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Stringent quality requirements for safety-critical applications drive the demand for “zero defects” in modern ICs. In this context, delay characterization of standard cells for resistive open defects is an increasing concern due to aggressive timing margins in digital circuits. The problem is made worse by the large number of open defect sites in standard cells, combined with a wide range of defect resistance values for each site. This incurs possible prohibitive costs for defect simulation and characterization. To alleviate this complexity, we propose Resistive Fault Dominance (RFD) for resistive open defects. RFD eliminates simulations of certain open defects with intermediate defect resistance values that are guaranteed to exceed specified timing margins for standard cells, based on tests for specific “dominant” open defects. This can significantly reduce the computational costs of cell library characterization and simulation effort by 84%-91%. An algorithmic fault simulation methodology for resistive open defects on parasitic-extracted (PEX) transistor level netlists is developed. 

According to a new design paradigm called Converging Design, high-level optimization objectives such as resilience and sustainability can be pursued through iterative simulation and feedback. Unlike traditional design processes that prioritize desirable seismic performance at various seismic hazard levels, the Converging Design methodology also considers the long-term ecological impact of construction and functional recovery. This methodology requires navigating competing priorities, which can be pursued through multi-objective optimization (MOO). However, computational costs and incorporating uncertainty in seismic analysis also demand that optimization frameworks use algorithms and analysis resolutions that are appropriate to the decisions being made as the design is refined. While such a framework could be applied to any material, mass timber systems are increasingly attractive as a potential sustainable solution for buildings. In this study, using a Python-based object-oriented program, an automated structural design procedure is developed to evaluate the seismic and sustainability performance of parametrically definable mass timber building configurations. Different geometric classes with Cross-Laminated Timber Rocking Walls are modeled using OpenSees and are automatically designed. Their behavior is then studied to provide insights into the relationship between structural variables and the optimization objectives. The results show a clear trade-off between Seismic Safety (the inverse of risk) and Global Warming Potential due to the construction of different design options, although the nature of this trade-off depends on the desired seismic behavior limit states. The developed software thus enables designers to efficiently explore a range of early design options for mass timber lateral systems and to achieve optimal solutions that balance seismic and sustainability performance. 

Mass timber products are gaining popularity in North America as an alternative to traditional construction materials as part of both the gravity and lateral force-resisting system. However, several knowledge gaps still exist in terms of their expected seismic performance and plausible hybridizations with other materials, e.g. steel energy dissipators. This research explores the potential use of wall spine systems consisting of mass ply panels (MPP) and steel buckling-restrained braces (BRBs) as energy dissipators. The proposed BRB-MPP spine assembly makes up the lateral force-resisting system of a three-story mass-timber building segment that will be tested under cyclic quasi-static loading at Oregon State University. The proposed design methodology follows displacement-based design principles to determine the minimum required stiffness to limit inelastic story drift ratios at the design earthquake level. The MPP spine and BRB-to-MPP connections were capacity designed to resist forces transferred by the BRBs at roof drift ratios beyond the risk-targeted Maximum Considered Earthquake (MCER). This design solution provides an interesting alternative for the design of modern mass timber buildings. The results obtained in the experimental campaign will be used to validate the design methodology and the behavior of the innovative structural system. 

Excited states of the 64Cu (Z=29,N=35) nucleus have been probed using heavy-ion-induced fusion evaporation reaction and an array of Compton-suppressed Clovers as detection system for the emitted γ rays. More than 50 new transitions have been identified and the level scheme of the nucleus has been established up to an excitation energy Ex∼6 MeV and spin ∼10ℏ. The experimental results have been compared with those from large-basis shell-model calculations that facilitated an understanding of the single-particle configurations underlying the level structure of the nucleus. 

Abstract Galaxy clusters are expected to be both dark matter (DM) reservoirs and storage rooms for the cosmic-ray protons (CRp) that accumulate along the cluster's formation history. Accordingly, they are excellent targets to search for signals of DM annihilation and decay atγ-ray energies and are predicted to be sources of large-scaleγ-ray emission due to hadronic interactions in the intracluster medium (ICM).In this paper, we estimate the sensitivity of the Cherenkov Telescope Array (CTA) to detect diffuseγ-ray emission from the Perseus galaxy cluster.We first perform a detailed spatial and spectral modelling of the expected signal for both the DM and the CRp components. For each case, we compute the expected CTA sensitivity accounting for the CTA instrument response functions. The CTA observing strategy of the Perseus cluster is also discussed.In the absence of a diffuse signal (non-detection), CTA should constrain the CRp to thermal energy ratioX₅₀₀within the characteristic radiusR₅₀₀down to aboutX₅₀₀< 3 × 10^-3, for a spatial CRp distribution that follows the thermal gas and a CRp spectral index α_CRp= 2.3. Under the optimistic assumption of a pure hadronic origin of the Perseus radio mini-halo and depending on the assumed magnetic field profile, CTA should measure α_CRpdown to about Δα_CRp≃ 0.1 and the CRp spatial distribution with 10% precision, respectively. Regarding DM, CTA should improve the current ground-basedγ-ray DM limits from clusters observations on the velocity-averaged annihilation cross-section by a factor of up to ∼ 5, depending on the modelling of DM halo substructure. In the case of decay of DM particles, CTA will explore a new region of the parameter space, reaching models withτ_χ> 10²⁷s for DM masses above 1 TeV.These constraints will provide unprecedented sensitivity to the physics of both CRp acceleration and transport at cluster scale and to TeV DM particle models, especially in the decay scenario.