34 research outputs found
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Uzbekistan Radiation Portal Monnitoring System
The work proposed in this presentation builds on the foundation set by the DTRA funded demonstration project begun in 2000 and completed in December of 2003. This previous work consisted of two phases whose overall objective was to install portal radiation monitors at four select ports-of-entry in Uzbekistan (Tashkent International Airport, Gisht-Kuprik (Kazakhstan border), Alat (Turkmenistan border), and Termez (Afghanistan border)) in order to demonstrate their effectiveness in preventing the illicit trafficking of nuclear materials. The objectives also included developing and demonstrating capabilities in the design, installation, operation, training, and maintenance of a radiation portal monitoring system. The system and demonstration project has proved successful in many ways. An effective working relationship among the Uzbekistan Customs Services, Uzbekistan Border Guards, and Uzbekistan Institute of Nuclear Physics has been developed. There has been unprecedented openness with the sharing of portal monitor data with Lawrence Livermore National Laboratory. The system has proved to be effective, with detection of illicit trafficking, and, at Alat, an arrest of three persons illegally transporting radioactive materials into Turkmenistan. The demonstration project has made Uzbekistan a model nonproliferation state in Central Asia and, with an expanded program, places them in a position to seal a likely transit route for illicit nuclear materials. These results will be described. In addition, this work is currently being expanded to include additional ports-of-entry in Uzbekistan. The process for deciding on which additional ports-of-entry to equip will also be described
Arnold diffusion for a complete family of perturbations
In this work we illustrate the Arnold diffusion in a concrete example — the a priori unstable Hamiltonian system of 2 + 1/2 degrees of freedom H(p, q, I, f, s) = p2/2+ cos q - 1 + I2/2 + h(q, f, s; e) — proving that for any small periodic perturbation of the form h(q, f, s; e) = e cos q (a00 + a10 cosf + a01 cos s) (a10a01 ¿ 0) there is global instability for the action. For the proof we apply a geometrical mechanism based on the so-called scattering map. This work has the following structure: In the first stage, for a more restricted case (I* ~ p/2µ, µ = a10/a01), we use only one scattering map, with a special property: the existence of simple paths of diffusion called highways. Later, in the general case we combine a scattering map with the inner map (inner dynamics) to prove the more general result (the existence of instability for any µ). The bifurcations of the scattering map are also studied as a function of µ. Finally, we give an estimate for the time of diffusion, and we show that this time is primarily the time spent under the scattering map.Peer ReviewedPostprint (published version
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A Monte Carlo Model for Interrogation of Thick Cargos for Clandestine Fissionable Materials; Tests with 14-MeV Neutrons
A Monte Carlo model has been developed for interrogation of fissionable material embedded in thick cargos when high-energy {beta}-delayed {gamma} rays are detected following neutron-induced fission. The model includes the principal structural components of the laboratory, the neutron source and collimator assembly in which it resides, the assembly that represents cargo of given characteristics, a target of highly-enriched uranium (HEU) and large external plastic scintillators for photon detection. The ability of this model to reproduce experimental measurements was tested by comparing simulations with measurements of the number of induced fissions and the number of detected photons when the HUE target was irradiated with 14.25-MeV neutrons in the absence of any cargo and while embedded in assemblies of plywood and iron pipes. The simulations agreed with experimental measurements within a factor of about 2 for irradiation of the bare target and when the areal density of intervening cargo was 33 g cm{sup -2} (wood) and 61 g cm{sup -2} (steel pipes). This suggests that the model can permit exploration of a large range in parameter space with reasonable fidelity
Ultrafast imaging method to measure surface tension and viscosity of inkjet-printed droplets in flight
Manual on Metric Building Drawing Practice
This manual, prepared by the Working Group of the Subcommittee on Design and Construction of the Interdepartmental Committee on Metric Conversion, has been developed to assist in the preparation of proper construction drawings that are so essential to a smooth transition. This Manual is a basic tool for metric conversion. The first three Parts explain what is involved in this conversion. Part 4 gives a step-by-step procedure for the production of metric drawings; the following Parts will assist, it is hoped, in design decisions and offer help with the actual "translating" of a design approach to metric.Ce manuel, pr\ue9par\ue9 par le Groupe de travail du Sous-comit\ue9 de conception et de construction du Comit\ue9 interminist\ue9riel de conversion m\ue9trique a \ue9t\ue9 \ue9labor\ue9 afin d'assister \ue0 la pr\ue9 paration des dessins de constructions appropri\ue9s qui sont essentiels \ue0 une transition ordonn\ue9e. Ce manuel est un ouvrage de base pour la conversion m\ue9trique. Les trois premi\ue8res parties expliquent ce qui est impliqu\ue9 dans cette conversion. La partie 4 donne une m\ue9thode \ue9tape de production des dessins m\ue9triques; il est souhait\ue9 que les parties suivantes aideront les d\ue9cisions de calcul et pourront offrir de l'aide dans la "traduction" d'une approche au calcul en utilisant le syst\ue8me m\ue9trique.Peer reviewed: NoNRC publication: Ye