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131.
Abstract— The current status of AC powder electroluminescent (ACPEL) displays is reviewed with particular emphasis given to color and lifetime. The printing of the displays in forward and reverse architectures is also discussed, in addition to the fabrication of ACPEL displays with interdigitated electrodes, and different types of ACPEL phosphors and materials for back electrodes, transparent conducting electrodes, binders, and dielectrics are considered. Furthermore, shape conformable and highly flexible ACPEL displays are surveyed.  相似文献   
132.
A systematic literature search was carried out to investigate the relationship between quick returns (i.e. 11.0 hours or less between two consecutive shifts) and outcome measures of health, sleep, functional ability and work–life balance. A total of 22 studies published in 21 articles were included. Three types of quick returns were differentiated (from evening to morning/day, night to evening, morning/day to night shifts) where sleep duration and sleepiness appeared to be differently affected depending on which shifts the quick returns occurred between. There were some indications of detrimental effects of quick returns on proximate problems (e.g. sleep, sleepiness and fatigue), although the evidence of associations with more chronic outcome measures (physical and mental health and work–life balance) was inconclusive.

Practitioner Summary: Modern societies are dependent on people working shifts. This study systematically reviews literature on the consequences of quick returns (11.0 hours or less between two shifts). Quick returns have detrimental effects on acute health problems. However, the evidence regarding effects on chronic health is inconclusive.  相似文献   

133.
This is the first systematic investigation into the assumptions of image fusion using regression Kriging (RK) – a geostatistical method – illustrated with Landsat MS (multispectral) and SPOT (Satellite Pour l’Observation de la Terre) panchromatic images. The efficiency of different linear regression and Kriging methods in the fusion process is examined by visual and quantitative indicators. Results indicate a trade-off between spectral fidelity and spatial detail preservation for the GLS (generalized least squares regression) and OLS (ordinary least squares regression) methods in the RK process: OLS methods preserve more spatial detail, while GLS methods retain more spectral information from the MS images but at a greater computational cost. Under either OK (ordinary Kriging) or UK (universal Kriging) with either OLS or GLS, the spherical variogram improves spatial details from the panchromatic image, while the exponential variogram maintains more spectral information from the MS image. Overall, RK-based fusion methods outperform conventional fusion approaches from both the spectral and spatial point of view.  相似文献   
134.
Using the classical Parzen window (PW) estimate as the target function, the sparse kernel density estimator is constructed in a forward-constrained regression (FCR) manner. The proposed algorithm selects significant kernels one at a time, while the leave-one-out (LOO) test score is minimized subject to a simple positivity constraint in each forward stage. The model parameter estimation in each forward stage is simply the solution of jackknife parameter estimator for a single parameter, subject to the same positivity constraint check. For each selected kernels, the associated kernel width is updated via the Gauss-Newton method with the model parameter estimate fixed. The proposed approach is simple to implement and the associated computational cost is very low. Numerical examples are employed to demonstrate the efficacy of the proposed approach.  相似文献   
135.
This paper reports on five different models of command and control. Four different models are reviewed: a process model, a contextual control model, a decision ladder model and a functional model. Further to this, command and control activities are analysed in three distinct domains: armed forces, emergency services and civilian services. From this analysis, taxonomies of command and control activities are developed that give rise to an activities model of command and control. This model will be used to guide further research into technological support of command and control activities.  相似文献   
136.
A brief history of robotic systems in knee arthroplasty is provided. The place of autonomous robots is then discussed and compared to more recent 'hands-on' robotic systems that can be more cost effective. The case is made for robotic systems to have a clear justification, with improved benefits compared to those from cheaper navigation systems. A number of more recent, smaller, robot systems for knee arthroplasty are also described. A specific example is given of an active constraint medical robot, the ACROBOT system, used in a prospective randomized controlled trial of unicondylar robotic knee arthroplasty in which the robot was compared to conventional surgery. The results of the trial are presented together with a discussion of the need for measures of accuracy to be introduced so that the efficacy of the robotic surgery can be immediately identified, rather than have to wait for a number of years before long-term clinical improvements can be demonstrated.  相似文献   
137.
The GIAO-SCF method for calculating isotropic nuclear magnetic shielding values has been utilized to explain certain features in the 1H-NMR spectrum of 2-methylene-8,8-dimethyl-1,4,6,10-tetraoxaspiro[4.5] decane. Population distributions of the low-energy conformers based on their ab initio energies were used to produce weighting factors for the individual calculated shielding values to calculate the weighted average of the shielding values for a complete set of conformers. The differences in 1H chemical shifts between the hydrogens of the two methyl groups and between the axial and equatorial hydrogens in 2-methylene-8,8-dimethyl-1,4,6,10-tetraoxaspiro[4.5] decane were shown to be due to energy differences between the chair and boat orientations of the six-membered ring and contribution from a twist-boat conformation. Results suggest a hypothesis that intramolecular differences in chemical shift might be calculated to a greater degree of accuracy than chemical shifts calculated relative to a standard.  相似文献   
138.
The value of Shuttle Imaging Radar images for the estimation of population is considered using a 1981 example for Tunisia. The results are compared with 1975 census data. The results show that the relationship of image areas to population is reasonably strong in areas where settlements are relatively small and have a uniform and low building density.  相似文献   
139.
The results of an investigation into the effects of the magnetic processing procedure on the intrinsic coercivity of a Sm(Co0.673Cu0.080Fe0.222Zr0.025)8.92 (217-type) alloy are reported. Two basic types of magnet were investigated: polymer-bonded fine powder magnets and cast (solid) magnets. The fine particles which were processed into polymer-bonded magnets were prepared by two different methods; i.e. by milling or by a hydrogen treatment. The cast magnets were manufactured from selected parts of solidified ingots exhibiting preferrred orientation and along directions parallel to the preferred orientation of magnetization. Magnetic properties and Vickers microhardness measurements on the solid solution treated (1170° C) and isothermally aged (800° C) samples, revealed that there was a clear similarity between the variations of the intrinsic coercivity and microhardness values versus ageing period. This suggests a coercivity mechanism for the present 217-type alloy which is predominantly controlled by general domain wall pinning by a critical dispersion of coherent precipitates. Certain aspects of the intrinsic coercivity against ageing time variations of the variously processed magnets as well as the corresponding microhardness variations have been attributed to a partial conversion of coherent precipitates to semi- or in-coherent particles during processing.  相似文献   
140.
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