeneity of long-term effects has not been well described. In the present study, we build on initial reports of one of the largest studies of a language and literacy intervention supplement, the SPELL randomized controlled trial implemented as part of the universal ECE system in Denmark. SPELL was delivered to an unselected sample of children at 3–5 years of age (n = 7,076). Results of the base intervention (SPELL) and two enhanced versions featuring extended professional development for teachers (SPELL+PD) or an add-on home-based program for parents (SPELL+HOME) showed short-term effects for literacy outcomes for all children for all SPELL conditions compared to business as usual (BAU). In this follow-up study, we utilized follow-up assessments of 2,700 SPELL 4-5-year-old participants with national reading tests in second grade. The main analyses based on the whole sample showed no significant differences in reading scores in second grade for those in any of the three SPELL conditions relative to the BAU condition. However, moderation analyses demonstrated heterogeneity in intervention effects with children whose mothers had low-mid education showing sustained and mostly large-sized effects. Other risk factors, including income and immigrant background, and condition interacted with at least one outcome variables. These findings suggest that at-risk children in some cases derive long-term benefits from early language and literacy intervention enhancing learning opportunities in ECE settings.</jats:p