Affine invariant fitting of algebraic curves using Fourier descriptors

Both parametric and implicit representations are used in a variety of computer vision applications such as object modeling, recognition and pose estimation. In this paper, we present a new algebraic curve fitting technique based on the implicitization of affine invariant Fourier descriptors that can be used to model free-form objects captured from different viewpoints. Implicitization can be carried out quite efficiently using a numerical procedure rather than computing determinants of eliminant matrices, symbolically. Affine invariance of the proposed fitting technique is experimentally shown on a database of 2D free-form objects. Experimental results are provided to assess the robustness of our fitting method under data perturbations. Some invariant recognition examples are also presented

Can the impact of gender equality on health be measured? a cross-sectional study comparing measures based on register data with individual survey-based data

BACKGROUND: The aim of this study was to investigate potential associations between gender equality at work and self-rated health. METHODS: 2861 employees in 21 companies were invited to participate in a survey. The mean response rate was 49.2%. The questionnaire contained 65 questions, mainly on gender equality and health. Two logistic regression analyses were conducted to assess associations between (i) self-rated health and a register-based company gender equality index (OGGI), and (ii) self-rated health and self-rated gender equality at work. RESULTS: Even though no association was found between the OGGI and health, women who rated their company as "completely equal" or "quite equal" had higher odds of reporting "good health" compared to women who perceived their company as "not equal" (OR = 2.8, 95% confidence interval = 1.4 -- 5.5 and OR = 2.73, 95% CI = 1.6-4.6). Although not statistically significant, we observed the same trends in men. The results were adjusted for age, highest education level, income, full or part-time employment, and type of company based on the OGGI. CONCLUSIONS: No association was found between gender equality in companies, measured by register-based index (OGGI), and health. However, perceived gender equality at work positively affected women's self-rated health but not men's. Further investigations are necessary to determine whether the results are fully credible given the contemporary health patterns and positions in the labour market of women and men or whether the results are driven by selection patterns.Artikeln har vid publiceringen fått en annan titel än den hade vid publiceringen av avhandlingen. Tidigare titel: Do gender-equal workplaces contribute to good health?</p