Modern Approaches to Exact Diagonalization and Selected Configuration Interaction with the Adaptive Sampling CI Method.

Recent advances in selected configuration interaction methods have made them competitive with the most accurate techniques available and, hence, creating an increasingly powerful tool for solving quantum Hamiltonians. In this work, we build on recent advances from the adaptive sampling configuration interaction (ASCI) algorithm. We show that a useful paradigm for generating efficient selected CI/exact diagonalization algorithms is driven by fast sorting algorithms, much in the same way iterative diagonalization is based on the paradigm of matrix vector multiplication. We present several new algorithms for all parts of performing a selected CI, which includes new ASCI search, dynamic bit masking, fast orbital rotations, fast diagonal matrix elements, and residue arrays. The ASCI search algorithm can be used in several different modes, which includes an integral driven search and a coefficient driven search. The algorithms presented here are fast and scalable, and we find that because they are built on fast sorting algorithms they are more efficient than all other approaches we considered. After introducing these techniques, we present ASCI results applied to a large range of systems and basis sets to demonstrate the types of simulations that can be practically treated at the full-CI level with modern methods and hardware, presenting double- and triple-ζ benchmark data for the G1 data set. The largest of these calculations is Si2H6 which is a simulation of 34 electrons in 152 orbitals. We also present some preliminary results for fast deterministic perturbation theory simulations that use hash functions to maintain high efficiency for treating large basis sets

Sea Surface Salinity Variability from Simulations and Observations: Preparing for Aquarius

Oceanic fresh water transport has been shown to play an important role in the global hydrological cycle. Sea surface salinity (SSS) is representative of the surface fresh water fluxes and the upcoming Aquarius mission scheduled to be launched in December 2010 will provide excellent spatial and temporal SSS coverage to better estimate the net exchange. In most ocean general circulation models, SSS is relaxed to climatology to prevent model drift. While SST remains a well observed variable, relaxing to SST reduces the range of SSS variability in the simulations (Fig.1). The main objective of the present study is to simulate surface tracers using a primitive equation ocean model for multiple forcing data sets to identify and establish a baseline SSS variability. The simulated variability scales are compared to those from near-surface argo salinity measurements

2009 Goose Bay Experiment Ocean Measurements

During late February and early March 2009, a field experiment was performed using the NASA P3 over the Labrador Sea. During this experiment, expendable probes deployed from the aircraft acquired ocean mixed layer temperature, salinity and currents Probes were deployed during three flights of the four. Overall 7 AXBTs, 15 AXCTDs and 7 AXCPs were deployed with a success rate of nearly 70%. This is much lower than expected based on prior experience deploying from other aircraft. But given the difficulties associated with the Pneumatic Sonobuoy Launch Tube mechanism on the NASA P3, this rate likely can be improved significantly by using a different deployment mechanism. Additionally, two sets of collocated measurements of AXBTs, AXCPs and AXCTDs were made to verify the drop rates and measurements of the old AXBTs. While there were differences in the measurements, the old AXCTDs are performing well. The expendable data from the experiment are compared to the Argo profiles in the region to check for consistency. Comparisons indicate all the expendable probes acquired useful data and are well within the range of values measured by Argo floats

The Influence of Antenna Pattern on Faraday Rotation in Remote Sensing at L-band

Faraday rotation is a change in the polarization vector of electromagnetic radiation that occurs as the waves propagate from the Earth surface through the ionosphere to a spaceborne sensor. This change can cause errors in monitoring parameters at the surface such as soil moisture and sea surface salinity and it is an important consideration for radiometers on future missions in space such as NASA's Aquarius mission and ESA's SMOS mission. Two prominent strategies for compensating for Faraday rotation are using a sum of the signal at two polarizations and using the correlation between the signals at the two polarizations. These strategies work for an idealized antenna. This paper evaluates the strategies in the context of realistic antennas such as will be built for the Aquarius radiometer. Realistic antennas will make small differences that need to be included in planning for retrieval algorithms in future missions

The Dust in the Atmosphere of Mars and Its Impact on the Human Exploration of Mars: A NESC Workshop

The NASA Engineering and Safety Center (NESC) Chief Scientist provided support to produce an NESC final report on the "Dust in the Atmosphere of Mars and Its Impact on Human Exploration" workshop held June 1315, 2017, in Houston, TX. This report follows the standard NESC report format to describe the findings, observations, and NESC recommendations developed by the workshop participants. The key stakeholders for the final report are the Mars mission designers and engineers for the precursor missions and the crewed mission, and the NESC. Further stakeholders are the mission planners deciding on the payload selections for the Mars missions

Neural networks of human nature and nurture

Neural network methods have facilitated the unification of several unfortunate splits in psychology, including nature versus nurture. We review the contributions of this methodology and then discuss tentative network theories of caring behavior, of uncaring behavior, and of how the frontal lobes are involved in the choices between them. The implications of our theory are optimistic about the prospects of society to encourage the human potential for caring. Los métodos de redes neuronales han facilitado la unificación de varias desafortunadas divisiones en psicología, incluida la de naturaleza versus crianza. Se revisan aquí las contribuciones de esta metodología, para luego examinar las propuestas teóricas basadas en redes acerca de la conducta de cuidado, la conducta de descuido y cómo los lóbulos frontales están involucrados en las elecciones entre éstas. Las implicaciones de nuestra teoría son optimistas acerca de los prospectos de la sociedad para fortalecer el potencial humano para el cuidado.

Information-rich Task Allocation and Motion Planning for Heterogeneous Sensor Platforms

This paper introduces a novel stratified planning algorithm for teams of heterogeneous mobile sensors that maximizes information collection while minimizing resource costs. The main contribution of this work is the scalable unification of effective algorithms for de- centralized informative motion planning and decentralized high-level task allocation. We present the Information-rich Rapidly-exploring Random Tree (IRRT) algorithm, which is amenable to very general and realistic mobile sensor constraint characterizations, as well as review the Consensus-Based Bundle Algorithm (CBBA), offering several enhancements to the existing algorithms to embed information collection at each phase of the planning process. The proposed framework is validated with simulation results for networks of mobile sensors performing multi-target localization missions.United States. Air Force. Office of Scientific Research (Grant FA9550-08-1-0086)United States. Air Force. Office of Scientific Research. Multidisciplinary University Research Initiative (FA9550-08-1-0356

What Levels of Coupled Cluster Theory Are Appropriate for Transition Metal Systems? A Study Using Near-Exact Quantum Chemical Values for 3d Transition Metal Binary Compounds.

Transition metal compounds are traditionally considered to be challenging for standard quantum chemistry approximations like coupled cluster (CC) theory, which are usually employed to validate lower level methods like density functional theory (DFT). To explore this issue, we present a database of bond dissociation energies (BDEs) for 74 spin states of 69 diatomic species containing a 3d transition metal atom and a main group element, in the moderately sized def2-SVP basis. The presented BDEs appear to have an (estimated) 3σ error less than 1 kJ/mol relative to the exact solutions to the nonrelativistic Born-Oppenheimer Hamiltonian. These benchmark values were used to assess the performance of a wide range of standard single reference CC models, as the results should be beneficial for understanding the limitations of these models for transition metal systems. We find that interactions between metals and monovalent ligands like hydride and fluoride are well described by CCSDT. Similarly, CCSDTQ appears to be adequate for bonds between metals and nominally divalent ligands like oxide and sulfide. However, interactions with polyvalent ligands like nitride and carbide are more challenging, with even CCSDTQ(P)Λ yielding errors on the scale of a few kJ/mol. We also find that many perturbative and iterative approximations to higher order terms either yield disappointing results or actually worsen the performance relative to the baseline low level CC method, indicating that complexity does not always guarantee accuracy