20 research outputs found

    Hierarchical analysis and multi-scale modelling of rat cortical and trabecular bone

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    The aim of this study was to explore the hierarchical arrangement of structural properties in cortical and trabecular bone and to determine a mathematical model that accurately predicts the tissue's mechanical properties as a function of these indices. By using a variety of analytical techniques, we were able to characterize the structural and compositional properties of cortical and trabecular bones, as well as to determine the suitable mathematical model to predict the tissue's mechanical properties using a continuum micromechanics approach. Our hierarchical analysis demonstrated that the differences between cortical and trabecular bone reside mainly at the micro- and ultrastructural levels. By gaining a better appreciation of the similarities and differences between the two bone types, we would be able to provide a better assessment and understanding of their individual roles, as well as their contribution to bone health overall

    Designing and establishment of ISO/IEC 17025 in laboratories of national inland water aquaculture center and south Iran aquaculture research center

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    The project was carried out between June of 2011 and November of 2012,8 laboratories of research center in Anzali (Plankton, Algae, Hydrochemistry, Physiology, Ichthyology, Bentose, Parazitology, Virology) and 7 laboratories of research center in Ahvaz (Clinical pathology, Plankton, Hydrochemistry, Physiology, Ichthyology, Bentose, Parazitology, Virology) were selected for accreditation. The main stages for establishment of the system consisted of: 1-Conducting a gap analysis to compare the present state of the laboratories with ISO/IEC 17025 2-Training General requirements for the competence of testing and calibration laboratories Validation of methods Estimation of uncertainty Internal audits 3- Performing of technical and management requirements 4-Submit of quality manual to ASCB center in England in order to accredit In August of 2012 The main results were including: 1-Increase the accuracy of measurement in laboratories 2-Improvement of the Repeatability and Reproducibility of the test methods 3-Traceability and standardization of test methods 4- Calibration of measurement instruments 6- Updating of test methods 7-Standardization of physical condition of the laboratories 8- Getting the certification from ASCB center i

    DNA structure spectroscopy by synthetic pigments using LED lighting

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    It is clear that DNA concentration and biological detection devices have many applications in the fields of genetics and biotechnology. For this goal, some similar devices have been designed working with the laser light which the disadvantages of them are high prices and the use of significant amounts of sample volume. But this designed device which works with LED light has very cheap manufacturing cost. The amounts of DNA used in this device are very low, about a few micro-liters and measurement of small, fast and portable it is also the advantages of these devices. The Data recorded as voltage versus time and the Fourier transform the frequency domain. From the frequency curve, by using the Byrlambrt it is possible to obtain the relative concentrations of DNA, viruses and assays measuring DNA damage and many other applications. By use of this device, the concentration of DNA colored with three different pigments was measured

    Multi-objective attuned design of damping controllers using frequency-based functions in smart grids

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    Increasing expansion of power systems is accompanied by innovations in smart grid solutions to maintain system stability. This paper formulates the dual-dimensional supplementary damping controller (SDC) and accelerating power system stabilizer (PSS2B) design as a multi-objective optimization procedure including both performance and robustness criteria. In wide-area operation, PSS2B is used for damping low-frequency swings and maintaining the robustness of controller in a wide range of swing frequencies. A dual-dimensional controller model is employed for the SDC. The robustness requirement is procured by using the idea of pseudospectra to handle the changes of power system parameters and the time delay introduced by wide-area damping controller (WADC). The multi-objective optimization problem is solved using an improved non-dominated sorting genetic algorithm-II (INSGA-II) based on fuzzy decision making (FDM) method. Different simulations are carried out on a 4-machine 2-area test system in order to validate the effectiveness and robustness of the designed controllers
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