The work deals with the design of a USB floppy drive driver. It describes the theory needed to design your own floppy drive driver and the output of individual components. The following is a schematic of the floppy drive driver design. The functions for controlling the floppy drive are described, as well as the pitfalls of the ATSAMD21J18A-AU processor used.

This thesis deals with the design of the 3,5" floppy drive emulator with ATMEGA microprocessor unit. The emulator has been designed according to the principles of designing electronic devices, there is also object-control application and firmware for a microcontroller, which supports MFM coding. The thesis also lists all the formats of data stored or transmitted along with some flowcharts.

Fibrin is a biopolymer that assembles into a network during blood coagulation to become the structural scaffold of a blood clot. The precise mechanics of this network are crucial for a blood clot to properly stem the flow of blood at the site of vascular injury while still remaining pliable enough to avoid dislocation. A hallmark of fibrin's mechanical response is strain-stiffening: at small strains, its response is low and linear; while at high strains, its stiffness increases non-linearly with increasing strain. The physical origins of strain-stiffening have been studied for other biopolymer systems but have remained elusive for biopolymer networks composed of stiff filaments, such as fibrin. To understand the origins of this intriguing behavior, we directly observe and quantify the motion of all of the fibers in the fibrin networks as they undergo shear in 3D using confocal microscopy. We show that the strain-stiffening response of a clot is a result of the full network deformation rather than an intrinsic strain-stiffening response of the individual fibers. We observe a distinct transition from a linear, low-strain regime, where all fibers avoid any internal stretching, to a non-linear, high-strain regime, where an increasing number of fibers become stretched. This transition is characterized by a high degree of non-affine motion. Moreover, we are able to precisely calculate the non-linear stress-strain response of the network by using the strains on each fiber measured directly with confocal microscopy and by assuming the fibers behave like linearly elastic beams. This result confirms that it is the network deformation that causes the strain-stiffening behavior of fibrin clots. These data are consistent with predictions for low-connectivity networks with soft, bending, or floppy modes. Moreover, we show that the addition of small contractile cells, platelets, increases the low-strain stiffness of the network while the high-strain stiffness is independent of the presence of the platelets; this is also consistent with expectations for small contractile elements in a network with low connectivity. Our results elucidate the origins of strain-stiffening in fibrin networks as well as the mechanism underlying platelet-induced clot stiffening. / Physics

[pt] Neste trabalho descreve-se o projeto e desenvolvimento de um controlador inteligente de unidades de disco flexível para microcomputadores. O controlador inteligente é baseado no microprocessador 8085 e no controlador de disco 8271 da INTEL. Sua finalidade é livrar o computador hospedeiro das tarefas referentes ao controle de unidades de disco flexível, introduzindo capacidade de processamento paralelo no sistema. Este projeto faz parte do projeto MULTIPUC de estudos de redes de microcomputadores, em execução no Laboratório de Engenharia e Sistema de Computação (LESC) da PUC/RJ. / [en] This work describes the Project and realisation of a floppy-disk intelligent controller. The intelligent controller is besed on the INTEL 8085 microprocessor and on the INTEL 8271 disk controller. Its main purpose is to free the host computer of all the floppy-disk controlling tasks, which results in a additional parallel processing capacity of the system. This work is part of a microcomputer network project called MULTIPUC, which is being built at the Laboratório de Engenharia e Sistemas de Computação (LESC).

The adiabatic or Born-Oppenheimer approximation is often used in molecular calculations to simplify the solution to the Schrodinger equation. The basis of the approximation is the large difference in the relative motions of the nuclei and electrons in the molecule-the electrons are able to respond almost instantly to the movements of the nuclei. Thus, the nuclei may be regarded as being fixed in a certain position and the Schrodinger equation can then be solved using the potential obtained by solving the electronic problem at fixed nuclear configuration. A similar argument can be used to decouple the angular and radial motions of many van der Waals complexes because, like nuclei in molecules, the radial motions in many van der Waals complexes are strongly localized. Fixing the radial separation between the atoms and molecules in the complex to a particular value results in a Schrodinger equation that is much simpler to solve because it is only dependent on angles. van der Waals complexes containing helium atoms, however, present a dilemma because the extremely weak interactions present also lead to large amplitude radial as well as angular motions. Because the basis of the adiabatic approximation is a large difference in time scale between the angular and radial motions, the validity of the adiabatic approximation for helium complexes is uncertain. In this thesis, the adiabatic separation of angular and radial motion is shown to be accurate for extremely floppy complexes of helium by demonstrating its use on the van der Waals molecule He-HCN. A major application of this method is expected to be the quick calculation of approximate wave functions for Diffusion Monte Carlo studies of the rotation of impurity molecules inside ultra-cold droplets of helium. The method presented here is significantly faster than other methods (e.g., Variational Monte Carlo) that have been used to calculate approximate wave functions for Diffusion Monte Carlo.