Malamos N.,Western Institute of Technology |
Koutsoyiannis D.,National Technical University of Athens
Hydrological Sciences Journal | Year: 2016
The non-parametric mathematical framework of bilinear surface smoothing (BSS) methodology provides flexible means for spatial (two dimensional) interpolation of variables. As presented in a companion paper, interpolation is accomplished by means of fitting consecutive bilinear surface into a regression model with known break points and adjustable smoothing terms defined by means of angles formed by those bilinear surface. Additionally, the second version of the methodology (BSSE) incorporates, in an objective manner, the influence of an explanatory variable available at a considerably denser dataset. In the present study, both versions are explored and illustrated using both synthesized and real world (hydrological) data, and practical aspects of their application are discussed. Also, comparison and validation against the results of commonly used spatial interpolation methods (inverse distance weighted, spline, ordinary kriging and ordinary cokriging) are performed in the context of the real world application. In every case, the method’s efficiency to perform interpolation between data points that are interrelated in a complicated manner was confirmed. Especially during the validation procedure presented in the real world case study, BSSE yielded very good results, outperforming those of the other interpolation methods. Given the simplicity of the approach, the proposed mathematical framework’s overall performance is quite satisfactory, indicating its applicability for diverse tasks of scientific and engineering hydrology and beyond. EDITOR Z. W. Kundzewicz ASSOCIATE EDITOR A. Carsteanu © 2016 IAHS
Malpas P.J.,University of Auckland |
Corbett A.,Western Institute of Technology
New Zealand Medical Journal | Year: 2012
Medical and nursing student numbers are expected to increase significantly in NZ over the next few years. The ethical, and professional and clinical skills' training of trainee health practitioners is a central and crucial component in medical and nursing education and is underpinned by a strong commitment to improve patient health and well being. In this discussion we reflect on the virtue of empathy and the importance of role modelling in the education of nurses and doctors. We endorse the claim that as medical educators, how and what we teach matters. © NZMA.
Monovasilis T.,Technological Educational Institute of West Macedonia |
Kalogiratou Z.,Western Institute of Technology |
Simos T.E.,King Saud University |
Simos T.E.,University of Peloponnese
International Journal of Modern Physics C | Year: 2011
New symplectic Partitioned Runge-Kutta (SPRK) methods with phase-lag of order infinity are derived in this paper. Specifically two new symplectic methods are constructed with second and third algebraic order. The methods are tested on the numerical integration of Hamiltonian problems and on the estimation of the eigenvalues of the Schrödinger equation. © 2011 World Scientific Publishing Company.
Christaki E.,Aristotle University of Thessaloniki |
Florou-Paneri P.,Aristotle University of Thessaloniki |
Bonos E.,Western Institute of Technology
International Journal of Food Sciences and Nutrition | Year: 2011
Microalgae are known for centuries, but their commercial large-scale production started a few decades ago. They can be grown in open-culture systems such as lakes or highly controlled close-culture systems, have higher productivity than the traditional crops and can be grown in climatic conditions and regions where other crops cannot be grown, such as desert and coastal areas. The edible microalgae are the green algae (chlorophyta) and the cyanobacteria. Microalgae contain substances of high biological value, such as polyunsaturated fatty acids, proteins, amino acids, pigments, antioxidants, vitamins and minerals. They are promising sources for novel products and applications and they can be used in the diet of humans and animals as natural foods with health benefits. Moreover, they can find use in the protection of the environment, as well as in pharmaceuticals, biofuel production and cosmetics. © 2011 Informa UK, Ltd.
Kapageridis I.K.,Western Institute of Technology
Computers and Geosciences | Year: 2015
Experimental variography inthree dimensions based on drillhole data and current modelling software requires the selection of particular directions (azimuth and plunge) and a basic lag distance. Variogram points are then calculated on distances which are multiples of that basic lag. As samples rarely follow a regular grid, directional and distance tolerances are applied in order to have sufficient pairs to calculate reliable variogram points. This process is adequate when drillholes follow a drilling pattern (even if not an exactly regular grid) but can be time consuming and hard when the drilling pattern is irregular or when drillhole orientations vary considerably. Having all variogram points being calculated on multiples of a fixed lag, and the same tolerance being applied throughout the range of distances used, can be very restrictive and a reason for considerable time wasting or even failure to calculate an interpretable experimental variogram. The method discussed in this paper is using k-means clustering of sample pairs based on pair separation distance leading to a number of clusters each representing a different variogram point. This way, lag parameters are adjusted automatically to match the spatial distribution of sample locations and the resulting variogram is improved. Case studies are provided showing the benefits of this method over current fixed-lag experimental variogram calculation techniques. © 2015 Elsevier Ltd.