Nonlinear predictive control of smooth nonlinear systems based on Volterra models. Application to a pilot plant

There is a large demand to apply nonlinear algorithms to control nonlinear systems. With algorithms considering the process nonlinearities, better control performance is expected in the whole operating range than with linear control algorithms. Three predictive control algorithms based on a Volterra model are considered. The iterative predictive control algorithm to solve the complete nonlinear problem uses the non‐autoregressive Volterra model calculated from the identified autoregressive Volterra model. Two algorithms for a reduced nonlinear optimization problem are considered for the unconstrained case, where an analytic control expression can be given. The performance of the three algorithms is analyzed and compared for reference signal tracking and disturbance rejection. The algorithms are applied and compared in simulation to control a Wiener model, and are used for real‐time control of a chemical pilot plant. Copyright © 2009 John Wiley & Sons, Ltd.     

Extracting 3D facial animation parameters from multiview video clips

We propose an accurate and inexpensive procedure that estimates 3D facial motion parameters from mirror-reflected multiview video clips. We place two planar mirrors near a subject's cheeks and use a single camera to simultaneously capture a marker's front and side view images. We also propose a novel closed-form linear algorithm to reconstruct 3D positions from real versus mirrored point correspondences in an uncalibrated environment. Our computer simulations reveal that exploiting mirrors' various reflective properties yields a more robust, accurate, and simpler 3D position estimation approach than general-purpose stereo vision methods that use a linear approach or maximum-likelihood optimization. Our experiments show a root mean square (RMS) error of less than 2 mm in 3D space with only 20-point correspondences. For semiautomatic 3D motion tracking, we use an adaptive Kalman predictor and filter to improve stability and infer the occluded markers' position. Our approach tracks more than 50 markers on a subject's face and lips from 30-frame-per-second video clips. We've applied the facial motion parameters estimated from the proposed method to our facial animation system.     

The contributions of human factors and ergonomics to a sustainable minerals industry

This article describes examples of the application of human factors research and development work to a sustainable minerals industry. It begins by outlining human-related aspects of the minerals industry and the key human factors work previously undertaken in this domain. The focus then switches to sustainability in the minerals industry. Sustainability principles are introduced and illustrations provided of how human factors research and development work fits within such a framework. Three case studies of human factors in the minerals industry research are presented and the sustainability implications in each case study are highlighted. Finally, future trends related to human factors work in a sustainable minerals industry are addressed, in particular the opportunities and possible adverse consequences that increasing deployment of mining automation might bring.

Practitioner Summary: Minerals industries are a major global activity with significant sustainability implications. Aspects of sustainability in mining are examined using three case studies. These illustrate the contribution of human factors/ergonomics in reducing risks; developing emergency response management systems; and the value of participatory ergonomics in improving the design of mining equipment.     

Applying artificial intelligence to virtual reality: Intelligent virtual environments

Research into virtual environments on the one hand and artificial intelligence and artificial life on the other has largely been carried out by two different groups of people with different preoccupation and interests, but some convergence is now apparent between the two fields. Applications in which activity independent of the user takes place- involving crowds or other agents- are beginning to be tackled, while synthetic agents, virtual humans, and computer pets are all areas in which techniques from the two fields require strong integration. The two communities have much to learn from each other if wheels are not to be reinvented on both sides. This paper reviews the issues arising from combining artificial intelligence and artificial life techniques with those of virtual environments to produce just such intelligent virtual environments. The discussion is illustrated with examples that include environments providing knowledge to direct or assist the user rather than relying entirely on the user's knowledge and skills, those in which the user is represented by a partially autonomous avatar, those containing intelligent agents separate from the user, and many others from both sides of the area.     

Recent progress in high‐efficiency phosphorescent OLED technology

Abstract— A key performance attribute for widespread commercialization of OLED technology is achieving maximum power efficiency along with color chromaticity and operational lifetime. Towards this goal, phosphorescent‐OLED (PHOLED) devices have demonstrated potential. Recent PHOLED device results show both excellent device efficiencies and long lifetimes towards the commercialization of low power consumption, full color, passive‐ and active‐matrix (both polysilicon and amorphous‐silicon backplane technologies) OLED displays.     

Fuzzy conceptual indexing for concept-based cross-lingual text retrieval

Cross-lingual text retrieval (CLTR) is a technique for locating relevant documents in different languages. The authors have developed fuzzy conceptual indexing (FCI) to extend CLTR to include documents that share concepts but don't contain exact translations of query terms. In FCI, documents and queries are represented as a function of language-independent concepts, thus enabling direct mapping between them across multiple languages. Experimental results suggest that concept-based CLTR outperforms translation-based CLTR in identifying conceptually relevant documents.     

Computation of through-space NMR shielding effects in aromatic ring pi-stacked complexes

Aromatic compounds can form dimeric complexes in solution. Substituted aromatics tend to form parallel-stacked complexes, either aligned or offset. The HF-GIAO method in Gaussian 03 was employed to calculate the NMR isotropic shielding values of the proximal hydrogen of diatomic hydrogen probes above and below the center of the ring and above and below an unsubstituted ring carbon of 1,3,5-trimethylbenzene in a face-to-face pi-stacked aligned complex with 1,3,5-trinitrobenzene. The calculated isotropic shielding values for the aromatic hydrogens of each of the substituted rings were subtracted from the isotropic shielding values calculated for the comparable positions in the complex. Complexation results in each aromatic ring shielding the other ring. Also, the calculated isotropic shielding values for the proximal hydrogen of a diatomic hydrogen probe over (or under) each of the individual substituted benzenes were subtracted from the isotropic shielding values calculated for the comparable positions in the complex. The difference is the shielding increment due to complexation. Complexation results in increased NMR shielding of a hydrogen probe molecule on both sides of the pi-stacked complex, with slightly more shielding due to complexation on the side nearest 1,3,5-trimethylbenzene. The results are interpreted in terms of polarization of the pi cloud of the substituted benzenes by complexation and its NMR consequences. Finally, NMR shielding calculations were done on the optimized structure of N-phenylpyrrole dimer. The data were compared to concentration-dependent NMR shift data to estimate the percent dimer present.     

Multilayer high-aspect-ratio RF coil for NMR applications

Microcoils offer a high degree of mass sensitivity and high magnetic field gradient strength in magnetic resonance microscopy applications. This paper presents a novel multilayer high-aspect-ratio metal fabrication process that can be used to fabricate a nanoliter-volume radio frequency (RF) saddle coil with an embedded flow-through fluidic channel for nuclear magnetic resonance (NMR) applications. The fabrication process is based on repeated electroplating processes and structure release processes. The achieved aspect ratio of the developed RF saddle coil is 4 with a structure line width of 25 μm. The resistance of the RF coil and the ¹H spectrum line width have been measured and are found to be 0.7 Ω and 350 Hz, respectively. Our results indicate that this novel fabrication process for RF microcoils is feasible for NMR applications.     

Effect of preozonation on organics coagulation removal from water

Abstract

The objective of this research was to study the effect of preozonation on a subsequent coagulation process when treating polluted surface waters. The results show for raw water containing only phenol, ozonation gives rise to more polar compounds, which are capable of forming hydrogen bonding or complexing among themselves or with hydrolytic products of the coagulants, so the organics removal may be enhanced. However, for raw water containing only humic acid, the effect of preozonation is insignificant. Furthermore, for the organic and clay mineral coexistence system, the hydrolytic products of co‐agulants may react preferentially with the ozonated organics; and turbidity removal is retarded. So, the effect of preozonation on coagulation depends on several factors, such as the type of dissolved organics, the existence of suspended solids, and the type and dosage of coagulants used.     

High-speed camera characterization of voluntary eye blinking kinematics

Blinking is vital to maintain the integrity of the ocular surface and its characteristics such as blink duration and speed can vary significantly, depending on the health of the eyes. The blink is so rapid that special techniques are required to characterize it. In this study, a high-speed camera was used to record and characterize voluntary blinking. The blinking motion of 25 healthy volunteers was recorded at 600 frames per second. Master curves for the palpebral aperture and blinking speed were constructed using palpebral aperture versus time data taken from the high-speed camera recordings, which show that one blink can be divided into four phases; closing, closed, early opening and late opening. Analysis of data from the high-speed camera images was used to calculate the palpebral aperture, peak blinking speed, average blinking speed and duration of voluntary blinking and compare it with data generated by other methods previously used to evaluate voluntary blinking. The advantages of the high-speed camera method over the others are discussed, thereby supporting the high potential usefulness of the method in clinical research.