A study of explanatory factors

Koot, J.M. [Promotor]Loeber, R. [Promotor]Hipwell, A. [Copromotor

Expanding Kindergarten Students’ Understanding of Family Types

Today, family dynamics are drastically changing. Many children may not recognize the variances of family members and styles. To educate young students, I formulated a 3-session lesson to address different family dynamics with Kindergarten students at Dual Language Academy. My goal is to form an understanding among the students of diversity and inclusion within families

Investment Casting of Thin Sections in Superalloys

The ability to create highly complex components through investment casting of superalloys is extremely important for producing turbine blades. Often, the sharp corners in the castings will not fill completely, resulting in unintentionally rounded corner which must be machined to achieve the final, required dimensions. By better understanding the interactions between the liquid metal and the mold, the as-cast shape can be improved, producing higher quality castings. A 2D, analytical model was developed to predict the ability to fill a V-shaped channel lined with cylindrical particles. The model was found to accurately predict the ability to fill a channel based on the contact angle, particle radius, corner angle, and head height. The predictions from the analytical model were verified using small-scale experiments and the 3D surface modeling software, Surface Evolver. The head height and contact angle were found to have the biggest impact on the ability to fill, while the particle radius has a smaller effect on filling. Sessile drop experiments with pure nickel droplets on alumina substrates of varying roughness, similar to those found in industrial investment casting, in flowing argon found that the measured, or effective, contact angle can be altered by approximately 20° based on the substrate surface roughness, with surfaces that are more rough having higher effective contact angles. There is little benefit to decreasing the surface roughness below a -325 mesh particle size (≤44 μm), but increasing the surface roughness above a -325 mesh will negatively impact corner filling. The 2D analytical model was used to design a casting to measure the ability to fill fine features similar to those in turbine blades as a function of head height, feature size, and corner half-angle. The casting was produced from MAR M247 using conventional investment casting processes. The casting shows a dependence of the ability to fill sharp corners on head height, while the mold and wax pattern do not. This proves that the rounded corners found in castings can be due to the inability to fill the sharp corners in the mold

Accurate pedestrian localization in overhead depth images via Height-Augmented HOG

We tackle the challenge of reliably and automatically localizing pedestrians in real-life conditions through overhead depth imaging at unprecedented high-density conditions. Leveraging upon a combination of Histogram of Oriented Gradients-like feature descriptors, neural networks, data augmentation and custom data annotation strategies, this work contributes a robust and scalable machine learning-based localization algorithm, which delivers near-human localization performance in real-time, even with local pedestrian density of about 3 ped/m2, a case in which most stateof- the art algorithms degrade significantly in performance

Peer education as an opportunity for practicing respect for sexual and gender diversity

This thesis asked the research question of how a peer educator intervention about LGBT peers can impact the social acceptance of LGBT people among students in pre-vocational secondary education. It answered the question by conducting two studies about the intervention’s impact on attitudes towards LGB people and its impact on reflections about democratic acting and the relationship between these two concepts. Furthermore, it used process evaluations with peer educators and students to shed light on which activities and content most influence students' attitudes towards LGBT people. Although there were often small or no effects on the relationships between reflections on citizenship and attitudes towards LGB people, the process evaluations show that a peer educator intervention creates conditions of openness and safety. Thus, students feel free to exchange opinions about a contested topic similar to how they would in daily life. Students find this a good way to become aware of their attitudes towards LGBT people and learn new information on an intimate subject. Teaching and Teacher Learning (ICLON