Search results for " forest"

Effects of weekend starvation and the duration of daily feeding on production parameters of rainbow trout Oncorhynchus mykiss

2021

Abstract It would often be practical to starve the cultivated fishes over the weekends, e.g. to save in labour costs. We evaluated the possibility that domesticated juvenile rainbow trout (Oncorhynchus mykiss) could compensate for the lost growth of the 2-day weekend starvation by either hyperphagic response and/or by lower feed conversion ratio, compared to the fish fed every day in an 8-week experiment. Rainbow trout (initial weight c. 30 g, temperature 16 °C) starved during the weekends were able to increase feed intake during the weekdays clearly above the intake of the control fish after the first two weekends, also seen as an increase of the compensation coefficients over the last fou…

Breaking the curse of dimensionality in quadratic discriminant analysis models with a novel variant of a Bayes classifier enhances automated taxa ide…

2013

Macroinvertebrate samples are commonly used in biomonitoring to study changes on aquatic ecosystems. Traditionally, specimens are identified manually to taxa by human experts being time-consuming and cost intensive. Using the image data of 35 taxa and 64 features, we propose a novel variant of the quadratic discriminant analysis for breaking the curse of dimensionality in quadratic discriminant analysis models. Our variant, called a random Bayes array (RBA), uses bagging and random feature selection similar to random forest. We explore several variations of RBA. We consider three classification (i.e taxa identification) decisions: majority vote, averaged posterior probabilities, and a novel…

Model-Assisted Estimation Through Random Forests in Finite Population Sampling

2021

In surveys, the interest lies in estimating finite population parameters such as population totals and means. In most surveys, some auxiliary information is available at the estimation stage. This information may be incorporated in the estimation procedures to increase their precision. In this article, we use random forests (RFs) to estimate the functional relationship between the survey variable and the auxiliary variables. In recent years, RFs have become attractive as National Statistical Offices have now access to a variety of data sources, potentially exhibiting a large number of observations on a large number of variables. We establish the theoretical properties of model-assisted proc…

Le specie alloctone invasive in Sicilia: caratterizzazione del fenomeno, strategie di colonizzazione e possibili strategie di contrasto

2014

Methomyl analogues with increased biological activity towards F7T maize mitochondria

1987

Abstract Methomyl analogues were synthesized by substituting alkyl moieties (C 2 -C 21 ) in the place of the carbamic methyl. They were assayed on mitochondria isolated from male sterile (F 7 T) and male fertile (F 7 N) maize. They had no action on F 7 N mitochondria. The heptadecyl (C 17 ) and heneicosanyl (C 21 ) derivatives had no conspicuous effect on F 7 T mitochondria. By contrast, the ethyl, propyl, butyl, nonyl, tridecyl (C 13 ) and pentadecyl (C 15 ) derivatives had the same type of activity as Methomyl on F 7 T mitochondria, namely stimulation of NADH oxidation and inhibition of malate oxidation. Moreover, the concentration at which they were maximally effective decreased from 10 …

Adaptive sparse representation of continuous input for tsetlin machines based on stochastic searching on the line

2021

This paper introduces a novel approach to representing continuous inputs in Tsetlin Machines (TMs). Instead of using one Tsetlin Automaton (TA) for every unique threshold found when Booleanizing continuous input, we employ two Stochastic Searching on the Line (SSL) automata to learn discriminative lower and upper bounds. The two resulting Boolean features are adapted to the rest of the clause by equipping each clause with its own team of SSLs, which update the bounds during the learning process. Two standard TAs finally decide whether to include the resulting features as part of the clause. In this way, only four automata altogether represent one continuous feature (instead of potentially h…

A Theoretical Learning Model Combining Stochastic Cellular Automata and Economic Indicators to Simulate Land Use Change

2015

The study of change in land use has been included in territorial planning to inform spatial planners and policy makers of the possible developments they face in order to optimize future management decisions. In this paper the authors present the core of an original learning model coupling stochastic Cellular Automata and economic indicators to simulate the land use change. This model is an important step in building an “environmental virtual laboratory” to explore, explain and forecast land use change.

Il contributo di Jeannette Villepreux Power alla conoscenza e agli zoologici del paesaggio della Sicilia dell’800.

2012

Soil REE patterns as tracers of the emplacement of metal-rich anthropogenic materials. A case study in Moa (Cuba)

2019

Purpose: Are rare earth element (REE) patterns employable as tracers in human interventions of bulk soil disturbances, when high concentrations of metals are involved in the in situ soil disturbance? In terms of bulk soil disturbance, it is difficult to distinguish between bulk soil disturbances and emplacement of new earthen material. Chemical fingerprinting, in particular REE plus yttrium, is applied across many fields, but predominantlyin tracking the sources of potential environmental contaminants. Materials and methods: The REE normalised patterns (HNO 3 :HF:HCl 3:1:1 digestion, ICP-MS) of two Calcaric Cambisols were compared with those of a Geric Ferralsol (Novic, Technic) originated …

Preface: Proceedings of the 14th IASWS international conference

2018

Preface to the Proceedings of the 14th IASWS international conference