Prevladavanje sukoba između znanja i odgoja za vrijednosti. Bioetika - primjer integracijskog modela odgoja i obrazovanja

This paper is based on a number of premises of fundamental nature. The first premise contains the idea of the historical conflict with the universal-social obligation to educate ali members of society without regard to their racial origin, sex, religion and social status. Because of its universal-social dimension, modern society enforces this obligation by appropriate legislation which includes sanctions against its transgressors. The most important sanction regards coercive abrogation of parental and guardian authority over a child with the purpose to satisfy the demand of his/her legislative obligation to be educated. The origin of this historical conflict is not the pure demand of education, but the gradual taking over of some very important educational activities from parents or guardians by the public, i.e. educational institutions. The second premise contains the idea of the historically formed and supported attitude that the status of knowledge is neutral. This premise additionally supports the previous one. In other words, if the propose of educational institutions is the mediation of knowledge and cognitions from various epistemic sources, and if, at the same time, it is (and was) believed that this knowledge and these cognitions are neutral or that perhaps they are not due to their specific epistemic source (such as some subjects from the field of the humanities and social sciences), then in the process of their mediation they should be presented as such, i.e. neutral. The third premise contains the idea according to which education - here primarily conceived as a self-understood component of both the activity and purpose of educational institutions - neither is nor can ever be conceived as neutral, since education is not neutral either in se or per se. Accordingly, both education and educational activity always imply that the educators’ activity is engaged in value, since otherwise one could not talk about education, but perhaps about ideological training, psychological pressure, brainwashing, physical violence and tyranny, etc. The fourth premise contains some aspects of the ideas expressed in the previous premises. In other words, if one starts from the presupposition that all knowledge and cognitions mediated through various subjects of the educational system are necessarily neutral, and if, at the same time, one believes that the educational activities of educational institutions are self-understood, then what follows is the unclarity of the value-based Vision, according to which educational activities are to be modeled and implemented in educational institutions. Modern school is simply inconceivable without certain subjects, such as mathematics, computer science, physics, chemistry, geology, geography, biology, genetics, anatomy, and various other branches of the natural sciences. The prevalence of the above subjects in the modern educational system does not facilitate educational activities, since, as has already been said, education is always a value-engaged activity, whereas the knowledge and cognitions of the above mentioned branches of the natural Sciences tend towards a conditional status of neutrality at the least - a conditional status because value neutrality is sustainable only to some degree, i.e. only on the level of listing empirical facts conceived as mere heaps of information and data, whereas any such neutrality ceases on the level of the theoretical and practical interpretation of these facts, since bare facts and their interpretation are not the same thing. Considering that the schoolbook contents of these subjects are already – logically or not – contaminated with theoretical and practical interpretations, the question whether the knowledge and cognitions of the various branches of the natural Sciences can ever be mediated in a value-free fashion is well-grounded. The answer to the question about the (non)existence of an aprioristically set value engagement of educational institutions in educational activities depends upon the answer to the above question. The fifth premise contains the idea of the need to critically evaluate the presupposed neutrality of the knowledge and cognitions mediated in educational institutions in relation to the value engagement of the educational activities of the same institutions. In other words, what conditions and possibilities do exist for a real and mutual support of education in today’s system of education? This paper searches for an answer to this question in the field of bioethics, understanding bioethics as an example of an integration model of education. This model is being defined here for the first time, and is not an already aprioristically defined model. If in one’s mind one goes a step further from what is expressed in the above premises, then this integration model is what seems to impose itself as the only possible solution to the issue of the educational process discussed above. This paper sets out some relevant arguments which additionally support the above premises and which, if shown as possible, provide adequate justification to the integration model of education on the example of bioethics

Accurate 2D Reconstruction for PET Scanners based on the Analytical White Image Model

In this paper, we provide a precise mathematical model of crystal-to-crystal response which is used to generate the white image - a necessary compensation model needed to overcome the physical limitations of the PET scanner. We present a closed-form solution, as well as several accurate approximations, due to the complexity of the exact mathematical expressions. We prove, experimentally and analytically, that the difference between the best approximations and real crystal-to-crystal response is insignificant. The obtained responses are used to generate the white image compensation model. It can be written as a single closed-form expression making it easy to implement in known reconstruction methods. The maximum likelihood expectation maximization (MLEM) algorithm is modified and our white image model is integrated into it. The modified MLEM algorithm is not based on the system matrix, rather it is based on ray-driven projections and back-projections. The compensation model provides all necessary information about the system. Finally, we check our approach on synthetic and real data. For the real-world acquisition, we use the Raytest ClearPET camera for small animals and the NEMA NU 4-2008 phantom. The proposed approach overperforms competitive, non-compensated reconstruction methods.Comment: 37 pages, 16 figure

Accurate PET Reconstruction from Reduced Set of Measurements based on GMM

In this paper, we provide a novel method for the estimation of unknown parameters of the Gaussian Mixture Model (GMM) in Positron Emission Tomography (PET). A vast majority of PET imaging methods are based on reconstruction model that is defined by values on some pixel/voxel grid. Instead, we propose a continuous parametric GMM model. Usually, Expectation-Maximization (EM) iterations are used to obtain the GMM model parameters from some set of point-wise measurements. The challenge of PET reconstruction is that the measurement is represented by the so called lines of response (LoR), instead of points. The goal is to estimate the unknown parameters of the Gaussian mixture directly from a relatively small set of LoR-s. Estimation of unknown parameters relies on two facts: the marginal distribution theorem of the multivariate normal distribution; and the properties of the marginal distribution of LoR-s. We propose an iterative algorithm that resembles the maximum-likelihood method to determine the unknown parameters. Results show that the estimated parameters follow the correct ones with a great accuracy. The result is promising, since the high-quality parametric reconstruction model can be obtained from lower dose measurements, and is directly suitable for further processing.Comment: 23 pages, 10 figures, submitted to "Signal Processing" by Elsevie