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To advance understanding of the multihazard performance of midrise coldformed steel (CFS) construction, a unique multidisciplinary experimental program was conducted on the Large HighPerformance Outdoor Shake Table (LHPOST) at the University of California, San Diego (UCSD). The centerpiece of this project involved earthquake and live fire testing of a fullscale 6story CFS wall braced building. Initially, the building was subjected to seven earthquake tests of increasing motion intensity, sequentially targeting service, design, and maximum credible earthquake (MCE) demands. Subsequently, live fire tests were conducted on the earthquakedamaged building at two select floors. Finally, for the first time, the test building was subjected to two postfire earthquake tests, including a lowamplitude aftershock and an extreme nearfault target MCEscaled motion. In addition, lowamplitude white noise and ambient vibration data were collected during construction and seismic testing phases to support identification of the dynamic state of the building system. This paper offers an overview of this unique multihazard test program and presents the systemlevel structural responses and physical damage features of the test building throughout the earthquakefireearthquake test phases, whereas the componentlevel seismic behavior of the shear walls and seismic design implications of CFSframed building systems are discussed in a companion paper.more » « less

Separations: We introduce a monotone variant of XorSat and show it has exponential monotone circuit complexity. Since XorSat is in NC^2, this improves qualitatively on the monotone vs. nonmonotone separation of Tardos (1988). We also show that monotone span programs over R can be exponentially more powerful than over finite fields. These results can be interpreted as separating subclasses of TFNP in communication complexity. Characterizations: We show that the communication (resp. query) analogue of PPA (subclass of TFNP) captures span programs over F_2 (resp. Nullstellensatz degree over F_2). Previously, it was known that communication FP captures formulas (Karchmer  Wigderson, 1988) and that communication PLS captures circuits (Razborov, 1995). Characterizations: We show that the communication (resp. query) analogue of PPA (subclass of TFNP) captures span programs over F_2 (resp. Nullstellensatz degree over F_2). Previously, it was known that communication FP captures formulas (KarchmerWigderson, 1988) and that communication PLS captures circuits (Razborov, 1995).more » « less

We introduce a new technique for reducing the dimension of the ambient space of lowdegree polynomials in the Gaussian space while preserving their relative correlation structure. As an application, we obtain an explicit upper bound on the dimension of an epsilonoptimal noisestable Gaussian partition. In fact, we address the more general problem of upper bounding the number of samples needed to epsilonapproximate any joint distribution that can be noninteractively simulated from a correlated Gaussian source. Our results significantly improve (from Ackermannlike to "merely" exponential) the upper bounds recently proved on the above problems by De, Mossel & Neeman [CCC 2017, SODA 2018 resp.] and imply decidability of the larger alphabet case of the gap noninteractive simulation problem posed by Ghazi, Kamath & Sudan [FOCS 2016]. Our technique of dimension reduction for lowdegree polynomials is simple and can be seen as a generalization of the JohnsonLindenstrauss lemma and could be of independent interest.more » « less

Unlike compressive sensing where the measurement outputs are assumed to be realvalued and have infinite precision, in onebit compressive sensing, measurements are quantized to one bit, their signs. In this work, our contributions are as follows: 1. We show how to recover the support of sparse highdimensional vectors in the 1bit compressive sensing framework with an asymptotically nearoptimal number of measurements. We do this by showing an equivalence between the task of support recovery using 1bit compressive sensing and a wellstudied combinatorial object known as Union Free Families. 2. We also improve the bounds on the number of measurements for approximately recovering vectors from 1bit compressive sensing measurements. All our results are about universal measurements, namely the measurement schemes that work simultaneously for all sparse vectors. Our improved bounds naturally lead the way to suggest several interesting open problems.more » « less

We prove that the P^NPtype query complexity (alternatively, decision list width) of any boolean function f is quadratically related to the P^NPtype communication complexity of a lifted version of f. As an application, we show that a certain "product" lower bound method of Impagliazzo and Williams (CCC 2010) fails to capture P^NP communication complexity up to polynomial factors, which answers a question of Papakonstantinou, Scheder, and Song (CCC 2014).more » « less