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In this paper, a novel multi-kernel support vector machine (MKSVM) combining global and local characteristics of the input data is proposed. Along with, a parameter tuning approach is developed using the fruit fly optimization (FFO), which is applied to stock market movement direction prediction problem. At first, factor analysis is used for identifying reduced key features called as factor scores from the raw stock index data which when applied to the model contributes to improvement in prediction performance. Subsequently, a hybrid kernel method combining local and global characteristics of input data is proposed, where polynomial is used for global kernel and radial basis function is utilized for local kernel. Additionally, FFO-based parameter tuning scheme is proposed to enhance the prediction performance further. Lastly, the evolving MKSVM with best feature subset and optimal parameters is used to predict stock market movement direction based upon historical data series. For evaluation and illustration purposes, three significant stock databases, NYSE, DJI and S&P 500 are used as testing targets. The effectiveness of this proposed approach is proved by three different stock market datasets, which demonstrate that the proposed approach outperforms the MKSVM with default parameter, MKSVM with PSO, MKSVM with GA and other methods. In addition, our findings reveal that the optimization strategy proposed here may be used as a promising choice forecasting tool for better generalization ability higher forecasting accuracy. [ABSTRACT FROM AUTHOR]

Glaciers have an important hydrological buffering effect, but their current rapid reduction raises concerns about future water availability and management. This work presents a hydrological sensitivity analysis to different climatic and glacier cover conditions, carried out over four catchments with area between 8 and 1050 km2, and with glacierization between 2% and 70%, in the Italian Alps. The analysis is based on past observations, and exploits a unique dataset of glacier change and hydro-meteorological data. The working approach is aimed at avoiding uncertainties typical of future runoff projections in glacierized catchments. The results highlight a transition from glacial to nival hydrological regime, with the highest impacts in August runoff over smaller catchments. The buffering effect of current glaciers has largely decreased if compared to the Little Ice Age, up to 75% for larger catchments, but it is still important during warm and dry summers like 2003. We confirm a non-linear relationship between glacier contribution in late summer and catchment area/percent glacierization. The peak in runoff attributable to glacier melt, expected in the next 2–3 decades on highly glacierized alpine catchments, has already passed in the study area.

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The study aimed to obtain a monthly average temperature equation estimated from the analysis of the variability of temperatures (maximum, average and minimum), to Jaboticabal /SP. The analysis of the parameters was made monthly, seasonal, annual and interannual. Data (1971-2013) were collected in a Agrometeorological Station of the Universidade Estadual Paulista (UNESP) at Jaboticabal Campus(Lat; 21°14'05"S; Long: 48°17'09"O;. Alt: 616.01m). On the data were applied statistical methods (mean, standard deviation and coefficient of variation). Were also correlated the monthly averages obtained by the standard method (INMET) and by the method of extreme temperatures. The results showed that standard deviation of the temperatures had a slow variations with low coefficient of variation. The equations obtained between the mean values of standard INMET and the mean of the extreme, can be used for micro region of Jaboticabal with good accuracy in results. [ABSTRACT FROM AUTHOR]

Seawater warming is impacting marine ecosystems, but proper evaluation of change requires the availability of long-term biological data series. Mesco Reef (Ligurian Sea, Italy) offers one of the longest Mediterranean data series on sessile epibenthic communities, based on underwater photographic surveys. Photographs taken in four stations between 20 m and 40 m depth allowed calculating the percent cover of conspicuous species in 1961, 1990, 1996, 2008, and 2017. Multivariate analysis evidenced an abrupt compositional change between 1990 and 1996. A parallel change was observed in Ligurian Sea temperatures. Two invasive macroalgae (Caulerpa cylindracea and Womersleyella setacea) became dominant after 1996. Community diversity was low in 1961 to 1996, rapidly increased between 1996 and 2008, and exhibited distinctly higher values in 2008–2017. A novel community emerged from the climate shift of the 1990s, with many once characteristic species lost, reduced complexity, biotic homogenization, greater diversity and domination by aliens. Only continued monitoring will help envisage the possibility for a reversal of the present phase shift or for further transformations driven by global change. [ABSTRACT FROM AUTHOR]

Glaciers have an important hydrological buffering effect, but their current rapid reduction raises concerns about future water availability and management. This work presents a hydrological sensitivity analysis to different climatic and glacier cover conditions, carried out over four catchments with area between 8 and 1050 km2, and with glacierization between 2% and 70%, in the Italian Alps. The analysis is based on past observations, and exploits a unique dataset of glacier change and hydro-meteorological data. The working approach is aimed at avoiding uncertainties typical of future runoff projections in glacierized catchments. The results highlight a transition from glacial to nival hydrological regime, with the highest impacts in August runoff over smaller catchments. The buffering effect of current glaciers has largely decreased if compared to the Little Ice Age, up to 75% for larger catchments, but it is still important during warm and dry summers like 2003. We confirm a non-linear relationship between glacier contribution in late summer and catchment area/percent glacierization. The peak in runoff attributable to glacier melt, expected in the next 2–3 decades on highly glacierized alpine catchments, has already passed in the study area. [ABSTRACT FROM AUTHOR]