Kompetansekonstruksjoner i matematikk og programfag. Utdanningsprogrammet bygg- og anleggsteknikk, videregående opplæring

The study that this dissertation reports from, was motivated by an aim to find information about how to make teaching of mathematics for students enrolled in the building and construction programme in Norwegian upper secondary school more relevant. The study is situated in a constructionist paradigm (Creswell, 2013; Guba & Lincoln, 1994; Mertens, 2014). It is a case study where I have followed a single class of students enrolled in the programme building and construction for one year, in both building and construction subjects and in the subject of mathematics. Situative perspectives generally (Greeno et al., 1996) and more specifically Wenger (1998) , Communities of practice, are used as a theoretical basis. The community in the building- and construction subjects (referred to as the workshop) and the community in the mathematics classroom are conceptualized as two different communities of practice. It became apparent that there were major differences in how the students participated in the workshop compared to the mathematics classroom, and the study reports on different constructions of competence in the two communities of practice. I discuss possible consequences that the two different constructions of competence may have for learning and knowledge, and also for the students’ identification with the different communities. This discussion is based mainly on Wenger’s social practice theory. At the end of the dissertation, I discuss how the results from my study may contribute towards making teaching of mathematics more relevant for students enrolled in the building and construction programme.publishedVersio

Study of different subcooling control strategies in order to enhance the performance of a heat pump

[EN] The performance of vapor-compression systems working with subcritical refrigerants varies with the degree of subcooling. There is an optimal subcooling that maximizes efficiency. However, it depends on the operating conditions and the control of the system needs to be adapted. Most of the works available in literature are able to operate in optimal conditions only at the design point or if a system is designed to be able to adapt its subcooling, only complex control algorithms that usually are difficult to set and time-costly, are used. This work focuses on the study of the main variables influencing the optimal subcooling and analyzes two different control methodologies from the theoretical point of view. Based on the theoretical study a final control strategy is selected and tested experimentally. The reliability, stability and robustness of the selected strategy are experimentally demonstrated for a wide set of operating conditions. (c) 2018 Elsevier Ltd and IIR. All rights reserved.Part of the work presented was carried by Estefania Hervas Blasco with the financial support of a PhD scholarship from the Spanish government SFPI1500 x 074478XV0. The authors would like also to acknowledge the Spanish 'MINISTERIO DE ECONOMIA Y COMPETITIVIDAD', through the project. "MAXIMIZACION DE LA EFICIENCIA Y MINIMIZACION DEL IMPACTO AMBIENTAL DE BOMBAS DE CALOR PARA LA DESCARBONIZACION DE LA CALEFACCION/ACS EN LOS EDIFICIOS DECONSUMO CASI NULO" with the reference ENE2017-83665-C2-1-P for the given support.Hervas-Blasco, E.; Pitarch, M.; Navarro-Peris, E.; Corberán, JM. (2018). Study of different subcooling control strategies in order to enhance the performance of a heat pump. International Journal of Refrigeration. 88:324-336. https://doi.org/10.1016/j.ijrefrig.2018.02.003S3243368

Kompetansekonstruksjoner i matematikk og programfag

Studien denne avhandlingen rapporterer fra, var motivert av å skaffe informasjon om hvordan matematikkundervisningen for elever på bygg- og anleggstekniske fag i videregående opplæring i Norge kunne gjøres mer relevant. Studien er forankret i et konstruksjonistisk forskningsparadigme (Creswell, 2013; Guba & Lincoln, 1994; Mertens, 2014). Mer spesifikt er studien en casestudie der jeg har fulgt en klasse ved utdanningsprogrammet bygg- og anleggsteknikk over ett år i programfagene (altså bygg- og anleggsrelaterte fag) og i matematikkfaget. Situative perspektiver generelt (Greeno, Collins, & Resnick, 1996) , og hovedsakelig Wenger (1998), Communities of practice, er brukt som teoretisk rammeverk. I studien har jeg ansett fellesskapet i programfagene (referert til som verkstedet) og fellesskapet i matematikk-klasserommet som to ulike praksisfelleskap. Det viste seg at det var store forskjeller i hvordan elevene deltok i verkstedet sammenliknet med i matematikk-klasserommet, og studien rapporterer først om ulike kompetansekonstruksjoner i de to fellesskapene. Videre drøfter jeg hvilke konsekvenser de ulike kompetansekonstruksjonene kan ha for kunnskap og læring, men også for elevenes identitetsrelasjoner til fellesskapene, i et teoretisk perspektiv. Hovedsakelig har jeg tatt utgangspunkt i Wengers sosiale praksisteori i drøftingen. Til slutt i avhandlingen forsøker jeg å se framover, og jeg drøfter hva resultatene fra min studie kan bidra med i å gjøre matematikkundervisning relevant for elever på bygg- og anleggsteknikk