Dan A. Iordache

A novel approach to the analysis of human growth

ObjectivesSeveral formulations have been proposed in order to model human growth from birth to maturity. They are usually based on “ad hoc” heuristic assumptions. In the present contribution we adopt, as an alternative, a completely general (interdisciplinary) approach, based on the formalism of the Phenomenological Universalities (PUN).MethodsThe main PUN class investigated to date, i.e. UN, can only account for the overall growth pattern. For a realistic description it is necessary to add to it one or more “spurts”, as expected on biological grounds, due to the stimulation of growth and sex hormones.ResultsA new PUN class (UN + FM) is generated and shown to be able to provide excellent agreement with standard auxological datasets. The accuracy of the fitting and reliability of the model suggest applications both at the diagnostic and therapeutic level.ConclusionsThe developed formalism can be suitably related to the biological description of bone plate growth under selective hormonal stimulation on the bone epiphysis; i.e., the additional increase of stature is the “macroscopic” response to a well defined biological signal.

Charge Coupled Devices as Particle Detectors

As it is well known, while the most important advantages of the charge coupled devices, as high energy particle detectors are related to their (a) extremely high sensitivity (very important for the underground laboratories, also) and (b) huge number of very small independent components (pixels) of the magnitude order of , which allow the separate impressions of many different “signatures” of (silicon lattice defects produced by) these particles, their main disadvantages refer to the (a) difficulty to distinguish between the capture traps (of free electrons and holes, resp.) produced by the radiation particles and the numerous types of traps due to the contamination or dopants and (b) huge number of types of lattice defects due to the irradiation. For these reasons, this work achieves a state of art of the (i) main experimental methods and (ii) physical parameters intended to the characterization of the main types of traps embedded in the silicon lattice of CCDs. There were identified also some new physical parameters useful in this aim, as the polarization degree of capture cross-sections and the state character, as well as some new useful notions, as the trans-Fermi level capture states.

Analysis of compatibility with experimental data of fractal descriptions of the fracture parameters

In order to check if the Fractal theory could be a useful tool for some quantitative descriptions of the fracture parameters, the present work studied different theoretical models (e.g. the Bazant’s Size Effect Law (SEL) [1], the Modified Size Effect Law [2,3] and the Carpinteri’s MultiFractal Scaling Law (MFSL) [4] of the fracture parameters of concrete specimen, and the compatibility of some of the above studied theoretical models relative to the experimental data, using certain recent procedures to study the global and local compatibility. The fracture parameters can be considered as main quantities for computational procedures for modeling the fracture of a certain ensemble (a suddenly emerging phenomena). In the next phase, the thermoelastic generation of ultrasonic perturbations in semitransparent solids was analyzed (using computer simulation) so as to find similarities with material properties as fractal dimensions, when the heat source is a laser radiation. The algorithm, the numerical analysis has taken into account three main physical phenomena: the absorption of electromagnetic energy in substance with heat generation; thermal diffusion with electromagnetic energy based heat source and elastodynamic wave generation by thermoelastic expansion.

Advance Multispectral Analysis for Segmentation of Satellite Image

This paper presents an application with record performance for electromagnetic spectrum analysis of multispectral satellite image. The analysis method is an application-specific pixels oriented to images segmentation. This kind of segmentation is used in remote sensing for land cover and land use classification and change detection. Regions of the image are clustered separately and then the results are combined, for this the processing method employs two types of clustering algorithms, each specialized to its task and steered towards obtaining a final meaningful segmentation. The results show good spatial coherency in segments and coherent borders between regions that were segmented separately.

Study of Some Complex Systems by Using Numerical Methods

The study deals with the complex systems in Nature by using of some specific numerical methods. First the method of the physical similarity is used for the characterization of the fluids flow regimes. Then, the method of the power laws and some of its multiple uses in Physics and another related fields are analyzed. The method of phenomenological universality, applied to the description of the growth processes is also discussed. The authors results presented in the paper were mainly obtained by computer simulations using the finite difference (FD) method and the classical gradient method (CGM).

Physics Teaching In The Technical Universities And The Physics Evolution in the Last Century

Starting from the study of the Physics evolution (as described by the main results obtained in frame of the Physics Nobel prizes), this work aimed to study and point out some possibilities of improvement of the didactic technologies intended to better Physics training and understanding by future engineers.