3,213 research outputs found
Observations of galactic cosmic ray energy spectra between 1 and 9 AU
The variation of the 5 to 500 MeV/nuc cosmic ray helium component was studied between 1 and 9 A.U. using essentially identical detector systems on Pioneer 10 and 11 and Helios I. Between 100 and 200 MeV/nuc a radial gradient of 3.3?1.3%/A.U. is found. At 15 MeV/nuc this value increases to 20?4%/A.U. Between 4 and 9 A.U. a well defined intensity maximum is observed at approximately 17 MeV/nuc. The average adiabatic energy loss between 1 and 9 A.U. is approximately 4 MeV/nuc/A.U. The observed radial variation between 1 and 9 A.U. is well described by the Gleeson-Axford force field solution of the modulation equations over an energy range extending from 15 to 500 MeV/nuc and is in good agreement with the results reported by other Pioneer experiments. These values are much smaller than had been theoretically predicted
Simulation and analysis of complex human tasks
We discuss how the combination of a realistic human figure with a high-level behavioral control interface allow the construction of detailed simulations of humans performing manual tasks from which inferences about human performance requirements can be made. The Jack human modeling environment facilitates the real-time simulation of humans performing sequences of tasks such as walking, lifting, reaching, and grasping in a complex simulated environment. Analysis capabilities include strength, reachability, and visibility; moreover results from these tests can affect an unfolding simulation
Econometrics models for diagnostics of bank stability
The banking system - is one of the main parts of the market. Development of the commercial banks andthe banking system plays a major role in the financial life of the State [1]. We do analysis of the currentoperational state of the bank on a monthly, quarterly, annual balance sheets. It allows us to allocate risk. Ourprimary objective is to create automatic procedures for making comprehansive econometric analysis of bankstability. The nesessity of solving to this problem lies in the fact that such analysis optimizes bankers' work. Thatin turn will help to accelerate a putting into operation Basel III new reqirements. The econometric model we usecan serve us as an alarming system. In this work we focus on developing methods for determining the stability of the banks and constructing econometric model based on public information with multidimensional scaling [2]
Simulating Humans: Computer Graphics, Animation, and Control
People are all around us. They inhabit our home, workplace, entertainment, and environment. Their presence and actions are noted or ignored, enjoyed or disdained, analyzed or prescribed. The very ubiquitousness of other people in our lives poses a tantalizing challenge to the computational modeler: people are at once the most common object of interest and yet the most structurally complex. Their everyday movements are amazingly uid yet demanding to reproduce, with actions driven not just mechanically by muscles and bones but also cognitively by beliefs and intentions. Our motor systems manage to learn how to make us move without leaving us the burden or pleasure of knowing how we did it. Likewise we learn how to describe the actions and behaviors of others without consciously struggling with the processes of perception, recognition, and language
The Modified Weighted Slab Technique: Models and Results
In an attempt to understand the source and propagation of galactic cosmic
rays we have employed the Modified Weighted Slab technique along with recent
values of the relevant cross sections to compute primary to secondary ratios
including B/C and Sub-Fe/Fe for different galactic propagation models. The
models that we have considered are the disk-halo diffusion model, the dynamical
halo wind model, the turbulent diffusion model and a model with minimal
reacceleration. The modified weighted slab technique will be briefly discussed
and a more detailed description of the models will be given. We will also
discuss the impact that the various models have on the problem of anisotropy at
high energy and discuss what properties of a particular model bear on this
issue.Comment: LaTeX - AASTEX format, Submitted to ApJ, 8 figures, 20 page
Towards Personalities for Animated Agents With Reactive and Planning Behaviors
We describe a framework for creating animated simulations of virtual human agents. The framework allows us to capture flexible patterns of activity, reactivity to a changing environment, and certain aspects of an agent personality model. Each leads to variation in how an animated simulation will be realized. As different parts of an activity make different demands oil an agent\u27s resources and decision-making, our framework allows special-purpose reasoners and planners to be associated with only those phases of an activity where they are needed. Personality is reflected in locomotion choices which are guided by an agent model that interacts with the other components of the framework
Analytic Invariant Charge in QCD
This paper gives an overview of recently developed model for the QCD analytic
invariant charge. Its underlying idea is to bring the analyticity condition,
which follows from the general principles of local Quantum Field Theory, in
perturbative approach to renormalization group (RG) method. The concrete
realization of the latter consists in explicit imposition of analyticity
requirement on the perturbative expansion of function for the strong
running coupling, with subsequent solution of the corresponding RG equation. In
turn, this allows one to avoid the known difficulties originated in
perturbative approximation of the RG functions. Ultimately, the proposed
approach results in qualitatively new properties of the QCD invariant charge.
The latter enables one to describe a wide range of the strong interaction
processes both of perturbative and intrinsically nonperturbative nature.Comment: Invited review article; 46 pages, 14 EPS figure
Astrophysical Uncertainties in the Cosmic Ray Electron and Positron Spectrum From Annihilating Dark Matter
In recent years, a number of experiments have been conducted with the goal of
studying cosmic rays at GeV to TeV energies. This is a particularly interesting
regime from the perspective of indirect dark matter detection. To draw reliable
conclusions regarding dark matter from cosmic ray measurements, however, it is
important to first understand the propagation of cosmic rays through the
magnetic and radiation fields of the Milky Way. In this paper, we constrain the
characteristics of the cosmic ray propagation model through comparison with
observational inputs, including recent data from the CREAM experiment, and use
these constraints to estimate the corresponding uncertainties in the spectrum
of cosmic ray electrons and positrons from dark matter particles annihilating
in the halo of the Milky Way.Comment: 21 pages, 9 figure
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