Fault tolerant software modules for SIFT

The implementation of software fault tolerance is investigated for critical modules of the Software Implemented Fault Tolerance (SIFT) operating system to support the computational and reliability requirements of advanced fly by wire transport aircraft. Fault tolerant designs generated for the error reported and global executive are examined. A description of the alternate routines, implementation requirements, and software validation are included

Isomorphic chain complexes of Hamiltonian dynamics on tori

In this work we construct for a given smooth, generic Hamiltonian $H : \mathbb{S}^1\times\mathbb{T}^n \longrightarrow \mathbb{R}$ on the torus a chain isomorphism $\Phi_* : \big(C_*(H),\partial^M_*\big) \longrightarrow \big(C_*(H),\partial^F_*\big)$ between the Morse complex of the Hamiltonian action $A_H$ on the free loop space of the torus $\Lambda_0(\mathbb{T}^n)$ and the Floer complex. Though both complexes are generated by the critical points of $A_H$, their boundary operators differ. Therefore the construction of $\Phi$ is based on counting the moduli spaces of hybrid type solutions which involves stating a new non-Lagrangian boundary value problem for Cauchy-Riemann type operators not yet studied in Floer theory

Towards general purpose LES model of injection and atomization

Conferencia plenaria por invitaciónInjection and atomization of liquid is widely used in many industrial and domestic applications such as, fuel injection in engines or burners, spray painting, medical sprays, spray drying, etc. Various approaches are used to simulate two-phase flows. Usually, interface tracking methods are used to simulate the primary atomization while a dispersed method such as the Lagrangian particle-tracking approach may be used to model the final spray. Despite progresses in numerical methods and computer performance, complete simulation of atomization and spray remains inaccessible for many applications. A possibility consists to extend the ELSA approach to the well-established LES framework combined with an interface density equation for subgrid scales. A postulated transport equation of the interface density is used to describe the subgrid spray formation ranging from interface wrinkling, ligaments, and sheets up to the droplets. The objective of our work is to extend the LES ELSA method developed by Chesnel et al. into a general purpose solver OpenFOAM . The method has been adapted for unstructured mesh to address applications. The interface capturing method is based on the transport of a liquid volume fraction, αl. To sustain the sharp gradient of αl an additional compressive term is added to the equation. LES formulation induced a subgrid term SGSαl that is not compatible with numerical procedure used to capture the interface. The advantage of the compressive method is the possibility to switch it off when SGSαl become important, i.e. when the interface fluctuations become important at subgrid scale. In order to improve ELSA method a coupling with Lagrangian particle will be initialized. Lagrangian particle are create when liquid structure become droplet. The diameter and the number of particle are determined via the liquid volume fraction and via the interface density. The Eulerian equations have to be linked to the Lagrangian phase, this is achieved through the liquid turbulent diffusion flux closure. The aim of my work is to study the LES atomization method and make comparison of the liquid dispersion around the axes with a reference DNS.Universidad de Málaga. Campus de Excelencia Internacional Andalucia Tech. Conferencias del plan propio de la UM

Post-Quantum Cryptography: S381 Cyclic Subgroup of High Order

Currently there is an active Post-Quantum Cryptography (PQC) solutions search, which attempts to find cryptographic protocols resistant to attacks by means of for instance Shor polynomial time algorithm for numerical field problems like integer factorization (IFP) or the discrete logarithm (DLP). The use of non-commutative or non-associative structures are, among others, valid choices for these kinds of protocols. In our case, we focus on a permutation subgroup of high order and belonging to the symmetric group S381. Using adequate one-way functions (OWF), we derived a Diffie-Hellman key exchange and an ElGamal ciphering procedure that only relies on combinatorial operations. Both OWF pose hard search problems which are assumed as not belonging to BQP time-complexity class. Obvious advantages of present protocols are their conceptual simplicity, fast throughput implementations, high cryptanalytic security and no need for arithmetic operations and therefore extended precision libraries. Such features make them suitable for low performance and low power consumption platforms like smart cards, USB-keys and cellphones.Comment: 9 pages, 13 figure

Measurement, estimation, and prediction of software reliability

Quantitative indices of software reliability are defined, and application of three important indices is indicated: (1) reliability measurement, (2) reliability estimation, and (3) reliability prediction. State of the art techniques for each of these procedures are presented together with considerations of data acquisition. Failure classifications and other documentation for comprehensive software reliability evaluation are described

Sheltify

Modular, collapsible, community building, and mental health enhancing refugee shelter. Nexus Maximus IV The Challenge: Innovation for Refugees and Displaced Populations One of the great challenges of our time is how to help refugees and displaced populations, and how to prevent the causes in the first place. Every minute, 24 people around the world are forced to flee their homes. That’s 34,000 people a day who leave everything behind in the hope of finding safety and a better tomorrow. The impact of war, political, racial and religious conflict, and environmental crises of famine and climate change, have caused great suffering and there is a great opportunity to do better. The issues these populations and the countries who receive them face are diverse and complex. They include public health, housing/built environment, cultural integration, public safety, employment/economic and more. How can innovation address these challenges? How do we create the social systems and products to support a healthy, safe and integrated program for refugees? How do we address the physical, emotional, and social needs of refugees to restore hope and opportunity? The solutions may be as far ranging as the challenges, exploring the acute needs during a crisis, as well as the chronic needs of the permanently displaced; looking at immigration and adjustments to new cultures. We encourage participants to draw upon all disciplines, from health professions to architecture, engineering to design, ethics, communication and every way of thinking we have, to find better ways to innovate on physical solutions, processes, policies, systems, and more. Recap from poster presentationshttps://jdc.jefferson.edu/nexusmaximus/1004/thumbnail.jp

Applying a phase field approach for shape optimization of a stationary Navier-Stokes flow

We apply a phase field approach for a general shape optimization problem of a stationary Navier-Stokes flow. To be precise we add a multiple of the Ginzburg--Landau energy as a regularization to the objective functional and relax the non-permeability of the medium outside the fluid region. The resulting diffuse interface problem can be shown to be well-posed and optimality conditions are derived. We state suitable assumptions on the problem in order to derive a sharp interface limit for the minimizers and the optimality conditions. Additionally, we can derive a necessary optimality system for the sharp interface problem by geometric variations without stating additional regularity assumptions on the minimizing set