251,974 research outputs found

    The check problem of food thermal processes: A mathematical solution

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    To calculate the sterilizing value U, and hence, the microbial lethality F in thermal processes of the canned food, starting from the knowledge of heating time B, a mathematical modeling was carried out. Therefore it\u2019s useful to verify the desired microbial destruction (check problem) and it was obtained by reversing the mathematical approach carried out in a previous work [23] for the design problem, namely to calculate the retort heating time B, starting from a desired lethality F and, hence from the fh/U parameter. A comparison between the predicted fh/U, related to the lethality F calculated with the mathematical model of the present work and the desired Stumbo\u2019s values of fh/U, provided the following statistical indices: a mean relative error MRE=1.18\ub12.11%, a mean absolute error MAE=1.61\ub111.7 and a determination coefficient R2=0.991, better than ANN models. The mathematical procedure, quickly usable also with a spreadsheet, replaces the 57 Stumbo\u2019s tables and 18512 data sets in the Ball formula method

    Mathematical modelling of tissue-engineering angiogenesis

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    We present a mathematical model for the vascularisation of a porous scaffold following implantation in vivo. The model is given as a set of coupled non-linear ordinary differential equations (ODEs) which describe the evolution in time of the amounts of the different tissue constituents inside the scaffold. Bifurcation analyses reveal how the extent of scaffold vascularisation changes as a function of the parameter values. For example, it is shown how the loss of seeded cells arising from slow infiltration of vascular tissue can be overcome using a prevascularisation strategy consisting of seeding the scaffold with vascular cells. Using certain assumptions it is shown how the system can be simplified to one which is partially tractable and for which some analysis is given. Limited comparison is also given of the model solutions with experimental data from the chick chorioallantoic membrane (CAM) assay

    Reason, causation and compatibility with the phenomena

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    'Reason, Causation and Compatibility with the Phenomena' strives to give answers to the philosophical problem of the interplay between realism, explanation and experience. This book is a compilation of essays that recollect significant conceptions of rival terms such as determinism and freedom, reason and appearance, power and knowledge. This title discusses the progress made in epistemology and natural philosophy, especially the steps that led from the ancient theory of atomism to the modern quantum theory, and from mathematization to analytic philosophy. Moreover, it provides possible gateways from modern deadlocks of theory either through approaches to consciousness or through historical critique of intellectual authorities. This work will be of interest to those either researching or studying in colleges and universities, especially in the departments of philosophy, history of science, philosophy of science, philosophy of physics and quantum mechanics, history of ideas and culture. Greek and Latin Literature students and instructors may also find this book to be both a fascinating and valuable point of reference

    Reassessing Neo-Kantianism. Another Look at Hermann Cohen’s Kant Interpretation

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    This article is a novel assessment of Hermann Cohen’s theoretical philosophy, starting out from his Kant interpretation. Hermann Cohen was the head and founder of the Marburg School of Neo- Kantianism. In the beginning, hence, I will commence with some initial reflections on the makeup and importance of this school, before I move on to Cohen’s revolutionary Kant interpretation and its ramification for the Marburg School in general

    Mathematical modeling of the dynamics of a shovel with flexible coupling

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    To study the possible ergonomic and energetic advantages on the use of a shovel with a flexible coupling, a dynamic analysis of the motion of the blade together with the lifted raw material was conducted. By this dynamic analysis, ordinary differential equations were set up. Therefore the closed-form solutions were found to obtain useful equations for simulation. The application of mathematical modeling both to the blade with elastic coupling and to the traditional one, allowed to quantify the zeroing of the operator effort in the second half of the blade lifting. However, in the first part of the lifting an effort increase occurs, but in this first phase the operator can take advantage from the support on the thigh, thus lightening the load on the spine
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