Electromagnetism based approach to Sector design in Waste Collection

For efficient planning of waste collection routing, large municipalities may be partitioned into convenient sectors. The real case under consideration is the municipality of Monção, in Portugal. Waste collection involves more than 1600 containers over an area of 220 km2 and a population of around 20,000 inhabitants. This is mostly a rural area where the population is distributed in small villages around the 33 boroughs centres (freguesia) that constitute the municipality. In most freguesias, waste collection is usually conducted 3 times a week. However, there are situations in which the same collection is done every day. The case reveals some general and specific characteristics which are not rare, but are not widely addressed in the literature. Furthermore, new methods and models to deal with sectorization and routing are introduced, which can be extended to other applications. Sectorization and routing are tackled following a three-phase approach. The first phase, which is the main concern of the presentation, introduces a new method for sectorization inspired by Electromagnetism and Coulomb’s Law. The matter is not only about territorial division, but also the frequency of waste collection, which is a critical issue in these types of applications. Special characteristics related to the number and type of deposition points were also a motivation for this work. The second phase addresses the routing problems in each sector: new Mixed Capacitated Arc Routing with Limited Multi-Landfills models will be presented. The last phase integrates Sectoring and Routing. Computational results confirm the effectiveness of the entire novel approach.

HIV Voluntary Testing among Portuguese Women Attending Family Planning Clinics: Implications for HIV Prevention Education and Testing

Objectives: The aim of this article is to analyze the factors associated with HIV testing among 767 sexually active women. Methods: Participants were administered several self-report questionnaires that assessed behavioral and psychosocial measures. Results: Overall, 59.8% of the participants reported ever having tested for HIV. Results show that higher levels of education, being pregnant or having been pregnant, concern about AIDS, AIDS knowledge, self-efficacy in condom negotiation and perception of no risk in partner significantly predicted the likelihood of testing among women. Attending the mass was negatively associated with HIV testing. Conclusions: These findings provide information that can be used in the development of a focused gender sensitive HIV prevention program to increase HIV testing.

Predictors of consistent condom use among Portuguese women attending family planning clinics

Women account for 30% of all AIDS cases reported to the Health Ministry in Portugal and most infections are acquired through unprotected heterosexual sex with infected partners. This study analyzed socio-demographic and psychosocial predictors of consistent condom use and the role of education as a moderator variable among Portuguese women attending family planning clinics. A cross-sectional study using interviewer-administered fully structured questionnaires was conducted among 767 sexually active women (ages 18–65). Logistic regression analyses were used to explore the association between consistent condom use and the predictor variables. Overall, 78.7% of the women were inconsistent condom users. The results showed that consistent condom use was predicted by marital status (being not married), having greater perceptions of condom negotiation self-efficacy, having preparatory safer sexual behaviors, and not using condoms only when practicing abstinence. Living with a partner and having lack of risk perception significantly predicted inconsistent condom use. Less educated women were less likely to use condoms even when they perceive being at risk. The full model explained 53% of the variance in consistent condom use. This study emphasizes the need for implementing effective prevention interventions in this population showing the importance of taking education into consideration.