Search results for "Copula"
showing 10 items of 59 documents
A new hybrid method to improve the ultra-short-term prediction of LOD
2019
Accurate, short-term predictions of Earth orientation parameters (EOP) are needed for many real-time applications including precise tracking and navigation of interplanetary spacecraft, climate forecasting, and disaster prevention. Out of the EOP, the LOD (length of day), which represents the changes in the Earth’s rotation rate, is the most challenging to predict since it is largely affected by the torques associated with changes in atmospheric circulation. In this study, the combination of Copula-based analysis and singular spectrum analysis (SSA) method is introduced to improve the accuracy of the forecasted LOD. The procedure operates as follows: First, we derive the dependence structur…
Polyandrous females produce sons that are successful at post-copulatory competition.
2014
Some of the genetic benefit hypotheses put forward to explain multiple male mating (polyandry) predict that sons of polyandrous females will have an increased competitive ability under precopulatory or post-copulatory competition via paternally inherited traits, such as attractiveness or fertilization efficiency. Here, we tested these predictions by comparing the competitive ability of sons of experimentally monandrous and polyandrous female bank voles (Myodes glareolus), while controlling for potential material and maternal effects. In female choice experiments, we found no clear preference for sons of either monandrous or polyandrous mothers. Moreover, neither male type was dominant over …
Assessing the effectiveness of Byssochlamys nivea and Scopulariopsis brumptii in pentachlorophenol removal and biological control of two Phytophthora…
2016
Bioremediation and biological-control by fungi have made tremendous strides in numerous biotechnology applications. The aim of this study was to test Byssochlamys nivea and Scopulariopsis brumptii in sensitivity and degradation to pentachlorophenol (PCP) and in biological-control of Phytophthora cinnamomi and Phytophthora cambivora. B. nivea and S. brumptii were tested in PCP sensitivity and degradation in microbiological media while the experiments of biological-control were carried out in microbiological media and soil. The fungal strains showed low PCP sensitivity at 12.5 and 25 mg PCP L(-1) although the hyphal size, fungal mat, patulin, and spore production decreased with increasing PCP…
Pair-bonding in birds and the active role of females: a critical review of the empirical evidence.
2000
Over the recent years the role of females in maintaining or breaking the pair-bond in socially monogamous birds has received growing attention. Here, we review the overall evidence for a direct and predominant role of female behaviour in initiating or preventing divorce and its relevance for the understanding of both interspecific and intraspecific variation in divorce rate in monogamous bird species. The evidence is so far limited to a few species. We discuss the relevance of some alternative explanations and confounding factors. We conclude that the possible predominance of females in both initiating divorce or limiting its occurrence deserves further consideration. Future studies should …
Probabilistic characterization of flood hazard using bivariate analysis based on copulas
2014
This study presents an innovative approach to obtain flood hazard maps where hydrological input (synthetic flood design event) to a 2D hydraulic model has been defined by generating flood peak discharges and volumes from a bivariate statistical analysis, through the use of copulas. Synthetic hydrographs were generated by means two different approaches: an indirect one, where rainfall were generated by a stochastic bivariate rainfall generator to be entered a distributed conceptual rainfall-runoff model that consisted of a soil moisture routine and a flow routing routine; and a direct one, where stochastic generation of flood peaks and flow volumes have been obtained via copulas, which descr…
Nomi predicativi. Articoli, verbi supporto, finiture sintattiche
2022
The idea that the verb is always the sentence core (verbocentrism) has a long history. In the last century a number of researchers started doubting it. This book shows some of the reasons why verbs should not some times be considered the kernel of a sentence. The investigated constructions come from Italian and English and have properties which clearly derive from the post-verbal noun. Some new arguments are presented, in relation to copulative constructions, support verb constructions, and serial verbs. The overall picture which these investigations produce show first how weak verbocentrism is and, second, how verbocentrism can be easily overcome.
Polar motion prediction using the combination of SSA and Copula-based analysis
2018
The real-time estimation of polar motion (PM) is needed for the navigation of Earth satellite and interplanetary spacecraft. However, it is impossible to have real-time information due to the complexity of the measurement model and data processing. Various prediction methods have been developed. However, the accuracy of PM prediction is still not satisfactory even for a few days in the future. Therefore, new techniques or a combination of the existing methods need to be investigated for improving the accuracy of the predicted PM. There is a well-introduced method called Copula, and we want to combine it with singular spectrum analysis (SSA) method for PM prediction. In this study, first, we…
Operational risk in bank governance and control: How to save capital requirement through a risk transfer strategy. Evidences from a simulated case st…
2015
Operational risk management in banking has assumed such importance during the last decade. It has become increasingly important to measure, manage, and assess the impact of operational risk in the economics of banking. The purpose of this paper is to demonstrate how an effective operational risk management provides mitigating effects on capital-at-risk in banking. The paper provides evidences that an implementation of an operational risk transfer strategy reduces bank capital requirement. The paper adopts the loss distribution approach, the Monte Carlo simulation, and copula methodologies to estimate the regulatory capital and simulate an operational risk transfer strategy in banking.
De las copulativas identificativas a las justificativas con 'es que'
2021
Las construcciones encabezadas por es que se utilizan, entre otras cosas, para justificar lo dicho, el acto de habla realizado, la réplica que se introduce, etc. Estas construcciones justificativas se formaron a partir de copulativas identificativas del tipo lo que ocurre / el problema es que... en contextos en los que no se explicita el sujeto y emerge una inferencia de causalidad. La construcción empieza a documentarse en el siglo xvi e inicialmente se usa para introducir una explicación o una justificación de lo dicho. A este significado se añade muy pronto un valor contrastivo, sobre todo en contextos de réplica, y más tarde, coincidiendo con la gran difusión de la construcción en la le…
Estimation of flood design hydrographs using bivariate analysis (copula) and distributed hydrological modelling
2014
Abstract. In this paper a procedure to derive Flood Design Hydrographs (FDH) using a bivariate representation of rainfall forcing (rainfall duration and intensity) using copulas, which describe and model the correlation between these two variables independently of the marginal laws involved, coupled with a distributed rainfall-runoff model is presented. Rainfall-runoff modelling for estimating the hydrological response at the outlet of a watershed used a conceptual fully distributed procedure based on the soil conservation service – curve number method as excess rainfall model and a distributed unit hydrograph with climatic dependencies for the flow routing. Travel time computation, based o…