Search results for "A* algorithm"
showing 10 items of 2538 documents
Conditions for the spread of conspicuous warning signals: A numerical model with novel insights
2007
The initial evolution of conspicuous warning signals presents an evolutionary problem because selection against rare conspicuous signals is presumed to be strong, and new signals are rare when they first arise. Several possible solutions have been offered to solve this apparent evolutionary paradox, but disagreement persists over the plausibility of some of the proposed mechanisms. In this paper, we construct a deterministic numerical simulation model that allows us to derive the strength of selection on novel warning signals in a wide range of biologically relevant situations. We study the effects of predator psychology (learning, rate of mistaken attacks, and neophobia) on selection. We a…
SELECTING HERB-RICH FOREST NETWORKS TO PROTECT DIFFERENT MEASURES OF BIODIVERSITY
2001
Data on vascular plants of herb-rich forests in Finland were used to compare the efficiency of reserve selection methods in representing three measures of biodiversity: species richness, phylogenetic diversity, and restricted-range diversity. Comparisons of reserve selection methods were carried out both with and without consideration of the existing reserve system. Our results showed that the success of a reserve network of forests in representing different measures of biodiversity depends on the selection procedure, selection criteria, and data set used. Ad hoc selection was the worst option. A scoring procedure was generally more efficient than maximum random selection. Heuristic methods…
Venture Capitalists' Decision to Syndicate.
2006
International audience; Financial theory, access to deal flow, selection, and monitoring skills are used to explain syndication in venture capital firms in six European countries. In contrast with U.S. findings, portfolio management motives are more important for syndication than individual deal management motives. Risk sharing, portfolio diversification, and access to larger deals are more important than selection and monitoring of deals. This holds for later stage and for early stage investors. Value adding is a stronger motive for syndication for early stage investors than for later stage investors, however. Nonlead investors join syndicates for the selection and value-adding skills of t…
Selection by committee: Anonymity and gratitude
2018
Abstract What kind of candidate is selected into a job when the principal has to appoint a committee to measure the candidates’ ability and select a winner? We find that if the committee takes into account the candidate’s gratitude towards them, a candidate with less than first best ability will be selected. A relevant exception may occur if the first best is the overall best candidate. First best selection is always achieved if the committee is anonymous to the candidates. If the committee is not detached enough from the candidates then delegation fares even worse than random selection.
Does Firm Size Affect Self-selection and Learning-by-Exporting?
2010
The trade literature has long discussed the existence of some benefits attributed to exporting, among others, the improvement of firm productivity. This paper examines whether firm size plays a role in this supposedly favourable relationship between exporting and total factor productivity (TFP). To examine this, we investigate, separately for large and small firms, whether firms starting to export perform better ex ante (self-selection) than non-exporting firms and, conditional on this fact, if they are also more productive ex post (learning-by-exporting). With this purpose, we use both stochastic dominance and matching techniques. The dataset is a representative sample of Spanish manufactu…
A problem-adjusted genetic algorithm for flexibility design
2013
Many present markets for goods and services have highly volatile demand due to short life cycles and strong competition in saturated environments. Determination of capacity levels is difficult because capacities often need to be set long before demand realizes. In order to avoid capacity-demand mismatches, operations managers employ mix-flexible resources which allow them to shift excess demands to unused capacities. The Flexibility Design Problem (FDP) models the decision on the optimal configuration of a flexible (manufacturing) network. FDP is a difficult stochastic optimization problem, for which traditional exact approaches are not able to solve but the smallest instances in reasonable…
A naïve approach to speed up portfolio optimization problem using a multiobjective genetic algorithm
2012
a b s t r a c t Genetic algorithms (GAs) are appropriate when investors have the objective of obtaining mean-variance (VaR) efficient frontier as minimising VaR leads to non-convex and non-differential risk-return optimisation problems. However GAs are a time-consuming optimisation technique. In this paper, we propose to use a naive approach consisting of using samples split by quartile of risk to obtain complete efficient frontiers in a reasonable computation time. Our results show that using reduced problems which only consider a quartile of the assets allow us to explore the efficient frontier for a large range of risk values. In particular, the third quartile allows us to obtain efficie…
Compression Methods for Microclimate Data Based on Linear Approximation of Sensor Data
2019
Edge computing is currently one of the main research topics in the field of Internet of Things. Edge computing requires lightweight and computationally simple algorithms for sensor data analytics. Sensing edge devices are often battery powered and have a wireless connection. In designing edge devices the energy efficiency needs to be taken into account. Pre-processing the data locally in the edge device reduces the amount of data and thus decreases the energy consumption of wireless data transmission. Sensor data compression algorithms presented in this paper are mainly based on data linearity. Microclimate data is near linear in short time window and thus simple linear approximation based …
ES konkurences tiesību regulējums un pierādīšanas standarts aizliegtu vienošanās lietās, kurās izmantota cenu veidošanas algoritmu programmatūra
2021
Eiropas Komisija ir paudusi uzskatu, ka Eiropas Savienībā tiesību regulējumam ir jābūt vienādam, “likvidējot jebkādu mākslīgu nošķīrumu starp tradicionālo un digitālo tirgu”. Šis maģistra darbs pētī jautājumu, vai Eiropas konkurences tiesības paredz iespēju pierādīt aizliegtas vienošanās, karteļa esamību tad, ja tiek izmantoti viedie cenu algoritmi un nav pierādījumu par tradicionālu komunikāciju starp tirgus dalībniekiem. Analizējot judikatūru par LESD 101 (1) punktu, īpaši pievēršoties lietām, kurās pierādījumi vākti e-vidē, tiek secināts ar kādiem ierobežojumiem būtu jāsastopas izmeklējošajai iestādei, piemēram, EK, mēģinot pierādīt tāda karteļa esamību, kas darbojas uz algoritmu pamata.…
Enhanced flexible algorithm for the optimization of slot filling factors in electrical machines †
2020
The continuous development in the field of industrial automation and electric mobility has led to the need for more efficient electrical machines with a high power density. The improvement of electrical machines’ slot filling factors is one of the measures to satisfy these requirements. In recent years, this topic has aroused greater interest in the industrial sector, since the evolution of the winding technological manufacturing processes allows an economically sustainable realization of ordered winding arrangements, rather than random ones. Moreover, the manufacture of electrical machines’ windings must be preceded by an accurate design phase in which it is possible to evaluate the maximu…