Parallelization of a Six Degree of Freedom Entry Vehicle Trajectory Simulation Using OpenMP and OpenACC

The art and science of writing parallelized software, using methods such as Open Multi-Processing (OpenMP) and Open Accelerators (OpenACC), is dominated by computer scientists. Engineers and non-computer scientists looking to apply these techniques to their project applications face a steep learning curve, especially when looking to adapt their original single threaded software to run multi-threaded on graphics processing units (GPUs). There are significant changes in mindset that must occur; such as how to manage memory, the organization of instructions, and the use of if statements (also known as branching). The purpose of this work is twofold: 1) to demonstrate the applicability of parallelized coding methodologies, OpenMP and OpenACC, to tasks outside of the typical large scale matrix mathematics; and 2) to discuss, from an engineers perspective, the lessons learned from parallelizing software using these computer science techniques. This work applies OpenMP, on both multi-core central processing units (CPUs) and Intel Xeon Phi 7210, and OpenACC on GPUs. These parallelization techniques are used to tackle the simulation of thousands of entry vehicle trajectories through the integration of six degree of freedom (DoF) equations of motion (EoM). The forces and moments acting on the entry vehicle, and used by the EoM, are estimated using multiple models of varying levels of complexity. Several benchmark comparisons are made on the execution of six DoF trajectory simulation: single thread Intel Xeon E5-2670 CPU, multi-thread CPU using OpenMP, multi-thread Xeon Phi 7210 using OpenMP, and multi-thread NVIDIA Tesla K40 GPU using OpenACC. These benchmarks are run on the Pleiades Supercomputer Cluster at the National Aeronautics and Space Administration (NASA) Ames Research Center (ARC), and a Xeon Phi 7210 node at NASA Langley Research Center (LaRC)

Optical study of the hyper-luminous X-ray source 2XMM J011942.7+032421

We present the identification and characterization of the optical counterpart to 2XMM J011942.7+032421, one of the most luminous and distant ultra-luminous X-ray sources (ULXs). The counterpart is located near a star forming region in a spiral arm of the galaxy NGC 470 with u, g, and r magnitudes of 21.53, 21.69, and 21.71 mags, respectively. The luminosity of the counterpart is much larger than that of a single O-type star, indicating that it may be a stellar cluster. Our optical spectroscopic observations confirm the association of the X-ray source and the optical counterpart with its host galaxy NGC 470, which validates the high, > 10^41 erg/s, X-ray luminosity of the source. Its optical spectrum is embedded with numerous emission lines, including H recombination lines, metallic forbidden lines and more notably the high-ionization HeII (lambda 4686 A) line. This line shows a large velocity dispersion of $\simeq$ 410 \kms, consistent with the existence of a compact (< 5 AU) highly-ionized accretion disc rotating around the central X-ray source. The 1.4 x 10^37 erg/s luminosity of the HeII line emission makes the source one of the most luminous ULXs in the emission of that line. This, together with the high X-ray luminosity and the large velocity dispersion of the HeII emission, suggests that the source is an ideal candidate for more extensive follow-up observations for understanding the nature of hyper-luminous X-ray sources, a more luminous subgroup of ULXs and more likely candidates for intermediate-mass black holes.Comment: Accepted for publication in Astrophysical journal Letters, 14 pages, 3 figure

Logistics services and Lean Six Sigma implementation: a case study

Purpose: This paper analyses the application of Lean Six Sigma framework for supporting continuous improvement in logistics services. Both the lean philosophy and the Six Sigma methodology have become two of the most important initiatives for continuous improvement in organizations. The combination of both alternatives - Lean Six Sigma (LSS) - brings significant benefits for companies applying this method and its influence in logistics services can be relevant. Design/methodology/approach: A case study on the logistics services of a large consumer electronics company is performed. In this sector, high quality in logistics services is crucial. Using within-case and cross-case analyses, the paper discusses the implementation of LSS in two internal logistics processes. Findings: The paper identifies important implementation aspects when applying LSS to logistics services, such as continuous improvement structure, strategic analysis, cross-functional teams, and process management. Furthermore, the paper discusses the potential in logistics services of the DMAIC approach and tools like VSM, SIPOC and Process Mapping. Practical implications: The paper analyses two logistics processes where LSS has been applied - a payment process and a request-to-ship process. The analysis of both processes offers relevant information about organizational implementation in a logistics services environment, about process improvement and about the use of LSS tools. Originality/value: Firstly, this paper addresses the gap in literature about LSS and logistics’ activities. Furthermore, the case company, with more than 9.000 employees and distributing its products to more than 100 countries, constitutes a valuable source of information to obtain insights in the implications of implementing LSS in logistics services

A CrC^{r} Closing Lemma for a Class of Symplectic Diffeomorphisms

We prove a $C^r$ closing lemma for a class of partially hyperbolic symplectic diffeomorphisms. We show that for a generic $C^r$ symplectic diffeomorphism, $r =1, 2, ...,$, with two dimensional center and close to a product map, the set of all periodic points is dense

Logistics services and Lean Six Sigma implementation: a case study

Purpose: This paper analyses the application of Lean Six Sigma framework for supporting continuous improvement in logistics services. Both the lean philosophy and the Six Sigma methodology have become two of the most important initiatives for continuous improvement in organizations. The combination of both alternatives - Lean Six Sigma (LSS) - brings significant benefits for companies applying this method and its influence in logistics services can be relevant. Design/methodology/approach: A case study on the logistics services of a large consumer electronics company is performed. In this sector, high quality in logistics services is crucial. Using within-case and cross-case analyses, the paper discusses the implementation of LSS in two internal logistics processes. Findings: The paper identifies important implementation aspects when applying LSS to logistics services, such as continuous improvement structure, strategic analysis, cross-functional teams, and process management. Furthermore, the paper discusses the potential in logistics services of the DMAIC approach and tools like VSM, SIPOC and Process Mapping. Practical implications: The paper analyses two logistics processes where LSS has been applied - a payment process and a request-to-ship process. The analysis of both processes offers relevant information about organizational implementation in a logistics services environment, about process improvement and about the use of LSS tools. Originality/value: Firstly, this paper addresses the gap in literature about LSS and logistics’ activities. Furthermore, the case company, with more than 9.000 employees and distributing its products to more than 100 countries, constitutes a valuable source of information to obtain insights in the implications of implementing LSS in logistics services