2,286 research outputs found
Collider signatures of the SO(5) x U(1) gauge-Higgs unification
Collider signatures of the gauge-Higgs unification model
in the Randall-Sundrum warped space are explored. Gauge couplings of quarks and
leptons receive small corrections from the fifth dimension whose effects are
tested by the precision data. It is found that the forward-backward asymmetries
in collisions on the pole are well explained in a wide range of
the warp factor , but the model is consistent with the branching fractions
of decay only for large z_L \simg 10^{15}. Kaluza-Klein (KK) spectra of
gauge bosons, quarks, and leptons as well as gauge and Higgs couplings of
low-lying KK excited states are determined. Right-handed quarks and leptons
have larger couplings to the KK gauge bosons than left-handed ones. Production
rates of Higgs bosons and KK states at Tevatron, LHC and ILC are evaluated. The
first KK has a mass 1130 GeV with a width 422 GeV for . The
current limit on the production at Tevatron and LHC indicates . A large effect of parity violation appears in the difference between
the rapidity distributions of and in the decay of the first KK .
The first KK gauge bosons decay into light and heavy quarks evenly.Comment: 45 pages, 6 figures. Contributions from the first KK photon are taken
into accoun
Adaptive intermittent control: A computational model explaining motor intermittency observed in human behavior
It is a fundamental question how our brain performs a given motor task in a real-time fashion with the slow sensorimotor system. Computational theory proposed an influential idea of feed-forward control, but it has mainly treated the case that the movement is ballistic (such as reaching) because the motor commands should be calculated in advance of movement execution. As a possible mechanism for operating feed-forward control in continuous motor tasks (such as target tracking), we propose a control model called "adaptive intermittent control" or "segmented control," that brain adaptively divides the continuous time axis into discrete segments and executes feed-forward control in each segment. The idea of intermittent control has been proposed in the fields of control theory, biological modeling and nonlinear dynamical system. Compared with these previous models, the key of the proposed model is that the system speculatively determines the segmentation based on the future prediction and its uncertainty. The result of computer simulation showed that the proposed model realized faithful visuo-manual tracking with realistic sensorimotor delays and with less computational costs (i.e., with fewer number of segments). Furthermore, it replicated "motor intermittency", that is, intermittent discontinuities commonly observed in human movement trajectories. We discuss that the temporally segmented control is an inevitable strategy for brain which has to achieve a given task with small computational (or cognitive) cost, using a slow control system in an uncertain variable environment, and the motor intermittency is the side-effect of this strategy
Development of a video-rate range finder using dynamic threshold method for characteristic point detection
This study develops a video-rate stereo range finding circuit to obtain the depth of objects in a scene by processing video signals (R, G, B, and brightness signals) from binocular CCD cameras. The electronic circuit implements a dynamic threshold method to decrease the affect of signal noise in characteristic point detection, where a video signal from each CCD camera is compared with multiple thresholds, shifting dynamically by feeding back the previous comparison result. Several object depth measurement experiments for simple indoor scenes show that the dynamic threshold method gives high acquisition and correct rates of depth data compared with those by a fixed threshold method for the video signals and a relative method for R, G, and B signals utilized in the authors' previous range finders
Display of diagnostic information from multiple viewpoints in an anomalous situation of complex plants
The paper describes the objectives, approaches, and current status of an intelligent information display agent called semantic representation interface (SI). The SI displays diagnostic information from a functional viewpoint as well as from behavioral, operational, and structural ones to plant operators in an anomalous situation. The functional information of the plant will help operators to understand the overall plant situation and the necessity of a recommended counter action written in operation manuals or suggested by the SI. Diagnostic information of anomaly identification and finding possible counter actions are derived by qualitative reasoning based on a functional model. The selection of suitable counter actions which will be developed in the near future is made using a fast future prediction code generated by an intelligent modular simulation system. The derived diagnostic information is displayed in a graphical way so that an operator can understand the information as a pattern. In addition to the graphical display, necessary graphs to understand the plant situation and the derived diagnostic information are automatically shown. The applicability of the diagnostic techniques applied the qualitative reasoning is discussed through applications to an oil refinery plant</p
An Investigation on Low Frequency Combustion Oscillation
This paper deals with a combustion stability of diffusion flame. A simplified linear differential equation of second order, which involves the parameters estimated from the states of steady combustion, has been suggested to discuss
theoretically the nature of oscillatory combusion about a two-dimensional combustion chamber. Its validity has been testified by comparing calculated results with experimental ones. Results obtained have indicated that factors markedly affecting the low-frequency oscillatory combustion are primary volumetric air-fuel ratio, duct length of combustion side, shape of burner and inlet
throttles. But outlet throttle gives little effect on the stability of combustion
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