Risco de mercado na comercialização de energia elétrica: uma análise estruturada com foco no ambiente de contratação livre - ACL.

A motivação para o desenvolvimento desse trabalho surge em um momento em que se verifica uma participação cada vez mais significativa das fontes energéticas renováveis não convencionais no País. Não obstante, o cenário de evolução evidencia que o arcabouço regulatório e as regras de mercado não acompanharam as especificidades inerentes à exploração dessas fontes. Assim, para que se mantenha adequado ritmo de inserção na matriz energética, devem ser buscadas opções para que fontes alternativas sejam cada vez mais competitivas na atual configuração do mercado energético. A contribuição dessa pesquisa, portanto, centra-se na análise dos riscos de mercado incorridos por esses geradores de fontes intermitentes de energia ao comercializarem energia no ambiente de contratação livre. Nessa perspectiva, a Dissertação foi desenvolvida abordando tipos de geração de energia e suas características técnicas e econômicas, legislação do setor elétrico, regras de comercialização, balanço energético do sistema, formação de preços no mercado de curto prazo e precificação de contratos no ACL, diferença de preços entre submercados, requisitos de flexibilidade e sazonalidade nos contratos de venda a consumidores livres e seu impacto na precificação de contratos, identificação de comportamento energético complementar para mitigação de riscos de mercado entre fontes renováveis e rebatimento na formulação de mecanismo de hedge, análise de portfólio de contratos e estratégia ótima de contratação de energia para agentes geradores atuando no ACL. Como resposta ao desafio de equacionar o impasse surgido na comercialização de fontes de produção sazonal, propõe-se um modelo para definir estratégias de contratação para agentes geradores e comercializadores a partir da complementação energética entre diferentes tipos de fontes, de forma a maximizar os ganhos de comercialização para um risco estabelecido. Busca-se a composição ideal dessas fontes na carteira de um comercializador para minimizar o risco de exposição à volatilidade dos preços do mercado de curto prazo. Isso é possível em virtude das compensações energéticas feitas entre as diferentes fontes em um portfólio combinado, mitigando a receita em risco decorrente das variações que existem nos preços de curto prazo e na produção energética. De forma complementar, estruturou-se um modelo de negócio no qual uma empresa detentora de ativos de geração hidrelétrica compra os direitos de produção de uma eólica e/ou biomassa para incorporar ao seu portfólio e vender como contrato por quantidade. Determinou-se o volume de energia a ser comprado de cada fonte, o preço, a estratégia mais indicada de contratação e a mitigação de fatores de risco contemplados nos contratos de venda, buscando maximizar os ganhos de comercialização condicionada a critérios de risco pré-fixados.

Metodología para el estudio del brand-placement con enfoque de género: más allá del análisis de contenido

La mayoría de los estudios realizados sobre el tratamiento de género en la publicidad audiovisual se ciñen al formato convencional. Los nuevos formatos no se adecuan siempre a estos patrones. Con este fin, se ha elaborado un protocolo de análisis para estudiar la estructura del brand-placement, como forma no convencional de publicidad, en temas de género en la ficción española. Esta herramienta ha sido sometida a rigurosos controles de fiabilidad y validez con el ánimo de garantizar la confiabilidad y rigurosidad científica de las mismas, tanto en su composición como en su aplicación.

Theoretical insights on electron donor-acceptor interactions involving carbon dioxide

Electron donor-acceptor (EDA) interactions are widely involved in chemistry and their understanding is essential to design new technological applications in a variety of fields ranging from material sciences and chemical engineering to medicine. In this work, we study EDA complexes of carbon dioxide with ketones using several ab initio and Density Functional Theory methods. Energy contributions to the interaction energy have been analyzed in detail using both variational and perturbational treatments. Dispersion energy has been shown to play a key role in explaining the high stability of a non-conventional structure, which can roughly be described by a cooperative EDA interaction.

Crisis política y juventud en España: el declive del bipartidismo electoral

This paper shows the increasing trend of Spanish young people towards non-conventional mechanisms of political expression, in a crisis context which has reduced its reliance on traditional political actors. As an alternative to bipartisanship, political participation moves towards increased interest and attention to new players, such as emergent political parties. Using a covariance structural model, factors such as political activism, awareness and understanding of country problems, and trust in the political system, are explored in order to explain an electoral behavior that is undergoing deep changes.

Antiausteridad y protesta en el contexto de la crisis económica y política en España e Italia

The crisis affecting European Union, and especially Mediterranean countries, is both an economic and a political crisis. In a broad sense, we can look at the crisis as the result of an internal crisis of the neoliberal model, exacerbating the perceived subordination of politics to the economy, and therefore the deficit of legitimacy and involvement that characterizes both European and national institutions. The decline in support for traditional political organizations and reduction of conventional political participation is accompanied by a process of reinvention of politics, which takes form in grass-root, non conventional participation. New political actors challenge economic and political institution and claim for a renewal of democracy and for a new relation between economy and politics. The article, after comparing steps and dimension of crisis, explores the characteristics of anti- austerity movements in Spain and in Italy, analyzing differences and similarities. Finally, we locate the movilization occurred in these two countries within the context of the global cycles of protest.

Reiki como terapia não convencional: conhecimentos dos enfermeiros

Enquadramento: O interesse pelas Terapias Não Convencionais (TNC) teve um grande desenvolvimento no início deste século. O Reiki é uma terapia realizada através da colocação das mãos em pontos específicos do corpo e que utiliza a transferência de energia para proporcionar um bem-estar natural. A Enfermagem em especial a de Reabilitação, também apresenta dentro das suas intervenções específicas, uma vertente essencial baseada no toque à pessoa a quem presta cuidados, sendo por isso importante possuir conhecimentos sobre estas técnicas. Objetivos: Avaliar os conhecimentos dos enfermeiros acerca do Reiki e identificar fatores determinantes nesse conhecimento. Métodos: Trata-se de um estudo transversal, descritivo e correlacional, realizado numa amostra de 49 enfermeiros a exercer funções em instituições da região centro do país, baseado num questionário de conhecimentos elaborado pelas investigadoras. Resultados: Constatamos que os conhecimentos globais dos enfermeiros sobre o Reiki eram para 59,1% razoáveis, para 38,6% altos e apenas 2,3% apresentava baixos conhecimentos. Pudemos verificar diferenças estatisticamente significativas entre o “Conhecimento Total”, e as variáveis “ter iniciação em Reiki” e “ter recebido tratamento com Reiki” para o grupo de enfermeiros dos Cuidados Diferenciados (CD). Encontraram-se diferenças estatisticamente significativas, também, entre a dimensão “Conceito e História” e grupos etários, habilitações literárias, categoria profissional e tempo de serviço para os enfermeiros a exercer nos CD. Conclusão: Os conhecimentos dos enfermeiros sobre o Reiki são bastante significativos, sendo estes claramente superiores no grupo que exerce funções em CD. Por outro lado encontrámos fatores que interferem na determinação desses conhecimentos e que por isso importa controlar. Palavras-chave: Reiki; Enfermagem; Conhecimentos.

The influence of tool geometry on the performance of drilling tools

The main objective of the work presented in this thesis is to investigate the two sides of the flute, the face and the heel of a twist drill. The flute face was designed to yield straight diametral lips which could be extended to eliminate the chisel edge, and consequently a single cutting edge will be obtained. Since drill rigidity and space for chip conveyance have to be a compromise a theoretical expression is deduced which enables optimum chip disposal capacity to be described in terms of drill parameters. This expression is used to describe the flute heel side. Another main objective is to study the effect on drill performance of changing the conventional drill flute. Drills were manufactured according to the new flute design. Tests were run in order to compare the performance of a conventional flute drill and non conventional design put forward. The results showed that 50% reduction in thrust force and approximately 18% reduction in torque were attained for the new design. The flank wear was measured at the outer corner and found to be less for the new design drill than for the conventional one in the majority of cases. Hole quality, roundness, size and roughness were also considered as a further aspect of drill performance. Improvement in hole quality is shown to arise under certain cutting conditions. Accordingly it might be possible to use a hole which is produced in one pass of the new drill which previously would have required a drilled and reamed hole. A subsidiary objective is to design the form milling cutter that should be employed for milling the foregoing special flute from drill blank allowing for the interference effect. A mathematical analysis in conjunction with computing technique and computers is used. To control the grinding parameter, a prototype drill grinder was designed and built upon the framework of an existing cincinnati cutter grinder. The design and build of the new grinder is based on a computer aided drill point geometry analysis. In addition to the conical grinding concept, the new grinder is also used to produce spherical point utilizing a computer aided drill point geometry analysis.

The Cascade Orthogonal Neural Network

In the paper new non-conventional growing neural network is proposed. It coincides with the Cascade- Correlation Learning Architecture structurally, but uses ortho-neurons as basic structure units, which can be adjusted using linear tuning procedures. As compared with conventional approximating neural networks proposed approach allows significantly to reduce time required for weight coefficients adjustment and the training dataset size.

Phase noise tolerance study in coherent optical circular QAM transmissions with Viterbi- Viterbi carrier phase estimation

We present a performance evaluation of a non-conventional approach to implement phase noise tolerant optical systems with multilevel modulation formats. The performance of normalized Viterbi-Viterbi carrier phase estimation (V-V CPE) is investigated in detail for circular m-level quadrature amplitude modulation (C-mQAM) signals. The intrinsic property of C-mQAM constellation points with a uniform phase separation allows a straightforward employment of V-V CPE without the need to adapt constellation. Compared with conventional feed-forward CPE for square QAM signals, the simulated results show an enhanced tolerance of linewidth symbol duration product (ΔvTs) at a low sensitivity penalty by using feed-forward CPE structure with C-mQAM. This scheme can be easily upgraded to higher order modulations without inducing considerable complexity.

Heterodox gazdaságpolitikák korszaka? (An Age of Heterodox Economic Policies?)

A világ fejlett pénzügyi piacainak válságát követően önvizsgálatra kényszerült a közgazdaságtudomány, amelyet nemcsak az alternatív és heterodox irányzatok képviselői, a média és a nagyközönség, hanem a gazdasági döntéshozók részéről is erős kritikák értek. Egyidejűleg gyors változásokon ment át a gazdaságpolitikai gyakorlat, különösen a válság által erősen érintett országokban, megszaporodtak a korábbi mérvadó kormányzati gyakorlat (best practice) ajánlásaitól távol álló, nem szokványos megoldások, heterodox politikák. Az esszé szerzője meghatározó személyiségek véleményének, vezető intézmények álláspontjának és kormányzati gazdaságpolitikáknak az áttekintése alapján egyfelől azt a kérdést vizsgálja, hogy körvonalazódik-e új gazdaságelméleti irányzat, amely doktrinális alapul szolgálhatna a gazdaságpolitikai döntéshozatalhoz, másodsorban pedig: átmeneti jelenség-e az egymástól alapvetően különböző felfogású, logikájú gazdaságpolitikák egyidejű megléte, avagy várható-e egy új konszenzus kialakulása. ______ In the wake of the recent financial turmoil emanating from top financial centers, the economic profession has been forced to conduct introspection due to harsh criticism from alternative and heterodox economists, the media, and the general public as well as from decision makers. Meanwhile, the economic policy making practice has profoundly changed, particularly in countries heavily affected in the crisis; decision makers increasingly apply non customary (heterodox) measures in defiance of former best practice of economic policy making. The author of this essay, having investigated the related views of leading economists and influential international institutions and having reviewed economic policy making practice, raises two questions. One: is there a new economic theory evolving that will provide doctrinal underpinning to post crisis economic policy making? Second: is the simultaneity of widely differing economic policy practices and policy orientations a transitional phenomenon, or are there signs of a new policy consensus emerging? It may be too early to give argued answers to the questions, but the present – rather technical – economic theory mainstream seems to maintain its central position, yet is becomes more open to research topics and methods acknowledging the complexity of economic processes and social institutions, and to impulses emanating from economic practice. As for economic policy making is concerned, continuous decline of the economic importance of leading Western nations prolongs the period of heterogeneity of non conventional, heterodox policies both in advanced and in emerging countries until new policy norms, a “new normal” emerges.

Carbon nanotube based systems for high energy efficient applications

In the current age of fast-depleting conventional energy sources, top priority is given to exploring non-conventional energy sources, designing highly efficient energy storage systems and converting existing machines/instruments/devices into energy-efficient ones. ‘Energy efficiency’ is one of the important challenges for today’s scientific and research community, worldwide. In line with this demand, the current research was focused on developing two highly energy-efficient devices – field emitters and Li-ion batteries, using beneficial properties of carbon nanotubes (CNT). Interface-engineered, directly grown CNTs were used as cathode in field emitters, while similar structure was applied as anode in Li-ion batteries. Interface engineering was found to offer minimum resistance to electron flow and strong bonding with the substrate. Both field emitters and Li-ion battery anodes were benefitted from these advantages, demonstrating high energy efficiency. Field emitter, developed during this research, could be characterized by low turn-on field, high emission current, very high field enhancement factor and extremely good stability during long-run. Further, application of 3-dimensional design to these field emitters resulted in achieving one of the highest emission current densities reported so far. The 3-D field emitter registered 27 times increase in current density, as compared to their 2-D counterparts. These achievements were further followed by adding new functionalities, transparency and flexibility, to field emitters, keeping in view of current demand for flexible displays. A CNT-graphene hybrid structure showed appreciable emission, along with very good transparency and flexibility. Li-ion battery anodes, prepared using the interface-engineered CNTs, have offered 140% increment in capacity, as compared to conventional graphite anodes. Further, it has shown very good rate capability and an exceptional ‘zero capacity degradation’ during long cycle operation. Enhanced safety and charge transfer mechanism of this novel anode structure could be explained from structural characterization. In an attempt to progress further, CNTs were coated with ultrathin alumina by atomic layer deposition technique. These alumina-coated CNT anodes offered much higher capacity and an exceptional rate capability, with very low capacity degradation in higher current densities. These highly energy efficient CNT based anodes are expected to enhance capacities of future Li-ion batteries.

Serious Game no tratamento de obesidade infantil: uma proposta de interação natural com monitoramento remoto

The number of overweight people has increased in the last few years. Factors such as attention to diet and changes in lifestyle are crucial in the prevention and control of obesity and diseases related to it. Experts believe that such actions are most effective when initiated during childhood, and that children raised in an environment that encourages physical activity ultimately become healthier adults. However, to arouse and maintain interest in such activities represent a major challenge, which are initially perceived as repetitive and boring, and, thus, soon abandoned. Computer games, traditionally seen as stimulants to a sedentary lifestyle are changing this perception using non-conventional controls that require constant movement of the player. Applications that combine the playfulness of such games to physical activity through devices, like Microsoft Kinect, might become interesting tools in this scenario, by using the familiarity of Natural User Interfaces along with the challenge and the fun of video games, in order to make attractive exercise routines for schoolchildren. The project carried out consists of an exergame composed of several activities designed and implemented with the participation of a Physical Educator, aimed at children between eight and ten years old, whose performance and progress can be remotely monitored by a professional via web interface. The application arising from this work was accompanied by tests with a group of graduating Physical Education students from the University of Rio Verde GO, and subsequently validated through questionnaires whose results are shown on this work.

Efeito da concentração de sólidos e de variáveis operacionais no desempenho de um hidrociclone concentrador

The hydrocycloning operation has a goal to separate solid-liquid suspensions and liquid-liquid emulsions through the centrifugal force action. Hydrocyclones are equipment with reduced size and used in both clarification and thickening. This device is used in many areas, like petrochemical and minerals process, and accumulate advantages like versatility and low cost of maintenance. However, the demand to improve the process and to reduce the costs has motivated several studies of equipment optimization. The filtering hydrocyclone is a non-conventional equipment developed at FEQUI/UFU with objective to improve the hydrocycloning separation efficiency. The purpose of this study is to evaluate the operating conditions of feed concentration and underflow diameter on the performance of a filtering geometry optimized to minimization of energy costs. The filtration effect was investigated through the comparison between the performance of the Optimized Filtering Hydrocyclone (HCOF) and the Optimized Concentrator Hydrocyclone (HCO). Because of the resemblance of hydrocyclones performance, the filtration did not represent significant effect on the performance of the HCOF. It was found that in this geometry the decrease of the variable underflow diameter was very favorable to thickening operation. The suspension concentration of quartzite at 1.0% of solids in volume was increased about 42 times when the 3 mm underflow diameter was used. The increase on the feed solid percentage was good for decreasing the energy spent, so that a minimum number of Euler of 730 was achieved at CVA = 10.0%v. However, a greater amount of solids in suspension leads to a lower efficiency of the equipment. Therefore, to minimize the underflow-to-throughput ratio and keep a high efficiency level, it is indicated to work with dilute suspension (CVA = 1.0%) and 3 mm underflow diameter (η = 67%). But if it is necessary to work with high feed concentration, the use of 5 mm underflow diameter provides a rise in the efficiency. The HCO hydrocyclone was compared to the traditional family of hydrocyclones Rietema and presented advantages like higher efficiency (34% higher in average) and lower energy costs (20% lower in average). Finally, the efficiency curves and project equation have been raised for the HCO hydrocyclone each with satisfactory adjust.

Fatores que influenciam o uso do marketing de guerrilha nas empresas em Portugal

Atualmente vivemos numa era em que a publicidade nos rodeia através de várias formas e onde as empresas esforçam-se cada vez mais para tornar eficaz a mensagem que pretendem passar. O uso de métodos convencionais, como a televisão, rádio, ou até outdoors, está a tornar-se pouco eficaz. Em muito pouco tempo, nos últimos vinte anos, a Internet mudou a nossa forma de viver, sendo até comparado ao Renascimento e à Revolução Industrial. As gerações mais recentes nasceram rodeadas deste “boom” publicitário, o que as tornou imunes. De forma a contornar este problema, surge Levinson em 1989 onde apresenta uma forma de minimizar este efeito e ao mesmo tempo proporcionar a que pequenas empresas tenham capacidade de competir com as maiores (Levinson, 2007). Assim, o marketing de guerrilha caracteriza-se por estar normalmente associado a implementações de baixo custo, que por vezes são irrepetíveis, pois conseguem alcançar um impacto “wow” significativo junto do grande público (Oliveira & Ferreira, 2013). O presente estudo contribui para a literatura do marketing de guerrilha existente, realizando assim uma compilação acerca do desenvolvimento desta temática até aos dias de hoje. De forma a perceber quais são os fatores que influenciam o uso do marketing de guerrilha pelas empresas portuguesas, foram inquiridas 140 empresas de todo o país, através de um questionário com base no estudo desenvolvido por Overbeek (2012). Através desta investigação exploratória, numa área ainda pouco explorada em Portugal, até à data, em especial a nível académico, “verificou-se que existe uma grande procura por este tipo de ferramentas não convencionais, tanto que, verificou-se que 86,4% da amostra já presenciou uma ação de guerrilha, no entanto apenas 36,4% admite já ter implementado na sua empresa, o que levanta a questão do porquê de uma taxa tão reduzida de utilização deste tipo de abordagem não convencional (Almeida & Au-Yong-Oliveira, 2015, p.1). A explicação poderá estar ligada à grande aversão à incerteza que existe em Portugal (Hofstede, 2001), e ao receio da mudança e da experimentação de novos produtos em Portugal (Steenkamp et al., 1999). Fatores que não irão mudar durante décadas, dado o tempo que demora a mudar culturas nacionais (Hofstede, 2001). Verifica-se também que na amostra das 140 empresas se destacam pessoas formadas (ao grau de licenciatura e mestrado) em Marketing (18,7% da amostra), Design (15,7%), Gestão (10,4%) e Tecnologias da Informação e Comunicação (7,9%). Pode-se concluir que são as quatro áreas fundamentais, ou pelo menos a necessidade existe em ter conhecimento nestas quatro áreas atualmente. Devido à [pequena] dimensão das empresas, um colaborador que tenha estas quatro competências tem uma vantagem competitiva face aos restantes, no que toca a hard skills.

Métabolomique et spectrométrie de masse : de nouvelles perspectives en analyse biomédicale

International audience