Transforming Normal Programs by Replacement

The replacement transformation operation, already defined in [28], is studied wrt normal programs. We give applicability conditions able to ensure the correctness of the operation wrt Fitting's and Kunen's semantics. We show how replacement can mimic other transformation operations such as thinning, fattening and folding, thus producing applicability conditions for them too. Furthermore we characterize a transformation sequence for which the preservation of Fitting's and Kunen's semantics is ensured

The Value of Integrative Risk Management for Insurance Products with Guarantees

Insurers increasingly offer policies that converge with the products of the capital markets, and they face a need for integrative asset and liability management strategies. In this paper we show that an integrative approach -- based on scenario optimization modeling -- adds value to the risk management process, when compared to traditional methods. Empirical analysis with products offered by the Italian insurance industry are presented. The results have implications for the design of competitive insurance policies, and some examples are analyzed.

Asset and Liability Modeling for Participating Policies with Guarantees

We study the problem of asset and liability management of participating insurance policies with guarantees. We develop a scenario optimization model for integrative asset and liability management, analyze the tradeoffs in structuring such policies, and study alternative choices in funding them. The nonlinearly constrained optimization model can be linearized through closed form solutions of the dynamic equations. Thus large-scale problems are solved with standard methods. We report on an empirical analysis of policies offered by Italian insurers. The optimized model results are in general agreement with current industry practices. However, some inefficiencies are identified and potential improvements are highlighted.

Feeding, Reproduction, and Development of the Red Palm Mite (Acari: Tenuipalpidae) on Selected Palms and Banana Cultivars in Quarantine

ABSTRACT The red palm mite, Raoiella indica Hirst, an important pest of coconut, banana, and date palms is a new invasive pest in the Western Hemisphere. The red palm mite (RPM) has been observed attacking bananas and plantains in Dominica and in Florida (M. A. Hoy, A. Cocco, personal observation). In order to develop an efficient method to rear the RPM in quarantine for a classical biological control project, several banana and plantain varieties were tested as hosts for the RPM. Bananas are more desirable than coconut (a favored host plant) because bananas are easier to rear in small cages and will produce new shoots quickly after pruning. Red palm mite females did not establish on the banana and plantain varieties (Dwarf Cavendish, Dwarf Nino, Gran Nain, Dwarf Zan Moreno, Dwarf Green, Truly Tiny, Musa sumatrana × Gran Nain, Dwarf Puerto Rican, Rose, Nang Phaya, Misi Luki, Manzano, Lady Finger, Glui Kai, and Ebun Musak) of leaf discs tested, but they established on coconut leaf discs. The mites could no..

Probing Low Energy Neutrino Backgrounds with Neutrino Capture on Beta Decaying Nuclei

We study the interaction of low energy neutrinos on nuclei that spontaneously undergo beta decay showing that the product of the cross section times neutrino velocity takes values as high as 10^{-42} cm^2 c for some specific nuclei that decay via allowed transitions. The absence of energy threshold and the value of the cross section single out these processes as a promising though very demanding approach for future experiments aimed at a direct detection of low energy neutrino backgrounds such as the cosmological relic neutrinos.Comment: Includes a discussion of local relic neutrino density effect on neutrino capture rate. Accepted for publication in JCA

On Safe Folding

In [3] a general fold operation has been introduced for definite programs wrt computed answer substitution semantics. It differs from the fold operation defined by Tamaki and Sato in [26,25] because its application does not depend on the transformation history. This paper extends the results in [3] by giving a more powerful sufficient condition for the preservation of computed answer substitutions. Such a condition is meant to deal with the critical case when the atom introduced by folding depends on the clause to which the fold applies. The condition compares the dependency degree between the fonding atom and the folded clause, with the semantic delay between the folding atom and the ones to be folded. The result is also extended to a more general replacement operation, by showing that it can be decomposed into a sequence of definition, general folding and unfolding operations

How to enhance crop production and nitrogen fluxes? A result-oriented scheme to evaluate best agri-environmental measures in Veneto Region, Italy

The cost-effectiveness of adopting agri-environmental measures (AEMs) in Europe, which combine agricultural productions with reduced N losses, is debated due to poorly targeted site-specific funding that is allocated regardless of local variability. An integrated DAYCENT model-GIS platform was developed combining pedo-climatic and agricultural systems information. The aim was to evaluate best strategies to improve N fluxes of agro-ecosystems within a perspective of sustainable intensification. Indicators of agronomic efficiency and environmental quality were considered. The results showed that agronomic benefits were observed with a continuous soil cover (conservation agriculture and cover crops), which enhanced nitrogen use efficiency (+17%) and crop yields (+34%), although in some cases these might be overestimated due to modelling limitations. An overall environmental improvement was found with continuous soil cover and long-term change from mineral to organic inputs (NLeach 45 Mg ha 121), which were effective in the sandy soils of western and eastern Veneto with low SOM, improving the soil-water balance and nutrients availability over time. Results suggest that AEM subsidies should be allocated at a site-specific level that includes pedo-climatic variability, following a result-oriented approach

Exponentially hard problems are sometimes polynomial, a large deviation analysis of search algorithms for the random Satisfiability problem, and its application to stop-and-restart resolutions

A large deviation analysis of the solving complexity of random 3-Satisfiability instances slightly below threshold is presented. While finding a solution for such instances demands an exponential effort with high probability, we show that an exponentially small fraction of resolutions require a computation scaling linearly in the size of the instance only. This exponentially small probability of easy resolutions is analytically calculated, and the corresponding exponent shown to be smaller (in absolute value) than the growth exponent of the typical resolution time. Our study therefore gives some theoretical basis to heuristic stop-and-restart solving procedures, and suggests a natural cut-off (the size of the instance) for the restart.Comment: Revtex file, 4 figure

Capturing Relic Neutrinos with beta-decaying nuclei

We summarize a novel approach which has been recently proposed for direct detection of low energy neutrino backgrounds such as the cosmological relic neutrinos, exploiting neutrino/antineutrino capture on nuclei that spontaneously undergo beta decay.Comment: Talk given by G. Mangano at TAUP2007 Conference, Sendai, Japan, September 200