The Alamouti Scheme with CDMA-OFDM/OQAM

This paper deals with the combination of OFDM/OQAM with the Alamouti scheme. After a brief presentation of the OFDM/OQAM modulation scheme, we introduce the fact that the well-known Alamouti decoding scheme cannot be simply applied to this modulation. Indeed, the Alamouti coding scheme requires a complex orthogonality property; whereas OFDM/OQAM only provides real orthogonality. However, as we have recently shown, under some conditions, a transmission scheme combining CDMA and OFDM/OQAM can satisfy the complex orthogonality condition. Adding a CDMA component can thus be seen as a solution to apply the Alamouti scheme in combination with OFDM/OQAM. However, our analysis shows that the CDMA-OFDM/OQAM combination has to be built taking into account particular features of the transmission channel. Our simulation results illustrate the 2×1 Alamouti coding scheme for which CDMA-OFDM/OQAM and CP-OFDM are compared in two different scenarios: (i) CDMA is performed in the frequency domain, (ii) CDMA is performed in time domain

Cálculo automático de estruturas: análise estrutural de pórticos tridimensionais

No âmbito da presente dissertação foi elaborado um programa de cálculo automático de pórticos tridimensionais, sob acções estáticas (Portic3D). Utilizaram-se elementos tipo barra 3D constituídos por dois pontos nodais com seis graus de liberdade cada, admitindo a hipótese de comportamento elástico linear do material. Apresentam-se os fundamentos da análise matricial de estruturas e descrevem-se os principais módulos computacionais que foram elaborados (em FORTRAN 90), nomeadamente descreve-se a estrutura global do programa desenvolvido e, em particular, descreve-se a técnica de assemblagem da matriz de rigidez global e do vector global das forças a partir das matrizes de rigidez elementares e dos vectores elementares das forças nodais equivalentes às cargas de vão, respectivamente. A fiabilidade do programa desenvolvido, Portic3D, foi testada através da comparação com os resultados de um programa de cálculo estrutural de referência, o SAP2000, para o caso da análise estática de um edifício de 8 pisos (sob a acção do peso próprio, sobrecargas e forças estáticas equivalentes a uma acção sísmica). Foi elaborado ainda um manual do utilizador para facilitar a utilização do software desenvolvido e para facilitar a eventual integração das rotinas desenvolvidas em programas de cálculo estrutural com novas potencialidades

Des/igualdades de género na Força Aérea Portuguesa: mudanças e permanências

A presente dissertação pretendeu analisar as mudanças nas relações de género registadas na Força Aérea desde a entrada das mulheres neste contexto, há cerca de 30 anos, até à atualidade. Para tal, foi realizado um estudo empírico com os objetivos específicos de verificar se se percebem mudanças nas relações entre homens e mulheres na Força Aérea entre o passado e o presente; e se há diferenças de opinião entre homens e mulheres militares relativamente a esta questão. Foram realizadas 12 entrevistas individuais semiestruturadas a militares da Força Aérea, seis homens e seis mulheres, com idades compreendidas entre os 44 e os 54 anos, com uma larga experiência no contexto militar. Os entrevistados ingressaram todos na Força Aérea antes da entrada das mulheres e as entrevistadas entraram entre 1992 e 1994. Os dados foram analisados recorrendo ao método da análise temática de Braun e Clarke (2006), que nos permitiu identificar cinco grandes temas sobre: i) relações de género no passado; ii) mudanças provocadas pelo ingresso das mulheres na Força Aérea; iii) relações hierárquicas e de poder; iv) desequilíbrios e desigualdades de género e diferenças de sexo na Força Aérea; e v) relações de género no presente. Verificam-se grandes mudanças nas relações de género na Força Aérea, que são unanimamente consideradas agora mais “normais” e equilibradas, em comparação com as da realidade mais tradicional que existia quando as mulheres ingressaram na Força Aérea, há cerca de 30 anos. Atualmente, as mulheres sentem-se perfeitamente integradas na organização e os homens entendem que já não existem diferenças de género.This dissertation aimed to analyze the changes in gender relations registered in the Air Force since the entry of women in this context, about 30 years ago, until today. To this end, an empirical study was carried out with the specific objectives of verifying whether they perceive changes in the relations between men and women in the Air Force between the past and the present; and whether there are differences of opinion between military men and women on this issue. Twelve individual semi-structured interviews were conducted with Air Force military personnel, six men and six women, aged between 44 and 54 years, with extensive experience in the military context. The interviewees all joined the Air Force before the women entered and the interviewees entered between 1992 and 1994. The data were analyzed using the method of thematic analysis by Braun and Clarke (2006), which allowed us to identify five major themes on: i) gender relations in the past; ii) changes brought about by the entry of women into the Air Force; iii) hierarchical and power relations; iv) gender imbalances and inequalities and gender differences in the Air Force; and v) gender relations in the present. There are major changes in gender relations in the Air Force, which are unanimously considered now more “normal” and balanced, compared to the more traditional reality that existed when women joined the Air Force 30 years ago. Today, women feel perfectly integrated into the organization and men understand that there are no longer any gender differences

A One Health Evaluation of the Southern African Centre for Infectious Disease Surveillance

Rooted in the recognition that emerging infectious diseases occur at the interface of human, animal, and ecosystem health, the Southern African Centre for Infectious Disease Surveillance (SACIDS) initiative aims to promote a trans-sectoral approach to address better infectious disease risk management in five countries of the Southern African Development Community. Nine years after SACIDS’ inception, this study aimed to evaluate the program by applying a One Health (OH) evaluation framework developed by the Network for Evaluation of One Health (NEOH). The evaluation included a description of the context and the initiative, illustration of the theory of change, identification of outputs and outcomes, and assessment of the One Healthness. The latter is the sum of characteristics that defines an integrated approach and includes OH thinking, OH planning, OH working, sharing infrastructure, learning infrastructure, and systemic organization. The protocols made available by NEOH were used to develop data collection protocols and identify the study design. The framework relies on a mixed methods approach by combining a descriptive and qualitative assessment with a semi-quantitative evaluation (scoring). Data for the analysis were gathered during a document review, in group and individual interviews and in an online survey. Operational aspects (i.e., OH thinking, planning, and working) were found to be balanced overall with the highest score in the planning dimension, whereas the infrastructure (learning infrastructure, systemic organization, and sharing infrastructure) was high for the first two dimensions, but low for sharing. The OH index calculated was 0.359, and the OH ratio calculated was 1.495. The program was praised for its great innovative energy in a difficult landscape dominated by poor infrastructure and its ability to create awareness for OH and enthuse people for the concept; training of people and networking. Shortcomings were identified regarding the balance of contributions, funds and activities across member countries in the South, lack of data sharing, unequal allocation of resources, top-down management structures, and limited horizontal collaboration. Despite these challenges, SACIDS is perceived to be an effective agent in tackling infectious diseases in an integrated manner

A systems approach to evaluate One Health initiatives

Challenges calling for integrated approaches to health, such as the One Health (OH) approach, typically arise from the intertwined spheres of humans, animals, and ecosystems constituting their environment. Initiatives addressing such wicked problems commonly consist of complex structures and dynamics. As a result of the EU COST Action (TD 1404) “Network for Evaluation of One Health” (NEOH), we propose an evaluation framework anchored in systems theory to address the intrinsic complexity of OH initiatives and regard them as subsystems of the context within which they operate. Typically, they intend to influence a system with a view to improve human, animal, and environmental health. The NEOH evaluation framework consists of four overarching elements, namely: (1) the definition of the initiative and its context, (2) the description of the theory of change with an assessment of expected and unexpected outcomes, (3) the process evaluation of operational and supporting infrastructures (the “OH-ness”), and (4) an assessment of the association(s) between the process evaluation and the outcomes produced. It relies on a mixed methods approach by combining a descriptive and qualitative assessment with a semi-quantitative scoring for the evaluation of the degree and structural balance of “OH-ness” (summarised in an OH-index and OH-ratio, respectively) and conventional metrics for different outcomes in a multi-criteria-decision-analysis. Here, we focus on the methodology for Elements (1) and (3) including ready-to-use Microsoft Excel spreadsheets for the assessment of the “OH-ness”. We also provide an overview of Element (2), and refer to the NEOH handbook for further details, also regarding Element (4) (http://neoh.onehealthglobal.net). The presented approach helps researchers, practitioners, and evaluators to conceptualise and conduct evaluations of integrated approaches to health and facilitates comparison and learning across different OH activities thereby facilitating decisions on resource allocation. The application of the framework has been described in eight case studies in the same Frontiers research topic and provides first data on OH-index and OH-ratio, which is an important step towards their validation and the creation of a dataset for future benchmarking, and to demonstrate under which circumstances OH initiatives provide added value compared to disciplinary or conventional health initiatives

Bionomics of Anopheline species and malaria transmission dynamics along an altitudinal transect in Western Cameroon

<p>Abstract</p> <p>Background</p> <p>Highland areas of Africa are mostly malaria hypoendemic, due to climate which is not appropriate for anophelines development and their reproductive fitness. In view of designing a malaria control strategy in Western Cameroon highlands, baseline data on anopheline species bionomics were collected.</p> <p>Methods</p> <p>Longitudinal entomological surveys were conducted in three localities at different altitudinal levels. Mosquitoes were captured when landing on human volunteers and by pyrethrum spray catches. Sampled <it>Anopheles </it>were tested for the presence of <it>Plasmodium </it>circumsporozoite proteins and their blood meal origin with ELISA. Entomological parameters of malaria epidemiology were assessed using Mac Donald's formula.</p> <p>Results</p> <p>Anopheline species diversity and density decreased globally from lowland to highland. The most aggressive species along the altitudinal transect was <it>Anopheles gambiae </it>s.s. of S molecular form, followed in the lowland and on the plateau by <it>An. funestus</it>, but uphill by <it>An. hancocki</it>. <it>An. gambiae </it>and <it>An. ziemanni </it>exhibited similar seasonal biting patterns at the different levels, whereas different features were observed for <it>An. funestus</it>. Only indoor resting species could be captured uphill; it is therefore likely that endophilic behaviour is necessary for anophelines to climb above a certain threshold. Of the ten species collected along the transect, only <it>An. gambiae </it>and <it>An. funestus </it>were responsible for malaria transmission, with entomological inoculation rates (EIR) of 90.5, 62.8 and zero infective bites/human/year in the lowland, on the plateau and uphill respectively. The duration of gonotrophic cycle was consistently one day shorter for <it>An. gambiae </it>as compared to <it>An. funestus </it>at equal altitude. Altitudinal climate variations had no effect on the survivorship and the subsequent life expectancy of the adult stage of these malaria vectors, but most probably on aquatic stages. On the contrary increasing altitude significantly extended the duration of gonotrophic cycle and reduced: the EIR, their preference to human blood and consequently the malaria stability index.</p> <p>Conclusion</p> <p>Malaria epidemiological rooting in the outskirts of Western Cameroon highlands evolves with increasing altitude, gradually from stable to unstable settings. This suggests a potential risk of malaria epidemic in highlands, and the need for a continuous epidemiological surveillance.</p