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Analysing Bell Experiments through Test Factors: Applications to Randomness and Strength of Nonlocality
Get PDFThis work presents practical tools to analyse Bell experiments---experiments demonstrating correlations that defy classical explanations and proving that nature violates local realism. We begin by showing that in the Bell scenario specified by n parties with each party having a choice of m binary-outcome measurements---the (n,m,2) scenario---projecting weakly-signalling settings-conditional outcome distributions onto the smallest-dimensional affine subspace (containing the no-signalling set) via an L^2-distance-minimising map preserves correlators. This result ensures that Bell inequalities written in terms of correlators remain invariant under such projections, and we provide an efficient construction method for the projection operator that avoids computationally costly steps such as Gauss-Jordan elimination and matrix inversion. This will be a useful tool to obtain a readily computable point estimate of a no-signalling distribution when presented with experimental data weakly violating the no-signalling conditions.
An important application of a Bell experiment is generation of randomness that can be certified without making assumptions about the inner workings of the measurement devices. We examine the probability estimation framework, a method for certifying randomness in Bell experiments by estimating outcome probabilities conditioned on measurement settings in the presence of adversarial side information, offering a self-contained proof of its asymptotic optimality and clarifying the structure of optimal adversarial strategies. These results are applied concretely in the (2,2,2) Bell scenario, where we analytically characterise no-signalling-constrained attacks and demonstrate the robustness of probability estimation factors against deviations from expected experimental statistics. We further study possible extensions of the framework to quantum-limited adversaries in the (2,2,2) scenario and no-signalling-constrained adversaries in the more general (n,m,k) scenarios.
Finally, we analyse two recent experiments demonstrating local operations and shared randomness-based genuine multipartite nonlocality in a three-party network. Traditional standard-deviation-based approaches to demonstrating the presence of nonlocality in Bell experimental data overlook memory effects. Instead, by introducing a computationally efficient polytope approximation technique for optimising test factors while maintaining statistical validity, we construct an adaptation of the prediction-based ratio protocol and use it to quantify the strength of nonlocality by obtaining valid p-values
Assessment of Lake Salvador Shoreline Dynamics to Support Restoration of Submerged Aquatic Vegetation in Jean Lafitte National Historical Park and Preserve, Louisiana
Get PDFHigh wave energy degrades shoreline habitat between Lake Salvador and Jean Lafitte National Historical Park and Preserve (JELA), Louisiana. JELA constructed a northern breakwater in 2004, and a southern breakwater in 2024 to protect the shoreline and promote restoration of submerged aquatic vegetation (SAV). This study analyzes Sentinel-2 imagery to quantify coastal loss along the JELA-Lake Salvador using the Change Polygon Approach, assessing annual, cumulative and major storm event-associated shoreline changes for January 2017-2025. SAV cover, nekton diversity, wave energy, and turbidity were measured before-and-after southern breakwater construction to monitor ecological and environmental outcomes. The JELA-Lake Salvador shoreline has lost ~0.31 km2 since 2017, with the southern extent deteriorating 2.64x more than the long-term protected northern extent. Major storm events are associated with ~70% of total net loss. The southern SAV habitat remains suitable for natural recruitment. This study informs JELA managers of recent shoreline dynamics, supporting adaptive management to promote and sustain SAV and protect the vulnerable wetland shoreline
Hydraulic Optimization of RTC Systems: Number, Placement, and PID Control Rules of FCDs in Distributed Flood Routing
Get PDFClimate change, characterized by an increase in the frequency and intensity of extreme weather events, combined with rapid urbanization, has significantly strained urban drainage networks by exacerbating surface runoff and increasing flood risk. Traditional strategies, such as upsizing conduits or constructing additional detention facilities, often require substantial financial investment and space, which are not always feasible. This study presents an alternative, cost-effective solution by optimizing Real-Time Control (RTC) systems applied to a real case study (i.e., the New Orleans drainage network model) to enhance the drainage performance without major infrastructure expansion.
RTC is a promising strategy for dynamic flood mitigation; however, its effectiveness depends heavily on the optimal placement, number, and control rules of Flow Control Devices (FCDs). To address this, a fully integrated Python-based optimization framework was developed, coupling Multi Objective Genetic Algorithms (MOGA) or Multi Objective Particle Swarm Optimization (MOPSO) with the SWMM hydraulic model. The framework simultaneously determines the optimal locations, quantities, and Proportional-Integral-Derivative (PID) control parameters for FCDs under two different optimization methods. The methodology was applied to a real-world case study in New Orleans, Louisiana, USA.
Performance was evaluated under a range of design storms (1-, 2-, 5-, 10-, 25-, and 50-year return periods). Results demonstrated that the optimized RTC configuration could reduce peak discharge, delay peak flow timing, and significantly reduce flooding, achieving up to 80% improvement in network efficiency under certain conditions. Shifting towards dynamic modeling represents a significant advancement in the field of urban stormwater management, offering more reliable and robust solutions for mitigating flooding in complex urban environments. This study aims to address the gaps in previous research by conducting the entire optimization process (i.e., find the optimal quantity, placement, and PID controllers) within a Python environment, including the reading, writing, manipulating, and optimizing the SWMM file
Oral History Interview with Robert Horton (Part 2)
Get PDFRobert Horton, a native of New Orleans, shared his life journey, highlighting his experiences from the 1980s to the present. He discussed his early education, his father\u27s incarceration, and the impact of Hurricane Katrina on his family. Horton\u27s involvement in grassroots organizing began with Black Men United and the People\u27s Institute for Survival and Beyond, focusing on economic justice, fatherhood, and community policing. He later worked with Critical Resistance and Step Up Louisiana, developing new leaders and advocating for the Workers Bill of Rights. Horton emphasized the importance of political education and civic engagement in community organizing. Robert Horton discusses the interconnectedness of racial capitalism and capitalism, emphasizing that capitalism inherently benefits white individuals due to racial biases. He identifies as a revolutionary, advocating for social change and anti-racism. Horton highlights the exploitation of the Latinx community, who perform jobs previously held by African Americans, and the potential for tension between the two groups. Horton stresses the importance of challenging white supremacy systemically to achieve true racial justice.https://scholarworks.uno.edu/ejrloh/1001/thumbnail.jp