Performance In Real Cases Research Articles

Highly Retentive, Anti-Interference, and Covert Individual Marking Taggant with Exceptional Skin Penetration.

The development of high‐performance individual marking taggants is of great significance. However, the interaction between taggant and skin is not fully understood, and a standard for marking taggants has yet to be realized. To achieve a highly retentive, anti‐interference, and covert individual marking fluorescent taggant, Mn2+‐doped NaYF4:Yb/Er upconversion nanoparticles (UCNPs), are surface‐functionalized with polyethyleneimine (PEI) to remarkably enhance the interaction between the amino groups and skin, and thus to facilitate the surface adhesion and chemical penetration of the taggant. Electrostatic interaction between PEI600‐UCNPs and skin as well as remarkable penetration inside the epidermis is responsible for excellent taggant retention capability, even while faced with robust washing, vigorous wiping, and rubbing for more than 100 cycles. Good anti‐interference capability and reliable marking performance in real cases are ensured by an intrinsic upconversion characteristic with a distinct red luminescent emission under 980 nm excitation. The present methodology is expected to shed light on the design of high‐performance individual marking taggants from the perspective of the underlying interaction between taggant and skin, and to help advance the use of fluorescent taggants for practical application, such as special character tracking.

A robust sub-pixel subdivision algorithm for image-type angular displacement measurement

The use of an image detector to receive grating images and measure angle displacement via image processing is a relatively new technique, which yields higher resolution and better precision than the traditional moiré fringe method. To improve the robustness of image-type angle measurement, this paper proposes a robust sub-pixel subdivision algorithm based on the least square method. Firstly, by analyzing the characteristic of grating image, a new subdivision algorithm is established based on the least square method. Secondly, the simulations of robustness are completed to prove the performance in theoretically. Lastly, the proposed algorithm is used in a typical image-type angle sensor to test the performance in real case. By test, the proposed method is shown to be more accurate and with better robust than the traditional algorithm (centroid algorithm). In a typical image-type angle sensor, it successfully achieves a resolution of 0.62″ (21-bit), 213-fold subdivision resolution, and precision of 12.85″. The results presented here may provide a theoretical and technological foundation for further research on small-size, high-resolution photographic rotary encoders.

Ensemble Kalman Filter data assimilation and storm surge experiments of tropical cyclone Nargis

Data assimilation experiments on Myanmar tropical cyclone (TC), Nargis, using the Local Ensemble Transform Kalman Filter (LETKF) method and the Japan Meteorological Agency (JMA) non-hydrostatic model (NHM) were performed to examine the impact of LETKF on analysis performance in real cases. Although the LETKF control experiment using NHM as its driving model (NHM–LETKF) produced a weak vortex, the subsequent 3-day forecast predicted Nargis’ track and intensity better than downscaling from JMA's global analysis. Some strategies to further improve the final analysis were considered. They were sea surface temperature (SST) perturbations and assimilation of TC advisories. To address SST uncertainty, SST analyses issued by operational forecast centres were used in the assimilation window. The use of a fixed source of SST analysis for each ensemble member was more effective in practice. SST perturbations were found to have slightly positive impact on the track forecasts. Assimilation of TC advisories could have a positive impact with a reasonable choice of its free parameters. However, the TC track forecasts exhibited northward displacements, when the observation error of intensities was underestimated in assimilation of TC advisories. The use of assimilation of TC advisories was considered in the final NHM–LETKF by choosing an appropriate set of free parameters. The extended forecast based on the final analysis provided meteorological forcings for a storm surge simulation using the Princeton Ocean Model. Probabilistic forecasts of the water levels at Irrawaddy and Yangon significantly improved the results in the previous studies.

Lessons from the Surgical Experience with Simulators: Incorporation into Training and Utilization in Determining Competency

Simulation technology in laparoscopic surgery has developed in response to a need to teach fundamental surgical skills in a safe environment. The skill set needed was defined carefully according to the classic educational model of needs assessment. Once defined, the skills were modeled in a simulator. The recognition that a simulator need not have high fidelity to achieve significant educational value was important in keeping costs reasonably low. Intrinsic to an effective simulation program is a set of metrics or measurements of performance. These metrics provide motivation for the student and allow comparison among students. Once shown to be reliable and valid, the simulator metrics can be used to set reasonable goals and standards for certification. Although simulators permit verification of learning, point simulation testing cannot by itself be used at present to ensure competence. Until the predictive value of these tests has been validated further, competence still needs to be determined by expert assessment of observed performance in real cases and by measurable outcome variables from real procedures. Simulation training is most beneficial when incorporated into a curriculum that teaches the accompanying knowledge and judgment essential for safe practice of the skills taught in the simulator. The FLS program distributed by the Society of American Gastrointestinal and Endoscopic Surgeons and the American College of Surgeons is an example of a carefully planned and validated program that incorporates these principles in laparoscopic surgery education. The lessons learned from development of the FLS program can be useful in designing a similar program for flexible gastrointestinal endoscopy.

Stability and consistency of children’s event recall

The purpose of the study was to investigate consistency of recall across different tasks of event recall (similar to eyewitness tasks) and stability of performance across two different events. Additionally, developmental differences in consistency and stability were explored. 6-, 8-, and 10-year-old children were subsequently shown two different events (videos) and were questioned about each event in two separate interviews. For both videos, performance levels in free recall, unbiased cued recall, and suggestibility were at similar levels, with older children generally outperforming younger children. As to intertask consistency of recall, there were significant correlations between correct free recall and correct unbiased cued recall but not between correct free recall and yielding to suggestive questions. All three measures of eyewitness performance showed significant group stability (test-retest correlations) across the two interviews, regardless of age. However, individual stability (lability) was lower, which points to moderate individual differences in stability across the two interviews. The findings are discussed in terms of underlying cognitive skills and the problem of predicting a single child’s memory performance in real cases of eyewitness testimony.