Search results for "Minimum"
showing 10 items of 327 documents
Minimum power losses by using droop coefficients regulation method with voltage and frequency constraints in islanded microgrids
2018
In this paper, a droop coefficients regulation methodology is proposed for an islanded microgrid to optimize the power losses. Based on the P-f and Q-V relations to adjust the droop coefficients at every loading condition, the optimized operating set point generates minimum power losses operation while satisfying the constraints of voltage and frequency limitation. A 9-bus case study is here implemented to show the effectiveness of this new approach as well as the improved operation quality of the system.
In vitro activities of antimicrobial agents against Candida species
1999
Objective. Antimicrobial mouthrinses may represent a valid alternative to topical antifungal agents. However, the action of antimicrobials could be affected by the different ingredients incorporated into mouthrinse products. The purpose of the present study was to investigate the in vitro antifungal and fungicidal activities of antimicrobials alone. Study Design. A broth macrodilution method was used to determine the minimum inhibitory concentration of 4 antimicrobial agents against Candida species. Minimum fungicidal concentration was also determined. Results. All antimicrobials showed antifungal activity against all tested organisms, but cetylpyridinium chloride received significantly low…
Habitat preferences of Bonelli's Eagles Aquila fasciata in Sicily
2012
Capsule For breeding, areas dominated by extensive agricultural and rugged Mediterranean landscapes are preferred; maintenance of habitat heterogeneity and extensive agriculture are key for the conservation of this eagle. Aims To model breeding habitat preferences of Bonelli's Eagles Aquila fasciata in Sicily, where the last viable population still remains in Italy, in order to identify the most important habitats for conservation. Methods Pairs were monitored between 1990 and 2010. A case-control design through glms was used at two spatial scales: landscape and home-range. Variables included topographic, climatic, land-use, road and descriptors of habitat heterogeneity. Information-based c…
Local Spatio-Temporal Log-Gaussian Cox Processes for seismic data analysis
2022
We propose a local version of the spatio-temporal log-Gaussian Cox processes (LGCPs) employing the Local Indicators of Spatio-Temporal Association (LISTA) functions into the minimum contrast procedure to obtain space as well as time-varying parameters. We resort to the joint minimum contrast method fitting method to estimate the set of second-order parameters for the class of Spatio-Temporal LGCPs. We employ the proposed methodology to analyse real seismic data occurred Greece between 2004 and 2015.
Evaluation of antifungal activity of three essential oils against selected isolates of Penicillium, Purpureocillium and Acremonium
2018
Storage is a critical process of food production because incorrect conditions during this process lead to the growth of economic costs caused by material loss. It is important to maintain adequate microbiological purity of storage areas. The development of microbes present in warehouses may lead to secondary contamination of stored materials and reduce their quality. The aim of the study was to evaluate the effect of essential oils on the growth of Acremonium strictum , Penicillium citrinum, Penicillium expansum and Purpureocillium lilacinum . Fungal strains were isolated from the food warehouse. Studies on the influence of selected mix of phenolic substances were performed using three comm…
Perception of Key Management Contribution Factos to the Future Development of the Hotel Industry: A Comparative Analysis of British/Irish & Spani…
2015
For Spain the importance of tourism both national and international, does not hold any doubts for those versed in the subject. A few general figures suffice to illustrate this. In 1991 a total of 53.5 million people visited Spain, a slightly higher number than the 52 million which did in 1990, and slightly less than the 52 million of the previous year, this meant a revenue of 19,004 million dollars in 1991, 18,593 million dollars in 1990 and 16,174 million dollars in 1989. Tourism achieved a participation in the Gross Domestic Product of 8.74% in 1989. In the last few years 85% of tourists have been from Portugal, followed by West Germany with 13% and the U.K. with 12%, as the major contrib…
Pricing the Option to Surrender in Incomplete Markets
2010
New international accounting standards require insurers to reflect the value of embedded options and guarantees in their products. Pricing techniques based on the Black and Scholes paradigm are often used; however, the hypotheses underneath this model are rarely met. We propose a framework that encompasses the most known sources of incompleteness. We show that the surrender option, joined with a wide range of claims embedded in insurance contracts, can be priced through our tool, and deliver hedging portfolios to mitigate the risk arising from their positions. We provide extensive empirical analysis to highlight the effect of incompleteness on the fair value of the option.
Strategic sharing of a costly network
2012
We study minimum cost spanning tree problems for a set of users connected to a source. Prim’s algorithm provides a way of finding the minimum cost tree mm. This has led to several definitions in the literature, regarding how to distribute the cost. These rules propose different cost allocations, which can be understood as compensations and/or payments between players, with respect to the status quo point: each user pays for the connection she uses to be linked to the source. In this paper we analyze the rationale behind a distribution of the minimum cost by defining an a priori transfer structure. Our first result states the existence of a transfer structure such that no user is willing to …
European Natural Gas Seasonal Effects on Futures Hedging
2015
Abstract This paper is the first to discuss the design of futures hedging strategies in European natural gas markets (NBP, TTF and Zeebrugge). A common feature of energy prices is that conditional mean and volatility are driven by seasonal trends due to weather, demand, and storage level seasonalities. This paper follows and extends the Ederington and Salas (2008) framework and considers seasonalities in mean and volatility when minimum variance hedge ratios are computed. Our results show that hedging effectiveness is much higher when the seasonal pattern in spot price changes is approximated with lagged values of the basis (futures price minus spot price). This fact remains true for short …
How does fiscal policy react to wealth composition and asset prices?
2012
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