LCrowdV: Generating Labeled Videos for Simulation-based Crowd Behavior Learning

We present a novel procedural framework to generate an arbitrary number of labeled crowd videos (LCrowdV). The resulting crowd video datasets are used to design accurate algorithms or training models for crowded scene understanding. Our overall approach is composed of two components: a procedural simulation framework for generating crowd movements and behaviors, and a procedural rendering framework to generate different videos or images. Each video or image is automatically labeled based on the environment, number of pedestrians, density, behavior, flow, lighting conditions, viewpoint, noise, etc. Furthermore, we can increase the realism by combining synthetically-generated behaviors with real-world background videos. We demonstrate the benefits of LCrowdV over prior lableled crowd datasets by improving the accuracy of pedestrian detection and crowd behavior classification algorithms. LCrowdV would be released on the WWW

Detailed comparison of the pp -> \pi^+pn and pp -> \pi^+d reactions at 951 MeV

The positively charged pions produced in proton-proton collisions at a beam momentum of 1640 MeV/c were measured in the forward direction with a high resolution magnetic spectrograph. The missing mass distribution shows the bound state (deuteron) clearly separated from the $pn$ continuum. Despite the very good resolution, there is no evidence for any significant production of the $pn$ system in the spin-singlet state. However, the $\sigma(pp\to \pi^+pn)/\sigma(pp\to \pi^+d)$ cross section ratio is about twice as large as that predicted from $S$-wave final-state-interaction theory and it is suggested that this is due to $D$-state effects in the $pn$ system.Comment: 8 pages, 3 figure

Small eta-N scattering lengths favour eta-d and eta-alpha states

Unstable states of the eta meson and the 3He nucleus predicted using the time delay method were found to be in agreement with a recent claim of eta-mesic 3He states made by the TAPS collaboration. Here, we extend this method to a speculative study of the unstable states occurring in the eta-d and eta-4He elastic scattering. The T-matrix for eta-4He scattering is evaluated within the Finite Rank Approximation (FRA) of few body equations. For the evaluation of time delay in the eta-d case, we use a parameterization of an existing Faddeev calculation and compare the results with those obtained from FRA. With an eta-N scattering length, $a_{\eta N} = (0.42, 0.34)$ fm, we find an eta-d unstable bound state around -16 MeV, within the Faddeev calculation. A similar state within the FRA is found for a low value of $a_{\eta N}$, namely, $a_{\eta N} = (0.28, 0.19)$ fm. The existence of an eta-4He unstable bound state close to threshold is hinted by $a_{\eta N} = (0.28, 0.19)$ fm, but is ruled out by large scattering lengths.Comment: 21 pages, LaTex, 7 Figure

Roadmap for Computer-Aided Modeling of Theranostics and Related Nanosystems

Detailed understanding of the interactions of novel metal-containing nanoparticles with biological membranes, macromolecules and other molecular targets of the living cell is crucial for the elucidation of the biological actions of such functionalized nanosystems. We present here the construction and modeling of thiolate-protected gold clusters and the prediction of their static and dynamic properties

Revealing the origins of vortex cavitation in a Venturi tube by high speed X-ray imaging

Hydrodynamic cavitation is useful in many processing applications, for example, in chemical reactors, water treatment and biochemical engineering. An important type of hydrodynamic cavitation that occurs in a Venturi tube is vortex cavitation known to cause luminescence whose intensity is closely related to the size and number of cavitation events. However, the mechanistic origins of bubbles constituting vortex cavitation remains unclear, although it has been concluded that the pressure fields generated by the cavitation collapse strongly depends on the bubble geometry. The common view is that vortex cavitation consists of numerous small spherical bubbles. In the present paper, aspects of vortex cavitation arising in a Venturi tube were visualized using high-speed X-ray imaging at SPring-8 and European XFEL. It was discovered that vortex cavitation in a Venturi tube consisted of angulated rather than spherical bubbles. The tangential velocity of the surface of vortex cavitation was assessed considering the Rankine vortex model

A precision determination of the mass of the η\eta meson

Several processes of meson production in proton-deuteron collisions have been measured simultaneously using a calibrated magnetic spectrograph. Among these processes, the $\eta$ meson is seen clearly as a sharp missing--mass peak on a slowly varying background in the $p+d\to ^3\textrm{He} +X$ reaction. Knowing the kinematics of the other reactions with well determined masses, it is possible to deduce a precise mass for the $\eta$ meson. The final result, $m(\eta)=547.311\pm 0.028 \textrm{(stat)} \pm 0.032 \textrm{(syst) MeV/c}^2$, is significantly lower than that found by the recent NA48 measurement, though it is consistent with values obtained in earlier counter experiments.Comment: 10 pages, 6 figures, Fig. 3 change

Virtual reality crowd simulation: effects of agent density on user experience and behaviour

Agent-based crowd simulations are used for modelling building and space usage, allowing designers to explore hypothetical real-world scenarios, including extraordinary events such as evacuations. Existing work which engages virtual reality (VR) as a platform for crowd simulations has been primarily focussed on the validation of simulation models through observation; the use of interactions such as gaze to enhance a sense of immersion; or studies of proxemics. In this work, we extend previous studies of proxemics and examine the effects of varying crowd density on user experience and behaviour. We have created a simulation in which participants walk freely and perform a routine manual task, whilst interacting with agents controlled by a typical social force simulation model. We examine and report the effects of crowd density on both affective state and behaviour. Our results show a significant increase in negative affect with density, measured using a self-report scale. We further show significant differences in some aspects of user behaviours, using video analysis, and discuss how our results relate to VR simulation design for mixed human–agent scenarios

On the Automatic Generation of an OWL Ontology based on the Joint C3 Information Exchange Data Model" ms

Abstract. The JC3IEDM is a data model intended for the exchange of command, control and communication information. It is available as an ERwin data model for which there is an XML-based description of all entities, attributes, relations and codes, making it ripe for translation by XSLT. This paper describes the development of a set of transformation scripts that convert the JC3IEDM data model into an OWL ontology; it explains the major challenges encountered and discusses a number of issues concerning the practical use of the resulting ontology. While the primary purpose of this work is to provide the basis for a semantically rich ontology for use in representing and reasoning about command, control and communication operations, it is also intended to serve as an example of a general approach for translating ERwin data models into OWL ontologies