2,461 research outputs found
Does Consciousness Collapse the Wave Function
A conceptual replication of the Hall-experiment to test the 'subjective
reduction' interpretation of the measurement problem in Quantum Physics is
reported. Two improvements are introduced. First the delay between
pre-observation and final observation of the same quantum event is increased
from a few microseconds in the original experiment to 1 second in this
replication. Second, rather than using the observers conscious response as the
dependent variable, we use the early brain responses as measured by EEG. These
early responses cover a period where the observer is not yet conscious of the
quantum event. Results support the 'subjective reduction' hypothesis because
significant differences between the brain responses of the final observer are
found dependent upon the pre-observer looking or not looking at the quantum
event (exact binomial p < 0.02). Alternative 'normal' explanations are
discussed and rejected. It is concluded that the present results do justify
further research along these lines.Comment: 11 pages, 4 figures, 1 tabl
Sequential Least-Squares Using Orthogonal Transformations
Square root information estimation, starting from its beginnings in least-squares parameter estimation, is considered. Special attention is devoted to discussions of sensitivity and perturbation matrices, computed solutions and their formal statistics, consider-parameters and consider-covariances, and the effects of a priori statistics. The constant-parameter model is extended to include time-varying parameters and process noise, and the error analysis capabilities are generalized. Efficient and elegant smoothing results are obtained as easy consequences of the filter formulation. The value of the techniques is demonstrated by the navigation results that were obtained for the Mariner Venus-Mercury (Mariner 10) multiple-planetary space probe and for the Viking Mars space mission
A parameter estimation subroutine package
Linear least squares estimation and regression analyses continue to play a major role in orbit determination and related areas. A library of FORTRAN subroutines were developed to facilitate analyses of a variety of estimation problems. An easy to use, multi-purpose set of algorithms that are reasonably efficient and which use a minimal amount of computer storage are presented. Subroutine inputs, outputs, usage and listings are given, along with examples of how these routines can be used. The routines are compact and efficient and are far superior to the normal equation and Kalman filter data processing algorithms that are often used for least squares analyses
Integration-free interval doubling for Riccati equation solutions
Various algorithms are given for the case of constant coefficients. The algorithms are based on two ideas: first, relate the Re solution with general initial conditions to anchored RE solutions; and second, when the coefficients are constant the anchored solutions have a basic shift-invariance property. These ideas are used to construct an integration free superlinearly convergent iterative solution to the algebraic RE. The algorithm, arranged in square-root form, is thought to be numerically stable and competitive with other methods of solving the algebraic RE
A numerical comparison of discrete Kalman filtering algorithms: An orbit determination case study
The numerical stability and accuracy of various Kalman filter algorithms are thoroughly studied. Numerical results and conclusions are based on a realistic planetary approach orbit determination study. The case study results of this report highlight the numerical instability of the conventional and stabilized Kalman algorithms. Numerical errors associated with these algorithms can be so large as to obscure important mismodeling effects and thus give misleading estimates of filter accuracy. The positive result of this study is that the Bierman-Thornton U-D covariance factorization algorithm is computationally efficient, with CPU costs that differ negligibly from the conventional Kalman costs. In addition, accuracy of the U-D filter using single-precision arithmetic consistently matches the double-precision reference results. Numerical stability of the U-D filter is further demonstrated by its insensitivity of variations in the a priori statistics
A parameter estimation subroutine package
Linear least squares estimation and regression analyses continue to play a major role in orbit determination and related areas. FORTRAN subroutines have been developed to facilitate analyses of a variety of parameter estimation problems. Easy to use multipurpose sets of algorithms are reported that are reasonably efficient and which use a minimal amount of computer storage. Subroutine inputs, outputs, usage and listings are given, along with examples of how these routines can be used
A parameter estimation subroutine package
Linear least squares estimation and regression analyses continue to play a major role in orbit determination and related areas. In this report we document a library of FORTRAN subroutines that have been developed to facilitate analyses of a variety of estimation problems. Our purpose is to present an easy to use, multi-purpose set of algorithms that are reasonably efficient and which use a minimal amount of computer storage. Subroutine inputs, outputs, usage and listings are given along with examples of how these routines can be used. The following outline indicates the scope of this report: Section (1) introduction with reference to background material; Section (2) examples and applications; Section (3) subroutine directory summary; Section (4) the subroutine directory user description with input, output, and usage explained; and Section (5) subroutine FORTRAN listings. The routines are compact and efficient and are far superior to the normal equation and Kalman filter data processing algorithms that are often used for least squares analyses
Joint Report of Peer Review Panel for Numeric Nutrient Criteria for the Great Bay Estuary New Hampshire Department of Environmental Services June, 2009
This peer review was authorized through a collaborative agreement sponsored by the New Hampshire Department of Environmental Services (DES) and the Cities of Dover, Rochester and Portsmouth, New Hampshire. The purpose was to conduct an independent scientific peer review of the document entitled, “Numeric Nutrient Criteria for the Great Bay Estuary,” dated June, 2009 (DES 2009 Report)
Atomistic study of electronic structure of PbSe nanowires
Lead Selenide (PbSe) is an attractive `IV-VI' semiconductor material to
design optical sensors, lasers and thermoelectric devices. Improved fabrication
of PbSe nanowires (NWs) enables the utilization of low dimensional quantum
effects. The effect of cross-section size (W) and channel orientation on the
bandstructure of PbSe NWs is studied using an 18 band tight-binding
theory. The bandgap increases almost with the inverse of the W for all the
orientations indicating a weak symmetry dependence. [111] and [110] NWs show
higher ballistic conductance for the conduction and valence band compared to
[100] NWs due to the significant splitting of the projected L-valleys in [100]
NWs.Comment: 4 figures, Prepared for AP
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