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A power-balance model, with radiation losses from impurities and neutrals, gives a unified description of the density limit (DL) of the stellarator, the L-mode tokamak, and the reversed field pinch (RFP). The model predicts a Sudo-like scaling for the stellarator, a Greenwald-like scaling, , for the RFP and the ohmic tokamak, a mixed scaling, , for the additionally heated L-mode tokamak. In a previous paper (Zanca et al 2017 Nucl. Fusion 57 056010) the model was compared with ohmic tokamak, RFP and stellarator experiments. Here, we address the issue of the DL dependence on heating power in the L-mode tokamak. Experimental data from high-density disrupted L-mode discharges performed at JET, as well as in other machines, are taken as a term of comparison. The model fits the observed maximum densities better than the pure Greenwald limit.

The 2014–2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L–H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent measurements of fine-scale structures in the edge radial electric. Dimensionless scans of the core and pedestal confinement provide new information to elucidate the importance of the first wall material on the fusion performance. H-mode plasmas at ITER triangularity (H  =  1 at βN ~ 1.8 and n/nGW ~ 0.6) have been sustained at 2 MA during 5 s. The ITER neutronics codes have been validated on high performance experiments. Prospects for the coming D–T campaign and 14 MeV neutron calibration strategy are reviewed.

BackgroundThere has been considerable work on tracking systems, for example, see [11] [9]. Our system draws ideas from these and other earlier work. While many of the basic ideas are similar, the details are often quite different, and are what account for the systems unique abilities.Some of the major differences stem from our area of application. Our goal is to track targets in a perimeter security type setting, i.e. outdoor operation in area of moderate to high cover. We seek real-time algorithms suitable for COTS (Common-Off-The-Sheff) type of computing, and use x86 based processors. This domain of application significantly restricts the techniques that can be applied. Some of the conThis work supported in part by DARPA Image Understanding's VSAM program. straints, and their implications for our systems include:The lighting is naturally varying. We must handle sunlight filtered through trees and intermittent cloud cover. (We are not considering IR cameras, yet).Targets use camouflage, thus it is unlikely that color will add much information. Figure 3 shows an example scene with a sniper in the grass.Targets will be moving in areas with large amounts of occlusion; finding/classifying outlines will be difficult.Trees/brush/clouds all move. The system must have algorithms to help distinguish these "insignificant" motions from target motions.Many targets will move slowly (less than [1/ 60] pixel per frame); some will move even more slowly. Some will try very hard to blend into the motion of the trees/brush. Therefore frame-to-frame differencing is of limited value. Temporal adaption schemes must not add slow targets to the background.Targets will not, in general, be "upright" or isolated. Thus we have not added "labeling" of targets based on simple shape/scale/orientation models.Targets need to be detected quickly and when they are still very small and distant, e.g. about 10-20 pixels on target.Correlation, template matching, and related techniques cannot be effectively used because of large amounts of occlusion and because in a paraimage, image translation is a very poor model; objects translating in the world undergo rotation and non-linear scaling.Note that, except for the last, these are all generic problem constraints and are not dependent on the geometry of the paraimage. If a system can track under these constraints it can be used in many situations, not just omni-directional tracking in outdoor settings.We also note that, the detection phase is crucial; if targets are not detected they will not be tracked. Detection is also an area where the domain constraints make this more difficult than the situtations considered in most past papers. As a result, much of this paper (and the systems effort) is concentrated on the detection phase. Because of the camouflage and 1

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By analyzing large quantities of discharges in the unfavorable ion B ×∇B drift direction, the I-mode operation has been confirmed in EAST tokamak. During the L-mode to I-mode transition, the energy confinement has a prominent improvement by the formation of a high-temperature edge pedestal, while the particle confinement remains almost identical to that in the L-mode. Similar with the I-mode observation on other devices, the E r profiles obtained by the eight-channel Doppler backscattering system (DBS8)[1] show a deeper edge E r well in the I-mode than that in the L-mode. And a weak coherent mode (WCM) with the frequency range of 40-150 kHz is observed at the edge plasma with the radial extend of about 2-3 cm. WCM could be observed in both density fluctuation and radial electric field fluctuation, and the bicoherence analyses showed significant couplings between WCM and high frequency turbulence, implying that the E r fluctuation and the caused flow shear from WCM should play an important role during I-mode. In addition, a low-frequency oscillation with a frequency range of 5-10 kHz is always accompanied with WCM, where GAM intensity is decreased or disappeared. Many evidences show that the a low-frequency oscillation may be a arXiv:1902.04750v3 [physics.plasm-ph]