Cross-validation of predictive models for deoxynivalenol in wheat at harvest

2013 ◽  
Vol 6 (4) ◽  
pp. 389-397 ◽  
Author(s):  
M. Camardo Leggieri ◽  
H.J. Van der Fels-Klerx ◽  
P. Battilani
Keyword(s):  
The Netherlands ◽  
Empirical Model ◽  
Predictive Models ◽  
Random Sampling ◽  
Field Data ◽  
Cross Validation ◽  
Historical Data ◽  
Mechanistic Model ◽  
Dutch Model ◽  
Modelling Approaches

To date, several models that predict deoxynivalenol (DON) in wheat at harvest are available. This study aimed to evaluate the performance of two of such models, including a mechanistic model developed in Italy and an empirical model developed in the Netherlands. To this end, field data collected in the periods 2002-2004 and 2009-2011 in Italy, and in the period 2001-2010 in the Netherlands were used. These historical data covered farm observations at 1,306 wheat fields, of which 155 in the Netherlands and 1,151 in Italy. A subset of 10% of the Italian data, derived by random sampling from the total Italian dataset, was used to validate both the Italian and the Dutch model. Additionally, the Italian mechanistic model was validated using the total Dutch dataset. Before validating the Dutch model, it was recalibrated using the remaining 90% of the Italian data. Results showed that predictions of both modelling approaches (mechanistic and empirical) for independent wheat fields were in accordance. Applying a threshold for DON concentration of 1,250 ?g/kg, the mechanistic DON model predicted 90% of the samples correctly. Results for cross-validation of the mechanistic DON model and the recalibrated empirical DON model showed that 93% of the samples were correctly predicted. In general, no more than 6% of underestimates were observed.

scholarly journals Assessing elderly’s functional balance and mobility via analyzing data from waist-mounted tri-axial wearable accelerometers in timed up and go tests

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lisha Yu ◽  
Yang Zhao ◽  
Hailiang Wang ◽  
Tien-Lung Sun ◽  
Terrence E. Murphy ◽  
...  
Keyword(s):  
Predictive Models ◽  
Cross Validation ◽  
Motor Coordination ◽  
Predictive Accuracy ◽  
Short Form ◽  
Community Dwelling ◽  
Regularized Regression ◽  
Balance Assessment ◽  
Timed Up And Go ◽  
Functional Balance

Abstract Background Poor balance has been cited as one of the key causal factors of falls. Timely detection of balance impairment can help identify the elderly prone to falls and also trigger early interventions to prevent them. The goal of this study was to develop a surrogate approach for assessing elderly’s functional balance based on Short Form Berg Balance Scale (SFBBS) score. Methods Data were collected from a waist-mounted tri-axial accelerometer while participants performed a timed up and go test. Clinically relevant variables were extracted from the segmented accelerometer signals for fitting SFBBS predictive models. Regularized regression together with random-shuffle-split cross-validation was used to facilitate the development of the predictive models for automatic balance estimation. Results Eighty-five community-dwelling older adults (72.12 ± 6.99 year) participated in our study. Our results demonstrated that combined clinical and sensor-based variables, together with regularized regression and cross-validation, achieved moderate-high predictive accuracy of SFBBS scores (mean MAE = 2.01 and mean RMSE = 2.55). Step length, gender, gait speed and linear acceleration variables describe the motor coordination were identified as significantly contributed variables of balance estimation. The predictive model also showed moderate-high discriminations in classifying the risk levels in the performance of three balance assessment motions in terms of AUC values of 0.72, 0.79 and 0.76 respectively. Conclusions The study presented a feasible option for quantitatively accurate, objectively measured, and unobtrusively collected functional balance assessment at the point-of-care or home environment. It also provided clinicians and elderly with stable and sensitive biomarkers for long-term monitoring of functional balance.

scholarly journals Performance Evaluation of Soft Computing for Modeling the Strength Properties of Waste Substitute Green Concrete

2021 ◽  
Vol 13 (5) ◽  
pp. 2867
Author(s):  
Muhammad Izhar Shah ◽  
Muhammad Nasir Amin ◽  
Kaffayatullah Khan ◽  
Muhammad Sohaib Khan Niazi ◽  
Fahid Aslam ◽  
...  
Keyword(s):  
Predictive Models ◽  
Parametric Study ◽  
Cross Validation ◽  
Strength Properties ◽  
Fine Aggregate ◽  
Agricultural Industry ◽  
Green Concrete ◽  
Concrete Properties ◽  
Water To Cement Ratio ◽  
Sugarcane Bagasse Ash

The waste disposal crisis and development of various types of concrete simulated by the construction industry has encouraged further research to safely utilize the wastes and develop accurate predictive models for estimation of concrete properties. In the present study, sugarcane bagasse ash (SCBA), a by-product from the agricultural industry, was processed and used in the production of green concrete. An advanced variant of machine learning, i.e., multi expression programming (MEP), was then used to develop predictive models for modeling the mechanical properties of SCBA substitute concrete. The most significant parameters, i.e., water-to-cement ratio, SCBA replacement percentage, amount of cement, and quantity of coarse and fine aggregate, were used as modeling inputs. The MEP models were developed and trained by the data acquired from the literature; furthermore, the modeling outcome was validated through laboratory obtained results. The accuracy of the models was then assessed by statistical criteria. The results revealed a good approximation capacity of the trained MEP models with correlation coefficient above 0.9 and root means squared error (RMSE) value below 3.5 MPa. The results of cross-validation confirmed a generalized outcome and the resolved modeling overfitting. The parametric study has reflected the effect of inputs in the modeling process. Hence, the MEP-based modeling followed by validation with laboratory results, cross-validation, and parametric study could be an effective approach for accurate modeling of the concrete properties.

scholarly journals Deepening and Connecting Democratic Processes. The Opportunities and Pitfalls of Mini-Publics in Renewing Democracy

2018 ◽  
Vol 7 (11) ◽  
pp. 236
Author(s):  
Ank Michels ◽  
Harmen Binnema
Keyword(s):  
The Netherlands ◽  
Random Sampling ◽  
Policy Making ◽  
Specific Design ◽  
Fundamental Nature ◽  
The Core ◽  
Equal Chance ◽  
Political Impact ◽  
Selection Of

In recent decades, so-called “mini-publics” have been organized in many countries to renew policy making and democracy. One characteristic of mini-publics is that the selection of the participants is based on random sampling or sortition. This gives each member of the community an equal chance of being selected. Another feature is that deliberation forms the core of the process of how proposals are developed. In this paper, we investigate the possibilities and challenges of sortition and deliberation in the context of the call for a deepening of democracy and more citizen engagement in policy making. Based on extensive research on citizens’ forums (G1000) in The Netherlands, we show the potential of mini-publics, but a number of shortcomings as well. Some of these are related to the specific design of the G1000, while others are of a more fundamental nature and are due to the contradictory democratic values that deliberative mini-publics try to combine. One of these concerns the tension between the quality of deliberation and political impact. We conclude that combining institutional approaches could be a way out to deal with these tensions and a step forward to both deepen and connect democratic processes.

On the Early Cambrian age of two late orogenic granites from. west-central Ahaggar (Algerian Sahara)

1969 ◽  
Vol 6 (1) ◽  
pp. 25-37 ◽  
Author(s):  
J. Boissonnas ◽  
S. Borsi ◽  
G. Ferrara ◽  
J. Fabre ◽  
J. Fabries ◽  
...  
Keyword(s):  
Random Sampling ◽  
Field Data ◽  
Large Scale ◽  
Early Cambrian ◽  
Basement Complex ◽  
West Central ◽  
Algerian Sahara ◽  
Igneous Activity ◽  
Made In

The Pharusian belt of west-central Ahaggar belongs to the 'basement complex' underlying the Paleozoic and later sediments of the Sahara. This paper reports and discusses the Rb–Sr ages obtained on total rocks and minerals from two granitic stocks of the belt: the Tioueiine and Iskel intrusions.Both plutons gave good whole-rock isochrons, which show that the systems were closed 560 ± 40 m.y. ago with respect to Rb and Sr. This is, most probably, the age of crystallization. Three of the four values obtained on biotites are somewhat lower and scattered in the range 502–526 m.y. The discrepancies are probably due to deuteric reactions or incipient weathering. They can be ascribed neither to the loss of 87Sr during the cooling down of the granites, nor to rejuvenation by some later thermal or tectonic event.These studies confirm previous results of random sampling in Ahaggar and prove that large-scale igneous activity took place during the Early Cambrian Epoch. Knowing from field data that the Tioueiine and Iskel are late orogenic granites, it must be concluded that the Pharusian orogeny came to an end at that time.Such a result contradicts early assumptions, made in the field, of a middle Precambrian age for the Pharusian orogeny. It gives further weight to modern ideas concerning the 700–500 m.y. events in Africa, and it leaves time for erosion to create the Saharian platform before the deposition of the first Paleozoic sandstones.

The Republic Was an Empire

2020 ◽  
pp. 139-155
Author(s):  
Jonathan Scott
Keyword(s):  
The Netherlands ◽  
The State ◽  
Political Union ◽  
The Past ◽  
Imperial Ideology ◽  
Military Revolution ◽  
The Republic ◽  
The Moment ◽  
Dutch Model

This chapter deals with the circumstances leading to the first of three Anglo-Dutch wars. Beginning with a proposal for political union, the chapter addresses the growing animosity between the English and the Dutch through two major themes. In the first place, from the moment of its foundation the English republic was, and behaved like, an empire. Second, it was the product, as in the Netherlands, of a rebellion and fiscal/military revolution which built the state. More than its Dutch model, the English republic entailed a sharp, indeed spectacular, break with the past, accompanied by a revolutionary as well as an imperial ideology.

WEATHER AND THE ECOLOGY OF APANTELES FUMIFERANAE VIER. (HYMENOPTERA: BRACONIDAE)

1988 ◽  
Vol 120 (S146) ◽  
pp. 57-70 ◽  
Author(s):  
Vincent G. Nealis
Keyword(s):  
Field Data ◽  
Historical Data ◽  
Spruce Budworm ◽  
Temperature Dependent ◽  
Maturation Period ◽  
Phenological Model ◽  
Model Based ◽  
Egg Maturation ◽  
Adult Parasitoid ◽  
Specific Mortality

AbstractThe effects of weather on the spruce budworm parasitoid, Apanteles fumiferanae Vier., are examined. A phenological model based on temperature-dependent rates of development and longevity is developed and validated with field data. The model is then used to explore the effects of age-specific mortality on phenological behaviour of the parasitoid and the seasonal synchrony between the parasitoid and its host over several years. The results show that the parasitoid adult ecloses well before the host reaches an age susceptible to parasitism but that the egg maturation period and the longevity of the parasitoid diminish the consequences of the apparent asynchrony. The historical data reveal that the relative phenological characteristics of A. fumiferanae and its host vary little from year to year. In the second part of the study, temperature is shown to have a strong effect on adult parasitoid activity and on the rate of oviposition.

Sign in / Sign up

Export Citation Format

Share Document