Noninvasive neuromodulation techniques such as Transcranial Magnetic Stimulation are enabled by electromagnetic induction with applications in neuroscience research and the treatment of neurological disorders. Current systems are effective but research continues on improving key performance metrics such as precise targeting, focality, and depth of penetration. Additional functions are also being studied; tunable excitation field patterning, reconfigurable depth of penetration, multiple excitation sites, power efficient waveforms and reduced extraneous excitation. Multichannel, multi-coil arrays show promise in achieving many of these parameters in one multifunctional array as opposed to the single-function commercial coils (circular, figure-8 or H coil) being used today.As such, our central focus is to determine whether multifunction dense arrays, despite their many challenges, are a tractable technical approach for future neuromodulation systems. Therefore, the results in this paper are twofold. First, we report the design, fabrication and demonstration of a scalable multichannel (12 channels) or multifunction dense array system to assess the potential to perform these functions in one system. Second, we demonstrate that the depth of penetration of the magnetic field can be reconfigured by varying current magnitude and phase of the smaller coil diameters in the array to achieve the same decay profile performance of a larger diameter coil. Only simulations exist in the literature to date, to the best of our knowledge, we report the first measurements of hexagonal shaped coils in multi-coil arrays have increased depth of penetration over circular shaped coil-based arrays.

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Metal Building Systems (MBS) make up a substantial portion of nonresidential, low-rise construction in the U.S. Given their wide spread use, it is desirable to understand their performance during a seismic event. Previous pseudostatic, cyclic testing indicates an absence of ductility in these systems. This lack of ductility arises from the inherent design concepts behind using web-tapered frames with no flange or web compactness limits, causing buckling limit states to govern the strength of the frames. In light of the lack of ductility, it is obvious that the current practice of designing MBS moment frames as Ordinary Moment Frame (OMF) systems, with R=3.5, is inappropriate. Also, simple analytical studies suggest that MBS supporting large masses, such as concrete or masonry exterior cladding or interior mezzanines, may be particularly vulnerable to the lack of ductility. For these reasons, it is desirable to develop a safe, economic, and reliable design procedure for MBS. Earthquake simulation testing of MBS has been performed to provide test data to start this development.Three full-scale MBS specimens have been tested on the NEES/UCSD Large High Performance Outdoor Shake Table. Specimen 1 consisted of a single story MBS frame with metal side wall panels to represent the majority of MBS buildings. Specimen 2 was similar to the first, except with heavy concrete sidewall panels. Specimen 3 consisted of a MBS frame built with compact flanges, a mezzanine attached to one sidewall, and a concrete wall attached to the other. Results from each battery of tests will be presented in this paper. 693

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Multichannel coil array systems offer precise spatiotemporal electronic steering and patterning of electric and magnetic fields without the physical movement of coils or magnets. This capability could potentially benefit a wide range of biomagnetic applications such as low‐intensity noninvasive neuromodulation or magnetic drug delivery. In this regard, the objective of this work is to develop a unique synthesis method, that enabled by a multichannel dense array system, generates complex current pattern distributions not previously reported in the literature. Simulations and experimental results verify that highly curved or irregular (e.g., zig–zag) patterns at singular and multiple sites can be efficiently formed using this method. The synthesis method is composed of three primary components; a pixel cell (basic unit of pattern formation), a template array (“virtual array”: code that disseminates the coil current weights to the “physical” dense array), and a hexagonal coordinate system. Low‐intensity or low‐field magnetic stimulation is identified as a potential application that could benefit from this work in the future and as such is used as an example to frame the research.