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Mercado de derivados: weather derivatives

Carvalho, Sofia Raquel Pestana de
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2009 Português
Relevância na Pesquisa
16.83%
Mestrado em Marketing / JEL Classification System: Q40, G13; Num clima económico cada vez mais incerto, a maior necessidade de ferramentas para cobertura de risco e crescente sofisticação dos investidores representam tendências importantes para impulsionar o crescimento e a inovação do mercado de derivados. Neste contexto procurou-se perceber o funcionamento destes mercados, bem como as vantagens que estes incorporam no funcionamento da economia, ao cobrirem os diversos riscos a que as empresas incorrem no desenrolar da sua actividade económica. Em todo o mundo, estima-se que cerca de quatro quintos da actividade económica é afectada directa ou indirectamente pelo clima. O impacto das condições climatéricas verificadas é sentido por muitos sectores de actividade, sendo exemplo o sector da energia. Uma das variáveis críticas das empresas deste sector é o consumo de energia para aquecimento de lares e empresas. Este diminui durante um Inverno menos frio que o normal, afectando negativamente o lucro das empresas fornecedoras de energia naquele ano, com um resultado inferior ao previsto. Para que haja uma imunização dos resultados das empresas face ao risco que incorrem de as condições climáticas não serem as esperadas...

O preço do petróleo como factor global: análise sectorial

Martinho, Isabel Rodrigues
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2010 Português
Relevância na Pesquisa
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Mestrado em Finanças/ G12; Q40; Nos últimos anos tornou-se bastante popular o investimento em commodities, nomeadamente, em petróleo. Entre as várias possibilidades que existem, uma delas é o investimento em acções de empresas do sector petrolífero. Esta tese emprega um modelo multifactorial para identificar, no período 2000-2009, os principais determinantes da rendibilidade dos sectores de produtores de petróleo e gás; equipamentos, serviços e distribuição de petróleo; energias alternativas; químico e indústria mineira e de metais, com destaque para a importância do petróleo. Os nove países considerados têm representatividade global ao nível da produção e do consumo mundial diário de petróleo. Os resultados obtidos evidenciam uma relação positiva e com relevância estatística das variações semanais dos preços do petróleo na rendibilidade dos sectores de produtores de petróleo e gás; equipamentos, serviços e distribuição de petróleo e indústria mineira e de metais. Tal impacto verifica-se na maioria dos países, podendo-se concluir que o petróleo tem importância no investimento destes sectores. Na maioria dos países e nos sectores de energias alternativas e químico o petróleo tem...

Plano de comunicação digital para a eficiência energética

Costa, Diana Moutinho de Sousa
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2012 Português
Relevância na Pesquisa
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Projeto de Mestrado em Marketing / Classificação JEL: D83, Q40, M37; A Eficiência Energética pode contribuir para a redução das emissões mundiais de dióxido de carbono em 72% até 2020, segundo as previsões do World Energy Outlook (IEA, 2011). Simultaneamente, a Comunicação Digital e o Marketing Verde revelam-se como duas tendências de importância crescente para os consumidores, que são cada vez mais exigentes (Afonso, 2011), o que obriga a que a comunicação se torne cada vez mais interactiva e portadora de conteúdos verdadeiramente relevantes (Dionísio et al, 2009 e Scott, 2011). Verifica-se, contudo, a necessidade de disponibilizar aos consumidores incentivos (Fogg, 2011) que eliminem as barreiras que ainda existem à adopção de comportamentos eficientes, em particular nos indivíduos com idade até aos 25 anos (Energy Profiler, 2011). Embora os consumidores identifiquem o termo “eficiência energética”, não sabem ainda ao certo o que podem fazer para se tornarem eficientes (Murphy et al, 2010). Esta investigação concluiu que utilizar comunicação digital para divulgar a eficiência energética não influencia significativamente o interesse sobre este tema junto dos indivíduos até aos 25 anos de idade. Contudo...

Stochastic Evaluation of Deepwater oil prospects in Portugal using Monte Carlo Simulation

Camelo, André Rodrigues Seatra
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 25/03/2014 Português
Relevância na Pesquisa
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Master in Finance/ Classificação: Q40; C63; O22; Portugal, como muitos outros países, é um importador de petróleo, porém, é um dos poucos países com potencial para grandes descobertas de óleo, ao longo de sua zona exclusiva econômica inexplorada. O potencial é justificado a partir da semelhança geológica, com as recentes descobertas em águas profundas, no outro lado do Oceano Atlântico (Brasil, Golfo do México e do Canadá Oriental). Este estudo executa a metodologia de avaliação estocástica, para estimar o potencial petrolífero das concessões de águas profundas, na Bacia de Peniche e Alentejo. O ciclo de vida de um projeto no sector de Oil&Gas, incorpora incertezas importantes relacionadas com rendimentos e custos. As principais incertezas prendem-se com os Volumes Recuperáveis de óleo, com as Taxas de Produção, o preço do Brent e com a estrutura de Capex&Opex. Os Volumes de óleo recuperáveis são calculados e enquadrados de acordo com o software geológico, GeoEx, que expõe uma Distribuição LogNormal estatisticamente relevante. As Taxas de Produção anuais são aleatoriamente selecionadas a partir de distribuições históricas de reservatórios semelhantes. O preço do Brent, é estimado num processo de Reversão à Média com difusão de Saltos...

The frequency domain causality analysis between energy consumption and income in the United States

Tiwari,Aviral Kumar
Fonte: Faculdade de Economia, Administração e Contabilidade de Ribeirão Preto da Universidade de São Paulo Publicador: Faculdade de Economia, Administração e Contabilidade de Ribeirão Preto da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2014 Português
Relevância na Pesquisa
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We investigated Granger-causality in the frequency domain between primary energy consumption/electricity consumption and GDP for the US by employing approach of Lemmens et al. (2008) and covering the period of January, 1973 to December, 2008. We found that causal and reverse causal relations between primary energy consumption and GDP and electricity consumption and GDP vary across frequencies. Our unique contribution in the existing literature lies in decomposing the causality on the basis of time horizons and demonstrating bidirectional the short-run, the medium-run and the long-run causality between GDP and primary energy consumption/electricity consumption and thus providing evidence for the feedback hypothesis. These results have important implications for the US for planning of the short, the medium and the long run energy and economic growth related policies.

Recombinant extracellular domain of the three major subunits of GABAA receptor show comparable secondary structure and benzodiazepine binding properties

Shi, Haifeng; Tsang, Shui Ying; Tse, Man Kit; Xu, Zhiwen; Xue, Hong
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: Artigo de Revista Científica
Publicado em /11/2003 Português
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The three most widely expressed subunits of the GABAA receptor are α1, β2, and γ2 subunits, and the major isoform in the human brain is a pentameric receptor composed of 2α12β21γ2. Previously, we overexpressed the extracellular domain Q28-R248 of GABAA receptor α1 subunit. In the present study, the homologous extracellular domains Q25-G243 of GABAA receptor β2 subunit and Q40-G273 of γ2 subunit were also obtained through overexpression in Escherichia coli. Successful production of recombinant β2 and γ2 subunit receptor protein domains facilitates the comparison of structural and functional properties of the three subunits. To this end, the secondary structures of the three fragments were measured using CD spectroscopy and the β-strand contents calculated to be >30%, indicating a β-rich structure for all three fragments. In addition, the benzodiazepine (BZ)-binding affinity of the recombinant fragments were measured using fluorescence polarization to be 2.16 μM, 3.63 μM, and 1.34 μM for the α1, β2, and γ2 subunit fragments, respectively, indicating that all three homomeric assemblies, including that of the β2 subunit, generally not associated with BZ binding, can bind BZ in the micromolar range. The finding that the BZ binding affinity of these recombinant domains was highest for the γ2 subunit and lowest for the β2 subunit is consistent with results from previous binding studies using hetero-oligomeric receptors. The present results exemplify the effective approach to characterize and compare the three major subunits of the GABAA receptor...

Polyglutamine Aggregate Structure In Vitro and In Vivo; New Avenues for Coherent Anti-Stokes Raman Scattering Microscopy

Perney, Nicolas M.; Braddick, Lucy; Jurna, Martin; Garbacik, Erik T.; Offerhaus, Herman L.; Serpell, Louise C.; Blanch, Ewan; Holden-Dye, Lindy; Brocklesby, William S.; Melvin, Tracy
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 20/07/2012 Português
Relevância na Pesquisa
17.52%
Coherent anti-Stokes Raman scattering (CARS) microscopy is applied for the first time for the evaluation of the protein secondary structure of polyglutamine (polyQ) aggregates in vivo. Our approach demonstrates the potential for translating information about protein structure that has been obtained in vitro by X-ray diffraction into a microscopy technique that allows the same protein structure to be detected in vivo. For these studies, fibres of polyQ containing peptides (D2Q15K2) were assembled in vitro and examined by electron microscopy and X-ray diffraction methods; the fibril structure was shown to be cross β-sheet. The same polyQ fibres were evaluated by Raman spectroscopy and this further confirmed the β-sheet structure, but indicated that the structure is highly rigid, as indicated by the strong Amide I signal at 1659 cm−1. CARS spectra were simulated using the Raman spectrum taking into account potential non-resonant contributions, providing evidence that the Amide I signal remains strong, but slightly shifted to lower wavenumbers. Combined CARS (1657 cm−1) and multi-photon fluorescence microscopy of chimeric fusions of yellow fluorescent protein (YFP) with polyQ (Q40) expressed in the body wall muscle cells of Caenorhabditis elegans nematodes (1 day old adult hermaphrodites) revealed diffuse and foci patterns of Q40-YFP that were both fluorescent and exhibited stronger CARS (1657 cm−1) signals than in surrounding tissues at the resonance for the cross β-sheet polyQ in vitro.

rpoD Gene Pyrosequencing for the Assessment of Pseudomonas Diversity in a Water Sample from the Woluwe River

Sánchez, David; Matthijs, Sandra; Gomila, Margarita; Tricot, Catherine; Mulet, Magdalena; García-Valdés, Elena; Lalucat, Jorge
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /08/2014 Português
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16.83%
A water sample from a noncontaminated site at the source of the Woluwe River (Belgium) was analyzed by culture-dependent and -independent methods. Pseudomonas isolates were identified by sequencing and analysis of the rpoD gene. Culture-independent methods consisted of cloning and pyrosequencing of a Pseudomonas rpoD amplicon from total DNA extracted from the same sample and amplified with selective rpoD gene primers. Among a total of 14,540 reads, 6,228 corresponded to Pseudomonas rpoD gene sequences by a BLAST analysis in the NCBI database. The selection criteria for the reads were sequences longer than 400 bp, an average Q40 value greater than 25, and >85% identity with a Pseudomonas species. Of the 6,228 Pseudomonas rpoD sequences, 5,345 sequences met the established criteria for selection. Sequences were clustered by phylogenetic analysis and by use of the QIIME software package. Representative sequences of each cluster were assigned by BLAST analysis to a known Pseudomonas species when the identity with the type strain was greater than or equal to 96%. Twenty-six species distributed among 12 phylogenetic groups or subgroups within the genus were detected by pyrosequencing. Pseudomonas stutzeri, P. moraviensis, and P. simiae were the only cultured species not detected by pyrosequencing. The predominant phylogenetic group within the Pseudomonas genus was the P. fluorescens group...

Identification of a selective glucocorticoid receptor ligand for the treatment of chronic inflammation in type 2 diabetes mellitus

TAN, HAIFENG; WANG, WEI; YIN, XIANGANG; LI, YAO; YIN, RUI
Fonte: D.A. Spandidos Publicador: D.A. Spandidos
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.88%
The present study aimed to identify a new selective glucocorticoid receptor (GR) ligand for the treatment of chronic inflammation in type 2 diabetes mellitus. The IN Cell Analyzer 1000 platform was employed to screen for compounds that may promote GR nuclear translocation. A mammalian two-hybrid system and transactivation assay-were used to analyze the selected GR ligands and evaluate their activities for GR transcription and the recruitment of co-activators. A novel selective GR ligand, compound Q40, was identified that was able to promote GR nuclear translocation in a short period of time. It increased the ability of GR to recruit co-activators in a concentration-dependent manner, but had no positive effect on GR transcriptional activity. In conclusion, an increase in the expression levels of gluconeogeneic genes, induced by the transcriptional activation of GR, is the predisposing factor most commonly associated with the side-effects of glucocorticoids. The results suggest that compound Q40 is a ligand of the GR and exerts an agonistic action on the recruitment of co-activators without sugar dysmetabolism-related side-effects. Thus, compound Q40 has the potential to be used as an anti-inflammatory adjuvant therapy with minimal side-effects in patients with type 2 diabetes mellitus.

The role of information for energy efficiency in the residential sector

RAMOS, Ana; GAGO, Alberto; LABANDEIRA, Xavier; LINARES, Pedro
Fonte: Instituto Universitário Europeu Publicador: Instituto Universitário Europeu
Tipo: Trabalho em Andamento Formato: application/pdf; digital
Português
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In spite of the large potential and existing efforts to foster energy efficiency in the residential sector, much remains to be achieved. This may be partially due to the many barriers and market failures faced by energy efficiency, which are even greater in the residential sector. In particular, informational failures seem to be pervasive and relevant in this area. Addressing these issues requires specific policy instruments and strategies. This paper reviews the empirical evidence on the effectiveness of such instruments, focusing on energy certificates, feedback programs, and energy audits. Results show that energy certificates and feedback programs can be effective, but only if they are carefully designed. Yet energy audits seem to have little effect on efficiency. In addition, the paper points out the large potential for new instruments as well as combinations of existing ones.

Pricing forward contracts in power markets by the certainty equivalence principle: Explaining the sign of the market risk premium

Benth, Fred Espen; Cartea, Álvaro; Kiesel, Rüdiger
Fonte: Elsevier Publicador: Elsevier
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article Formato: application/pdf
Publicado em /10/2008 Português
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In this paper we provide a framework that explains how the market risk premium, defined as the difference between forward prices and spot forecasts, depends on the risk preferences of market players and the interaction between buyers and sellers. In commodities markets this premium is an important indicator of the behavior of buyers and sellers and their views on the market spanning between short-term and long-term horizons. We show that under certain assumptions it is possible to derive explicit solutions that link levels of risk aversion and market power with market prices of risk and the market risk premium. We apply our model to the German electricity market and show that the market risk premium exhibits a term structure which can be explained by the combination of two factors. Firstly, the levels of risk aversion of buyers and sellers, and secondly, how the market power of producers, relative to that of buyers, affects forward prices with different delivery periods

Error analysis of idealized nanopore sequencing

O'Donnell, Christopher R.; Wang, Hongyun; Dunbar, William B.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/2013 Português
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This numerical study provides an error analysis of an idealized nanopore sequencing method in which ionic current measurements are used to sequence intact single-stranded DNA in the pore, while an enzyme controls DNA motion. Examples of systematic channel errors when more than one nucleotide affects the current amplitude are detailed, which if present will persist regardless of coverage. Absent such errors, random errors associated with tracking through homopolymer regions are shown to necessitate reading known sequences (E. coli K-12) at least 140 times to achieve 99.99% accuracy (Q40). By exploiting the ability to reread each strand at each pore in an array, arbitrary positioning on an error rate vs. throughput tradeoff curve is possible if systematic errors are absent, with throughput governed by the number of pores in the array and the enzyme turnover rate.

The threshold for polyglutamine-expansion protein aggregation and cellular toxicity is dynamic and influenced by aging in Caenorhabditis elegans

Morley, James F.; Brignull, Heather R.; Weyers, Jill J.; Morimoto, Richard I.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
Português
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16.83%
Studies of the mutant gene in Huntington's disease, and for eight related neurodegenerative disorders, have identified polyglutamine (polyQ) expansions as a basis for cellular toxicity. This finding has led to a disease hypothesis that protein aggregation and cellular dysfunction can occur at a threshold of approximately 40 glutamine residues. Here, we test this hypothesis by expression of fluorescently tagged polyQ proteins (Q29, Q33, Q35, Q40, and Q44) in the body wall muscle cells of Caenorhabditis elegans and show that young adults exhibit a sharp boundary at 35–40 glutamines associated with the appearance of protein aggregates and loss of motility. Surprisingly, genetically identical animals expressing near-threshold polyQ repeats exhibited a high degree of variation in the appearance of protein aggregates and cellular toxicity that was dependent on repeat length and exacerbated during aging. The role of genetically determined aging pathways in the progression of age-dependent polyQ-mediated aggregation and cellular toxicity was tested by expressing Q82 in the background of age-1 mutant animals that exhibit an extended lifespan. We observed a dramatic delay of polyQ toxicity and appearance of protein aggregates. These data provide experimental support for the threshold hypothesis of polyQ-mediated toxicity in an experimental organism and emphasize the importance of the threshold as a point at which genetic modifiers and aging influence biochemical environment and protein homeostasis in the cell.

Proteins in aggregates functionally impact multiple neurodegenerative disease models by forming proteasome-blocking complexes

Ayyadevara, Srinivas; Balasubramaniam, Meenakshisundaram; Gao, Yuan; Yu, Li-Rong; Alla, Ramani; Shmookler Reis, Robert
Fonte: BlackWell Publishing Ltd Publicador: BlackWell Publishing Ltd
Tipo: Artigo de Revista Científica
Português
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17.88%
Age-dependent neurodegenerative diseases progressively form aggregates containing both shared components (e.g., TDP-43, phosphorylated tau) and proteins specific to each disease. We investigated whether diverse neuropathies might have additional aggregation-prone proteins in common, discoverable by proteomics. Caenorhabditis elegans expressing unc-54p/Q40::YFP, a model of polyglutamine array diseases such as Huntington's, accrues aggregates in muscle 2–6 days posthatch. These foci, isolated on antibody-coupled magnetic beads, were characterized by high-resolution mass spectrometry. Three Q40::YFP-associated proteins were inferred to promote aggregation and cytotoxicity, traits reduced or delayed by their RNA interference knockdown. These RNAi treatments also retarded aggregation/cytotoxicity in Alzheimer's disease models, nematodes with muscle or pan-neuronal Aβ1–42 expression and behavioral phenotypes. The most abundant aggregated proteins are glutamine/asparagine-rich, favoring hydrophobic interactions with other random-coil domains. A particularly potent modulator of aggregation, CRAM-1/HYPK, contributed < 1% of protein aggregate peptides, yet its knockdown reduced Q40::YFP aggregates 72–86% (P < 10−6). In worms expressing Aβ1–42...

Costos humanos de la era nuclear

Delgado Ramos, Gian Carlo; Martínez Negrete, Marco Antonio; Rincón Mejía, Eduardo; Salas Mar, Bernardo
Fonte: Radio UNAM Publicador: Radio UNAM
Tipo: Audio; NonPeerReviewed Formato: audio/mpeg
Publicado em 31/03/2011 Português
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Los accidentes nucleares han causado severos daños a la humanidad, y aun así se sigue apostando por el desarrollo de este tipo de energía, tanto en uso bélico, como en materia de producción. Son muchos los análisis que existen al respecto con el propósito de crear conciencia. Acerca de esto fue la presente emisión.

Sin energía el reto de los combustibles fósiles. El paradigma energético

Delgado Ramos, Gian Carlo
Fonte: Radio UNAM Publicador: Radio UNAM
Tipo: Audio; NonPeerReviewed Formato: audio/mpeg
Publicado em 21/05/2009 Português
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16.83%
El título de la presente emisión, es el de la publicación mas reciente de nuestro invitado, es entonces que la entrevista giró en torno a la presentación de dicho material.

¿Qué debemos esperar con la siguiente reforma energética para PEMEX y la CFE?

Hernández Haddad, Humberto
Fonte: Instituto de Investigaciones Económicas y Radio Universidad Nacional Autónoma de México Publicador: Instituto de Investigaciones Económicas y Radio Universidad Nacional Autónoma de México
Tipo: Audio; NonPeerReviewed Formato: audio/mpeg
Publicado em 23/05/2013 Português
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Dentro de la presente emisión, el invitado habló acerca de las consecuencias de la Reforma Energética para ambas paraestatales. Al hacerlo abordó el tema energético sobre todo en materia de infraestructura y el Plan Nacional de Desarrollo publicado recientemente en Diario Oficial de la Federación.

Shale gas en México

Barbosa Cano, Fabio Erazo; Ortuño Arzate, Salvador; Garaicochea Petrirena, Francisco
Fonte: Radio Universidad Nacional Autónoma de México. Instituto de Investigaciones Económicas Publicador: Radio Universidad Nacional Autónoma de México. Instituto de Investigaciones Económicas
Tipo: Audio; NonPeerReviewed Formato: audio/mpeg
Publicado em 21/06/2012 Português
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Dentro de la presente emisión se realizó un análisis de las probabilidades de la utilización del shale gas o gas lutitas. Al realizar dicho análisis se informa acerca de lo que es este gas natural y de sus efectos.

Diversity and Security in UK Electricity Generation: The Influence of Low Carbon Objectives

Grubb, Michael; Butler, Lucy; Sinden, Graham
Fonte: Universidade de Cambridge Publicador: Universidade de Cambridge
Formato: 1006237 bytes; application/pdf; application/pdf
Português
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We explore the relationship between low carbon objectives and the strategic security of electricity in the context of the UK Electricity System. We consider diversity of fuel source mix to represent one dimension of security - robustness against interruptions of any one source - and apply two different diversity indices to the range of electricity system scenarios produced by the UK government and independent researchers. Using data on wind generation we also consider whether a second dimension of security - the reliability of generation availability - is compromised by intermittency of renewable generation. Our results show that low carbon objectives are uniformly associated with greater long-term diversity in UK electricity. We discuss reasons for this result, explore sensitivities, and briefly discuss possible policy instruments associated with diversity and their limitations.

Using EPECs to model bilevel games in restructured electricity markets with locational prices

Hu, Xinmin; Ralph, Daniel
Fonte: Universidade de Cambridge Publicador: Universidade de Cambridge
Formato: 309861 bytes; application/pdf; application/pdf
Português
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CWPE0619 (EPRG0602) Xinmin Hu and Daniel Ralph (Feb 2006) Using EPECs to model bilevel games in restructured electricity markets with locational prices We study a bilevel noncooperative game-theoretic model of electricity markets with locational marginal prices. Each player faces a bilevel optimization problem that we remodel as a mathematical program with equilibrium constraints, MPEC. This gives an EPEC, equilibrium problem with equilibrium constraints. We establish sufficient conditions for existence of pure strategy Nash equilibria for this class of bilevel games and give some applications. We show by examples the effect of network transmission limits, i.e. congestion, on existence of equilibria. Then we study, for more general EPECs, the weaker pure strategy concepts of local Nash and Nash stationary equilibria. We model the latter via complementarity problems, CPs. Finally, we present numerical examples of methods that attempt to find local Nash or Nash stationary equilibria of randomly generated electricity market games. The CP solver PATH is found to be rather effective in this context.