In shingled writing, cross-talk noise from an adjacent track occurs when a rather wide track read-head is used, which causes inter-track-interference (ITI). A compensation method has been proposed. However, the linearity of the superposed response from the tracks should be examined for such signal processing. Experimental studies on the superposition of readback waveforms and nonlinearity caused by overwriting of adjacent tracks were carried out. The superposition of the readback waveform was almost precisely maintained. The off-track overwrite performance showed a large track edge over-write noise. Overwrite noise caused by a nonlinear transition shift was also observed.

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  We propose analysis of multiple spin states in radical carbon zigzag edge graphene-like molecules. Calculations based on density function theory (DFT) revealed that the highest spin state was most stable in every radical carbon edge asymmetric molecule. A typical C₆₄H₁₇ molecule has five unpaired electrons, which creates three possible molecular spin states of Sz=1/2, 3/2, and 5/2. The Sz=5/2 state was the most stable among these states. Such DFT results coincided with a simple magnetic counting rule to give a localized spin of Sz=+2/2 to one radical carbon site, whereas it gave Sz=-1/2 at the nearest carbon and +1/2 at the second nearest. A total molecular spin of Sz was obtained by using the simple sum of those numbers. Radical carbon zigzag edge nano-graphene is a promising candidate for designing new materials with strong magnetism. In addition, we studied oxygen-substituted zigzag edges occupied by four electrons. These four spins canceled each other out in two tetrahedral orbits, which led to weak molecular magnetism.

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  We have developed an open-type magnetically shielded room composed of magnetic square cylinders that has been used for an actual MRI in a hospital. To improve shielding performance, we propose here a method to control the path of the magnetic flux in the wall composed of the magnetic square cylinders by changing the magnetic permeability in each direction of the square cylinders spatially. First, we discuss a method to control the magnetic permeability in each direction of the square cylinders independently by inserting slits without changing the outside dimensions of the square cylinders, by using 3-D magnetic field analysis. Then, the effectiveness of the design of controlling the flux pass was shown by magnetic field analysis and experiments.

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