Exploring Causal Relationships in Visual Object Tracking

Causal relationships can often be found in visual object tracking between the motions of the camera and that of the tracked object. This object motion may be an effect of the camera motion, e.g. an unsteady handheld camera. But it may also be the cause, e.g. the cameraman framing the object. In this paper we explore these relationships, and provide statistical tools to detect and quantify them, these are based on transfer entropy and stem from information theory. The relationships are then exploited to make predictions about the object location. The approach is shown to be an excellent measure for describing such relationships. On the VOT2013 dataset the prediction accuracy is increased by 62 % over the best non-causal predictor. We show that the location predictions are robust to camera shake and sudden motion, which is invaluable for any tracking algorithm and demonstrate this by applying causal prediction to two state-of-the-art trackers. Both of them benefit, Struck gaining a 7 % accuracy and 22 % robustness increase on the VTB1.1 benchmark, becoming the new state-of-the-art

Real-time spectroscopy of solar pp neutrinos using Nd-150

The potential real-time spectroscopy of solar pp neutrinos using Nd-150 as target is investigated. The threshold of 196 keV would be the lowest of all solar neutrino experiments running so far. Experimental rates and parameters are discussed, about 580 SNU can be expected from pp-neutrinos and another 367 SNU from Be-7. Furthermore, it is investigated whether charged current reactions might cause a new background component for future double beta decay experiments based on a large amount of Nd-150.Comment: 9 pages, 1 figur

Positronic lithium, an electronically stable Li-e+^+ ground state

Calculations of the positron-Li system were performed using the Stochastic Variational Method and yielded a minimum energy of -7.53208 Hartree for the L=0 ground state. Unlike previous calculations of this system, the system was found to be stable against dissociation into the Ps + Li$^+$ channel with a binding energy of 0.00217 Hartree and is therefore electronically stable. This is the first instance of a rigorous calculation predicting that it is possible to combine a positron with a neutral atom and form an electronically stable bound state.Comment: 11 pages, 2 tables. To be published in Phys.Rev.Let

Distribution and ecology of wild lettuces Lactuca serriola L. and Lactuca virosa L. in central Chile

Wild lettuces (Lactuca L.) may provide valuable genetic resources for crop breeding, but are also significant invasive weeds. Monitoring populations of these species is important, therefore, both to inform genetic resource conservation efforts as well as for non-native plant species control. We explored the occurrences, distributions, and characteristics of populations of wild Lactuca species in central Chile through field surveys in 2016 and 2017, significantly adding to the available information on these species in the region. We documented two species - prickly lettuce (Lactuca serriola L.) and opium (bitter) lettuce (Lactuca virosa L.) in 204 localities. Occurrence only of L. serriola was recorded at 166 sites, only L. virosa at 21 sites, and both at 17 sites. Prickly lettuce was observed equally in urban areas and along transport corridors outside cities. Population sizes varied from a few plants to hundreds of individuals. Opium lettuce was recorded most frequently along roads outside cities, with population sizes of several individuals to a dozen. Species succession in different elevational gradients was observed along three roads: R 60 (Los Andes – Portillo), G-27 (Cajón Maipú), and 115 (Lago Colbún – Lago del Maule). These observations indicate that: i) both allochthonous (Euroasian) wild Lactuca species occur and are able to regenerate in central Chile; ii) L. serriola forms dense populations in urbanized areas; iii) both species can expand along transport corridors to high elevations; iv) the spread of L. virosa and persistence of dense populations in elevations above 2,000 m a.s.l. prove the invasiveness of this species in extreme climates; v) both species should be monitored (and treated) both in urbanized and agricultural areas, as well as in unique local mountainous areas

From Multiview Image Curves to 3D Drawings

Reconstructing 3D scenes from multiple views has made impressive strides in recent years, chiefly by correlating isolated feature points, intensity patterns, or curvilinear structures. In the general setting - without controlled acquisition, abundant texture, curves and surfaces following specific models or limiting scene complexity - most methods produce unorganized point clouds, meshes, or voxel representations, with some exceptions producing unorganized clouds of 3D curve fragments. Ideally, many applications require structured representations of curves, surfaces and their spatial relationships. This paper presents a step in this direction by formulating an approach that combines 2D image curves into a collection of 3D curves, with topological connectivity between them represented as a 3D graph. This results in a 3D drawing, which is complementary to surface representations in the same sense as a 3D scaffold complements a tent taut over it. We evaluate our results against truth on synthetic and real datasets.Comment: Expanded ECCV 2016 version with tweaked figures and including an overview of the supplementary material available at multiview-3d-drawing.sourceforge.ne

Commissioning of the vacuum system of the KATRIN Main Spectrometer

The KATRIN experiment will probe the neutrino mass by measuring the beta-electron energy spectrum near the endpoint of tritium beta-decay. An integral energy analysis will be performed by an electro-static spectrometer (Main Spectrometer), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m^3, and a complex inner electrode system with about 120000 individual parts. The strong magnetic field that guides the beta-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. A system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300{\deg}C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10^{-11} mbar range. It is demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.Comment: submitted for publication in JINST, 39 pages, 15 figure