Exploratory investigation of the effect of nylon grain size on ablation of phenolic nylon

Exploratory investigation of nylon grain size effect on ablation of phenolic nylo

The Relationship between Preschool Teachers’ Knowledge, and Experience to Emergent Literacy Assessment

Current research suggests that preschool teachers lack the content knowledge in phonemic awareness for ensuring the development of young children’s early literacy skills. This exploratory study examined the relationship between preschool teachers’ content knowledge in early literacy, education level, and years of teaching experience to emergent literacy assessment; and if differences in students’ emergent literacy assessment across different preschool program settings was significant. Results from a multiple regression analysis indicated the findings were not significant. However, in conducting simple linear regression analyses, preschool teachers’ content knowledge in early literacy had a predictive relationship with students’ emergent literacy skills. Results from a one-way ANOVA found emergent literacy assessment scores for the pre-kindergarten group as significant from the Head Start group. Recommended Citation Crouch, M. G. (2020, October 1-2). The relationship between preschool teachers’ knowledge, and experience to emergent literacy assessment [Poster presentation]. Walden University Research Conference 2020 (online). https://scholarworks.waldenu.edu/researchconference/2020/posters/27

Online optimization of casualty processing in major incident response: An experimental analysis

When designing an optimization model for use in mass casualty incident (MCI) response, the dynamic and uncertain nature of the problem environment poses a significant challenge. Many key problem parameters, such as the number of casualties to be processed, will typically change as the response operation progresses. Other parameters, such as the time required to complete key response tasks, must be estimated and are therefore prone to errors. In this work we extend a multi-objective combinatorial optimization model for MCI response to improve performance in dynamic and uncertain environments. The model is developed to allow for use in real time, with continuous communication between the optimization model and problem environment. A simulation of this problem environment is described, allowing for a series of computational experiments evaluating how model utility is influenced by a range of key dynamic or uncertain problem and model characteristics. It is demonstrated that the move to an online system mitigates against poor communication speed, while errors in the estimation of task duration parameters are shown to significantly reduce model utility

Temperature profiles in high gradient furnaces

Accurate temperature measurement of the furnace environment is very important in both the science and technology of crystal growth as well as many other materials processing operations. A high degree of both accuracy and precision is acutely needed in the directional solidification of compound semiconductors in which the temperature profiles control the freezing isotherm which, in turn, affects the composition of the growth with a concomitant feedback perturbation on the temperature profile. Directional solidification requires a furnace configuration that will transport heat through the sample being grown. A common growth procedure is the Bridgman Stockbarger technique which basically consists of a hot zone and a cold zone separated by an insulator. In a normal growth procedure the material, contained in an ampoule, is melted in the hot zone and is then moved relative to the furnace toward the cold zone and solidification occurs in the insulated region. Since the primary path of heat between the hot and cold zones is through the sample, both axial and radial temperature gradients exist in the region of the growth interface. There is a need to know the temperature profile of the growth furnace with the crystal that is to be grown as the thermal load. However it is usually not feasible to insert thermocouples inside an ampoule and thermocouples attached to the outside wall of the ampoule have both a thermal and a mechanical contact problem as well as a view angle problem. The objective is to present a technique of calibrating a furnace with a thermal load that closely matches the sample to be grown and to describe procedures that circumvent both the thermal and mechanical contact problems

Regeneration of Old Ungrazed Old Man Saltbush (\u3ci\u3eAtriplex nummularia\u3c/i\u3e) Stands in South-West Australia

Many old man saltbush (Atriplex nummularia) stands were sown in the grainbelt of Western Australia for soil regeneration and salinity management up to 25 years ago, but have not been effectively grazed subsequently, such that the main feed available for sheep is above grazing height. The aim of the study was therefore to see if it was possible to return the old man saltbush stands to a productive grazing stand. Two sites were chosen that had been sown up to 25 years previously in Goomalling and Corrigin, in the south-west of Western Australia. The sites were split into four treatments that would reduce the height of the stands and bring all grazing material back to less than 1.2 m (the maximum grazing height for sheep in Australia); cutting to 0.5 m, cutting to 1 m, rolling to ground level, and a uncut control. Available feed above and below 1.2 m was assessed before cutting or rolling and then four times over the next two years. The results found that all three treatments removed feed above 1.2 m and that after 2 years the amount of feed below 1.2 m was increasing. The greatest feed available below 1.2 m was in the rolled treatment, followed by cutting to 0.5 m. Cutting old man saltbush stands to 1 m provides greater feed on the plants after cutting, but within one year of cutting some of the new feed is already above grazing height. It is concluded there is potential to return old established stands of old man saltbush to a productive grazing stand