Relevance and truthfulness in information correction and fusion

A general approach to information correction and fusion for belief functions is proposed, where not only may the information items be irrelevant, but sources may lie as well. We introduce a new correction scheme, which takes into account uncertain metaknowledge on the source’s relevance and truthfulness and that generalizes Shafer’s discounting operation. We then show how to reinterpret all connectives of Boolean logic in terms of source behavior assumptions with respect to relevance and truthfulness. We are led to generalize the unnormalized Dempster’s rule to all Boolean connectives, while taking into account the uncertainties pertaining to assumptions concerning the behavior of sources. Eventually, we further extend this approach to an even more general setting, where source behavior assumptions do not have to be restricted to relevance and truthfulness.We also establish the commutativity property between correction and fusion processes, when the behaviors of the sources are independent.

Pattern stability and error correction during in-phase and antiphase four-ball juggling

The authors studied pattern stability and error correction during in-phase and antiphase 4-ball fountain juggling. To obtain ball trajectories, they made and digitized high-speed film recordings of 4 highly skilled participants juggling at 3 different heights (and thus different frequencies). From those ball trajectories, the authors determined and analyzed critical events (i.e., toss, zenith, catch, and toss onset) in terms of variability of point estimates of relative phase and temporal correlations. Contrary to common findings on basic instances of rhythmic interlimb coordination, in-phase and antiphase patterns were equally variable (i.e., stable). Consistent with previous findings, however, pattern stability decreased with increasing frequency. In contrast to previous results for 3-ball cascade juggling, negative lag-one correlations for catch-catch intervals were absent, but the authors obtained evidence for error corrections between catches and toss onsets. That finding may have reflected participants' high skill level, which yielded smaller errors that allowed for corrections later in the hand cycle.

A correction to the analytical solution of the mixed-mode bending (MMB) problem

This paper addresses the analytical solution of the mixed-mode bending (MMB) problem. The first published solutions used a load separation in pure mode I and mode II and were applied for a crack length less than the beam half-span, a <= L. In later publications, the same mode separation was used in deriving the analytical solution for crack lengths bigger than the beam half-span, a > L. In this paper it is shown that this mode separation is not valid when a > L and in some cases may lead to very erroneous results. The correct mode separation and the corresponding analytical solutions, when a > L, are presented. Results, of force vs. displacement and force vs. crack length graphs, obtained using the existing formulation and the corrected formulation are compared. A finite element solution, which does not use mode separation, is also presented

Human pose tracking in low dimensional space enhanced by limb correction

This paper proposes a two-level 3D human pose tracking method for a specific action captured by several cameras. The generation of pose estimates relies on fitting a 3D articulated model on a Visual Hull generated from the input images. First, an initial pose estimate is constrained by a low dimensional manifold learnt by Temporal Laplacian Eigenmaps. Then, an improved global pose is calculated by refining individual limb poses. The validation of our method uses a public standard dataset and demonstrates its accurate and computational efficiency. © 2011 IEEE.

Towards Multi-Sensor Spectral Alignment Through Post Measurement Calibration Correction

Semiconductor manufactures are increasing reliant on optical emission spectroscopy (OES) to source information on plasma characteristics and process change. However, nonlinearities in the response of OES sensors and errors in their calibration lead to discrepancies in observed wavelength detector response. This paper presents a technique for the retrospective spectral calibration of multiple OES sensors. Underlying methodology is given, and alignment performance is evaluated using OES recordings from a semiconductor plasma process. The paper concludes with a discussion of results and suggests avenues for future work.

Cable correction of membrane currents recorded from root hairs of Arabidopsis thaliana L.

Membrane currents were recorded under voltage clamp from root hairs of Arabidopsis thaliana L. using the two-electrode method. Concurrent measurements of membrane voltage distal to the point of current injection were also carried out to assess the extent of current dissipation along the root hair axis. Estimates of the characteristic cable length, λ, showed this parameter to be a function both of membrane voltage and of substrate concentration for transport. The mean value for λ at 0 mV was 103 ± 20 μm (n=17), but ranged by as much as 6-fold in any one cell for membrane voltages from -300 to +40 mV and was affected by 0.25 to 3-fold at any one voltage on raising [K⁺]₀ from 0.1 to 10 mol m^-3. Current dissipation along the length of the cells lead to serious distortions of the current-voltage [I-V) characteristic, including consistent underestimates of membrane current as well as a general linearization of the I-V curve and a masking of conductance changes in the presence of transported substrates. In some experiments, microelectrodes were also placed in neighbouring epidermal cells to record the extent of intercellular coupling. Even with current-passing microelectrodes placed at the base of root hairs, coupling was ≤5% (voltage deflection of the epidermal cell ≤5% that recorded at the site of current injection), indicating an appreciable resistance to current passage between cells. These results demonstrate the feasibility of using root hairs as a 'single-cell model' in electrophysiological analyses of transport across the higher-plant plasma membrane; they also confirmed the need to correct for the cable properties of these cells on a cell-by-cell basis. © 1994 Oxford University Press.

Statistical data correction for unreliable memories

In this paper, we introduce a statistical data-correction framework that aims at improving the DSP system performance in presence of unreliable memories. The proposed signal processing framework implements best-effort error mitigation for signals that are corrupted by defects in unreliable storage arrays using a statistical correction function extracted from the signal statistics, a data-corruption model, and an application-specific cost function. An application example to communication systems demonstrates the efficacy of the proposed approach.

Correction of moderate myopia is associated with improvement in self-reported visual functioning among Mexican school-aged children.

PURPOSE: To quantify the impact on self-reported visual functioning of spectacle provision for school-aged children in Oaxaca, Mexico. METHODS: The Refractive Status Vision Profile (RSVP), a previously validated tool to measure the impact of refractive correction on visual functioning, was adapted for use in rural children and administered at baseline and 4 weeks (27.3 +/- 4.4 days) after the provision of free spectacles. Visual acuity with and without correction, age, sex, and spherical equivalent refraction were recorded at the time of follow-up. RESULTS: Among 88 children (mean age, 12 years; 55.7% girls), the median presenting acuity (uncorrected or with original spectacles), tested 4 weeks after the provision of free spectacles, was 6/9 (range, 6/6-6/120). Significant improvements in the following subscales of the RSVP were seen for the group as a whole after the provision of free spectacles: function, 11.2 points (P = 0.0001); symptoms, 14.3 points (P < 0.0001); total score, 10.3 points (P = 0.0001). After stratification by presenting vision in the better-seeing eye, children with 6/6 acuity (n = 22) did not have significant improvement in any subscale; those with acuity of 6/7.5 to 6/9 (n = 34) improved only on function (P = 0.02), symptoms (P = 0.005), and total score (P = 0.003); and those with acuity of 6/12 or worse improved on total score (P < 0.0001) and all subscales. Subjects (n = 31) with uncorrected myopia of -1.25 D or more had a mean improvement in total score of 15.9 points (P < 0.0001), whereas those with uncorrected myopia between -0.50 and -1.00 D inclusive (n = 53) had a mean improvement of 8 points (P = 0.01). CONCLUSIONS: Provision of spectacles to children in this setting had a significant impact on self-reported function, even at modest levels of baseline visual disability. The correlation between presenting vision/refraction and improvement and the failure of children 6/6 at baseline to improve offer evidence for a real effect.

Self correction of refractive error among young people in rural China: results of cross sectional investigation.

OBJECTIVE: To compare outcomes between adjustable spectacles and conventional methods for refraction in young people. DESIGN: Cross sectional study. SETTING: Rural southern China. PARTICIPANTS: 648 young people aged 12-18 (mean 14.9 (SD 0.98)), with uncorrected visual acuity ≤ 6/12 in either eye. INTERVENTIONS: All participants underwent self refraction without cycloplegia (paralysis of near focusing ability with topical eye drops), automated refraction without cycloplegia, and subjective refraction by an ophthalmologist with cycloplegia. MAIN OUTCOME MEASURES: Uncorrected and corrected vision, improvement of vision (lines on a chart), and refractive error. RESULTS: Among the participants, 59% (384) were girls, 44% (288) wore spectacles, and 61% (393/648) had 2.00 dioptres or more of myopia in the right eye. All completed self refraction. The proportion with visual acuity ≥ 6/7.5 in the better eye was 5.2% (95% confidence interval 3.6% to 6.9%) for uncorrected vision, 30.2% (25.7% to 34.8%) for currently worn spectacles, 96.9% (95.5% to 98.3%) for self refraction, 98.4% (97.4% to 99.5%) for automated refraction, and 99.1% (98.3% to 99.9%) for subjective refraction (P = 0.033 for self refraction v automated refraction, P = 0.001 for self refraction v subjective refraction). Improvements over uncorrected vision in the better eye with self refraction and subjective refraction were within one line on the eye chart in 98% of participants. In logistic regression models, failure to achieve maximum recorded visual acuity of 6/7.5 in right eyes with self refraction was associated with greater absolute value of myopia/hyperopia (P<0.001), greater astigmatism (P = 0.001), and not having previously worn spectacles (P = 0.002), but not age or sex. Significant inaccuracies in power (≥ 1.00 dioptre) were less common in right eyes with self refraction than with automated refraction (5% v 11%, P<0.001). CONCLUSIONS: Though visual acuity was slightly worse with self refraction than automated or subjective refraction, acuity was excellent in nearly all these young people with inadequately corrected refractive error at baseline. Inaccurate power was less common with self refraction than automated refraction. Self refraction could decrease the requirement for scarce trained personnel, expensive devices, and cycloplegia in children's vision programmes in rural China.