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The purpose of this paper is to present a model that can be used to simulate the photopolymerization process in micro‐stereolithography (SL) in order to predict the shape of the cured parts. SL is an additive manufacturing process in which liquid photopolymer resin is cross‐linked and converted to solid with a UV laser light source. Traditional models of SL processes do not consider the complex chemical reactions and species transport occurring during photopolymerization and, hence, are incapable of accurately predicting resin curing behavior. The model presented in this paper attempts to bridge this knowledge gap.

The chemical reactions involved in the photopolymerization of acrylate‐based monomers were modeled as ordinary differential equations (ODE). This model incorporated the effect of oxygen inhibition and diffusion on the polymerization reaction. The model was simulated in COMSOL and verified with experiments conducted on a mask‐based micro‐SL system. Parametric studies were conducted to investigate the possibilities to improve the accuracy of the model for predicting the edge curvature.

The proposed model predicts well the effect of oxygen inhibition and diffusion on photopolymerization, and the model accurately predicts the cured part height when compared to experiments conducted on a mask‐based SL system. The simulated results also show the characteristic edge curvature as seen in experiments.

A triacrylate monomer was used in the experiments conducted, so results may be limited to acrylate monomers. Shrinkage was not considered when comparing cured part shapes to those predicted using COMSOL.

This paper presents a unique and a pioneering approach towards modeling of the photopolymerization reaction in micro‐SL process. This research furthers the development of patent pending film micro‐SL process which can be used for fabrication of custom micro‐optical components.

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).

To cope with the complexity of modern retail stores and personal time constraints, shoppers must be selective in processing information. During a typical shopping trip, they visit only a fraction of a store’s departments and categories, examine a small subset of the available products, and often make selections in just a few seconds. New research techniques can help marketers understand how customers allocate their attention and assess the impact of in-store factors on shopper behavior. This chapter summarizes studies using observational research, virtual reality simulations, and eye tracking to identify the drivers of shopper attention, product engagement, and purchase conversion. These include shopper goals; product assortment, package appearance, price, and merchandising; shelf space allocation, organization, and adjacencies; and salesperson interaction. The research reveals that small changes in a product’s appearance and presentation can have a powerful impact on consideration and choice.

This chapter describes the Bornlearning ^® Academy (BLA), a school-based family engagement program predicated on the notion that families come to the table with knowledge and skills and can support children’s learning by building on what they are already doing. It takes place in a school building within the families’ school district, and it is a six-workshop series that utilizes materials available for free at bornlearning.org, a United Way Worldwide public engagement campaign. The goal of the BLA is to increase parents’/caregivers’ understanding of their role in the education process of their children and to facilitate familiarization and establishment of positive experiences with the school personnel and the school district for the children and their families. Survey data demonstrated that parents/caregivers from a range of backgrounds enjoyed and learned from various BLA workshops. Gains on content questions indicated the BLA attendees learned, and responses indicated that attendees both intended to use what they learned at the workshops in their own interactions with their children and actually followed through on those intentions.

Current issues of Publishers' Weekly are reporting serious shortages of paper, binders board, cloth, and other essential book manufacturing materials. Let us assure you these shortages are very real and quite severe.

Children experience trauma more often than many early childhood educators realize. As many as 26% of children experience multiple trauma events such as abuse, neglect, parental substance abuse, parental incarceration, and so forth. Trauma impacts brain development in many negative ways that may have serious consequences on the child’s ability to learn, grow socially and emotionally, and develop physically. These brain changes also change how the child will play in the early childhood classroom, and information is given to help recognize the signs of trauma in children. The early childhood educator can make trauma-sensitive modifications in the classroom to assist the traumatized child’s ability to play out the problem. School counselors can be a resource for assisting early childhood teachers when working with traumatized children. A brief description of the importance of play therapy as a developmentally appropriate method to help traumatized young children is provided.