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Improved Performance (improved + performance)
Selected AbstractsEmbedded Shape-Memory Alloy Wires for Improved Performance of Self-Healing PolymersADVANCED FUNCTIONAL MATERIALS, Issue 17 2008Eva L. Kirkby No abstract is available for this article. [source] Embedded Shape-Memory Alloy Wires for Improved Performance of Self-Healing Polymers,ADVANCED FUNCTIONAL MATERIALS, Issue 15 2008Eva L. Kirkby Abstract We report the first measurements of self-healing polymers with embedded shape-memory alloy (SMA) wires. The addition of SMA wires shows improvements of healed peak fracture loads by up to a factor of 1.6, approaching the performance of the virgin material. Moreover, the repairs can be achieved with reduced amounts of healing agent. The improvements in performance are due to two main effects: (i) crack closure, which reduces the total crack volume and increases the crack fill factor for a given amount of healing agent and (ii) heating of the healing agent during polymerization, which increases the degree of cure of the polymerized healing agent. [source] Organic Electronics: Improved Performance of Polymer Bulk Heterojunction Solar Cells Through the Reduction of Phase Separation via Solvent Additives (Adv. Mater.ADVANCED MATERIALS, Issue 8 20108/2010) The fabrication of bulk heterojunction organic solar cells from solution-casting techniques using low-cost materials makes them a promising new technology for converting sunlight into electricity. T.-Q. Nguyen, G. C. Bazan, et al. report on p. E63 that undesirable large-scale aggregation and phase separation that may arise during deposition can be reduced by incorporating a small amount of a well-chosen solvent additive. [source] Suppressing One-Bond Correlations in HMBC Spectra: Improved Performance for the BIRD,HMBC Pulse SequenceMAGNETIC RESONANCE IN CHEMISTRY, Issue 3 2009Julien Furrer Abstract An improved version of the BIRD,HMBC experiment is proposed. In comparison to the original version, the filtering (suppression of 1JCH signals) is accomplished using a double tuned G-BIRD filter positioned in the middle of the long-range correlations evolution period. Compensation of offset dependence by replacing the rectangular 180° pulses with the broadband inversion pulses (BIPs), with superior inversion performance and improved tolerance to B1 field inhomogeneity, significantly improves the sensitivity of the original BIRD,HMBC experiment. For usual one-bond coupling constants ranges (115,180 Hz), optimal results are easily obtained by adjusting the delays, ,, of the BIRD elements to an average J value. For larger ranges (e.g. 110,260 Hz), the use of a double tuned G-BIRD filter allows excellent suppression degrees for all types of one-bond constants present in a molecule, superior to the original scheme and other purging schemes. These attributes make the improved version of the BIRD,HMBC experiment a valuable and robust tool for rapid spectral analysis and rapid checks of molecular skeletons with a minimum spectrometer time. Copyright © 2009 John Wiley & Sons, Ltd. [source] Should symptom frequency be factored into scalar measures of alcohol use disorder severity?ADDICTION, Issue 9 2010Deborah A. Dawson ABSTRACT Aims To evaluate whether weighting counts of alcohol use disorder (AUD) criteria or symptoms by their frequency of occurrence improves their association with correlates of AUD. Design and participants Data were collected in personal interviews with a representative sample of US adults interviewed in 1991,92. Analyses were conducted among past-year drinkers (12+ drinks, n = 18 352) and individuals with past-year DSM-IV AUD (n = 2770). Measurements Thirty-one symptom item indicators, whose frequency of occurrence was measured in eight categories, were used to create unweighted and frequency-weighted counts of DSM-IV past-year AUD symptoms and criteria. Correlates included density of familial alcoholism and past-year volume of ethanol intake, frequency of intoxication and utilization of alcohol treatment. Findings Although the AUD correlates were associated strongly and positively with the frequency of AUD symptom occurrence, weighting for symptom frequency did not strengthen their association consistently with AUD severity scores. Improved performance of the weighted scores was observed primarily among AUD correlates linked closely with the frequency of heavy drinking and among individuals with AUD. Criterion counts were correlated nearly as strongly as symptom counts with the AUD correlates. Conclusions Frequency weighting may add somewhat to the validity of AUD severity measures, especially those that are intended for use among individuals with AUD, e.g. in clinical settings. For studying the etiology and course of AUD in the general population, an equally effective and less time-consuming alternative to obtaining symptom frequency may be the use of unweighted criterion counts accompanied by independent measures of frequency of heavy drinking. [source] Feasibility of k-t BLAST technique for measuring "seven-dimensional" fluid flowJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2006Ian Marshall PhD Abstract Purpose To investigate the feasibility of rapid MR measurement of "seven-dimensional" (three velocity components, three dimensions, and time) fluid flow using the k-t Broad-use Linear Acquisition Speed-Up Technique (BLAST). Materials and Methods Complete k -space data were acquired for pulsatile fluid flow in a model of a stenosed carotid bifurcation. The data was subsampled to simulate "training" and "accelerated acquisition" data for reconstruction using k-t BLAST. Results Flow waveforms estimated from k-t BLAST reconstructions were in good agreement with those measured from the full data set for overall speedup factors up to approximately four times when slice-by-slice undersampling in ky was used. Accuracy was better than 25 mm/second or 7% (root-mean-square error) for individual time frames under these conditions. Flow patterns in the plane of symmetry, near the bifurcation, and in the stenosis were also in good agreement with those reconstructed from the full data set. Improved performance was obtained from undersampling in both ky and kz, when acceleration factors up to 12 times gave acceptable results. Conclusion The k-t BLAST technique can be applied to flow quantification, and may make feasible the acquisition of time-resolved blood flow from extended arterial regions within acceptable examination times. J. Magn. Reson. Imaging 2006. © 2006 Wiley-Liss, Inc. [source] Increased gas solubility in nanoliquids: Improved performance in interfacial catalytic membrane contactorsAICHE JOURNAL, Issue 2 2009Marc Pera-Titus Abstract The kinetics of gas-liquid catalytic reactions can be strongly promoted when these are performed in interfacial catalytic membrane reactors instead of other three-phase reactors such as slurry stirrers or trickle beds. The well-defined gas-liquid-catalyst contact in this system avoiding diffusional limitations is usually argued as the main reason for such enhancement. In this work, using nitrobenzene hydrogenation as a model reaction, we propose that this increased catalytic performance might also be attributed, at least partially, to increased gas solubilities in mesoconfined solvents (or simply "nanoliquids") in interfacial contactors overcoming the values predicted by Henry's Law. To support this hypothesis, we provide experimental evidence of a dramatic increase of H2 solubility in confined ethanol using mesoporous ,-Al2O3 as confining solid. Gas-liquid solubilities can be enhanced up to five times over the corresponding bulk values for nanoliquid sizes lower than 15 nm as long as the gas-liquid interface is confined in a mesoporous array. In such a situation, the volume of the gas-liquid interface is no longer negligible compared to the total volume of the confined liquid, and the high surface excess concentrations of the gas adsorbed on the liquid surface make solubility grow up dramatically. According to these measurements, we discuss how nanoliquids might form in catalytic membrane contactors, which gas-liquid configuration in the reactor appears to be more appropriate, and how the structure of the mesoporous catalytic layer contributes to their increased gas solubilization performance. © 2008 American Institute of Chemical Engineers AIChE J, 2009 [source] Enhanced performance by inserting ultrathin SiO2 layer in organic light-emitting devicesPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 3 2007Lianbin Niu Abstract Improved performance of organic light-emitting devices (OLEDs) has been obtained by insertion of an ultrathin film of silicon oxide (SiO2) at the interface of 8-hydroxyquinoline aluminum (Alq3) and N,N ,-bis(1-naphthyl)- N,N ,-diphenyl-1,1,-biphenyl-4,4,-diamine (NPB) layers. When a 1.0 nm SiO2 film was inserted, for an unoptimized indium,tin oxide (ITO)/NPB/SiO2/Alq3/Al device, the current efficiency was as high as 7.35 cd/A. Compared with conventional devices, a higher efficiency has been achieved. The mechanism of performance enhancement is discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Highest Density Difference Region Estimation with Application to Flow Cytometric DataBIOMETRICAL JOURNAL, Issue 3 2009Tarn Duong Abstract Motivated by the needs of scientists using flow cytometry, we study the problem of estimating the region where two multivariate samples differ in density. We call this problem highest density difference region estimation and recognise it as a two-sample analogue of highest density region or excess set estimation. Flow cytometry samples are typically in the order of 10,000 and 100,000 and with dimension ranging from about 3 to 20. The industry standard for the problem being studied is called Frequency Difference Gating, due to Roederer and Hardy (2001). After couching the problem in a formal statistical framework we devise an alternative estimator that draws upon recent statistical developments such as patient rule induction methods. Improved performance is illustrated in simulations. While motivated by flow cytometry, the methodology is suitable for general multivariate random samples where density difference regions are of interest. [source] A Structural Analysis of the Effectiveness of Buying Firms' Strategies to Improve Supplier PerformanceDECISION SCIENCES, Issue 1 2000Daniel R. Krause Many manufacturing firms have increased the amount of component parts and services they outsource, while refocusing on their core capabilities. Outsourcing parts and services to independent, external suppliers means that suppliers' performance is increasingly critical to the long-term success of these buying firms. Buying firms are increasingly using disparate supplier development strategies to improve supplier performance including supplier assessment, providing incentives for improved performance, instigating competition among suppliers, and direct involvement of the buying firm's personnel with suppliers through activities such as training of suppliers' personnel. Using resource-based theory, internalization theory, and structural equation modeling, we examine the impact of these supplier development strategies on performance. We conclude that direct involvement activities, where the buying firm internalizes a significant amount of the supplier development effort, play a critical role in performance improvement. [source] Ammonia Gas Sensor Using Polypyrrole-Coated TiO2/ZnO NanofibersELECTROANALYSIS, Issue 12 2009Ying Wang Abstract Highly porous polypyrrole (PPy)-coated TiO2/ZnO nanofibrous mat has been successfully synthesized. The core TiO2/ZnO nanofibers have an average diameter of ca. 100,nm and the shell of ultrathin PPy layer has a thickness of ca. 7,nm. The NH3 gas sensor using the as-prepared material exhibited a fast response over a wide dynamic range and high sensitivity with a detection limit of 60,ppb (S/N=3). Compared to conventional pristine PPy film, the improved performance in NH3 detection can be attributed to the free access of NH3 to PPy and a minimized gas diffusion resistance through the ultrathin PPy layer. [source] Fast track: Has it changed patient care in the emergency department?EMERGENCY MEDICINE AUSTRALASIA, Issue 1 2008Paul Kwa Abstract Objective: To determine whether the introduction of a designated fast-track area altered the time to care and patient flow in an Australian mixed adult and paediatric ED. Methods: Retrospective cohort study of all patients presenting to the ED between 08.00 and 22.00 hours, during a 6 month period before and after the opening of a fast-track area. Data were stratified according to Australasian Triage Scale (ATS) category, and comparisons were made for performance indicators, waiting time, length of stay and did-not-waits. Results: During its operational hours, fast track managed 14.9% of all patients presenting to the ED. There was a significant increase in the proportion of all ATS 4 patients seen within their target times (77.8% to 79.9%, P < 0.001). There was a trend towards improved performance in ATS categories 2, 3 and 5. Median patient waiting times were significantly decreased in ATS 4 (24 to 22 min, P < 0.001) and ATS 5 (27 to 25 min, P < 0.05), but increased in ATS 2 (3 to 4 min, P < 0.05). No deterioration in performance or waiting time for ATS 1 was shown. There was a decreasing trend in the proportion of patients who did not wait to be assessed by a doctor in ATS categories 4 and 5. These improvements occurred despite a 12% increase in patient attendances and no change in medical staffing levels. Conclusions: Fast track in an Australian mixed ED can help meet the demand of increasing patient attendances, allowing lower-acuity patients to be seen quickly without a negative impact on high-acuity patients. [source] High K Capacitors and OFET Gate Dielectrics from Self-Assembled BaTiO3 and (Ba,Sr)TiO3 Nanocrystals in the Superparaelectric LimitADVANCED FUNCTIONAL MATERIALS, Issue 4 2010Limin Huang Abstract Nanodielectrics is an emerging field with applications in capacitors, gate dielectrics, energy storage, alternatives to Li-ion batteries, and frequency modulation in communications devices. Self-assembly of high k dielectric nanoparticles is a highly attractive means to produce nanostructured films with improved performance,namely dielectric tunability, low leakage, and low loss,as a function of size, composition, and structure. One of the major challenges is conversion of the nanoparticle building block into a reliable thin film device at conditions consistent with integrated device manufacturing or plastic electronics. Here, the development of BaTiO3 and (Ba,Sr)TiO3 superparaelectric uniform nanocrystal (8,12,nm) films prepared at room temperature by evaporative driven assembly with no annealing step is reported. Thin film inorganic and polymer composite capacitors show dielectric constants in the tunable range of 10,30, dependent on composition, and are confirmed to be superparaelectric. Organic thin film transistor (TFT) devices on flexible substrates demonstrate the readiness of nanoparticle-assembled films as gate dielectrics in device fabrication. [source] Ceramic Membranes: Microstructural Engineering of Hydroxyapatite Membranes to Enhance Proton Conductivity (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 24 2009Mater. The inside cover image showns a side view of a hydroxyapatite membrane with aligned crystal domains synthesized as described by Liu et al. on page 3941. The microstructure of the membrane is engineered to promote proton transport through orientation of the proton conducting paths. These novel structures have significantly higher proton conductivity than traditional hydroxyapatite ceramics and may offer improved performance in intermediate temperature fuel cells. [source] Tailored Mesoporosity Development in Zeolite Crystals by Partial Detemplation and DesilicationADVANCED FUNCTIONAL MATERIALS, Issue 1 2009Javier Pérez-Ramírez Abstract Partial detemplation of zeolites followed by desilication in alkaline medium is demonstrated as a powerful and elegant approach to design hierarchical zeolites with tailored degree of mesoporosity. This achievement, illustrated for large beta crystals, is based on the fact that the template-containing zeolite is virtually inert to Si leaching upon treatment in aqueous NaOH solutions. Partial removal of the structure-directing agent creates regions in the crystal susceptible to mesopore formation by subsequent desilication, while template-containing regions are protected from silicon extraction. Variation of the calcination temperature in the range 230,550,°C determines the amount of template removed and enables control of the extent of mesopore formation in the zeolite (20,230,m2,g,1) upon alkaline treatment. The functionality of the introduced mesoporosity in the hierarchical beta crystals is demonstrated by the improved performance in the catalytic pyrolysis of low-density polyethylene. The partial detemplation,desilication treatment enhances the tuning options of this demetallation method. [source] Microstructural Origin of High Mobility in High-Performance Poly(thieno-thiophene) Thin-Film TransistorsADVANCED MATERIALS, Issue 6 2010Chenchen Wang High-mobility PBTTT thin-film transistors are modeled with a mobility edge model and compared with P3HT. Their improved performance is not due to a low trap density but rather due to high mobility in the crystallites. Characterization of delaminated films with transmission electron microscopy and atomic force microscopy indicates terraces that are composed of nanometer-scale features (see figure). [source] A developmental fMRI study of self-regulatory controlHUMAN BRAIN MAPPING, Issue 11 2006Rachel Marsh Abstract We used functional magnetic resonance imaging (fMRI) to investigate the neural correlates of self-regulatory control across development in healthy individuals performing the Stroop interference task. Proper performance of the task requires the engagement of self-regulatory control to inhibit an automatized response (reading) in favor of another, less automatic response (color naming). Functional MRI scans were acquired from a sample of 70 healthy individuals ranging in age from 7 to 57 years. We measured task-related regional signal changes across the entire cerebrum and conducted correlation analyses to assess the associations of signal activation with age and with behavioral performance. The magnitude of fMRI signal change increased with age in the right inferolateral prefrontal cortex (Brodmann area [BA] 44/45) and right lenticular nucleus. Greater activation of the right inferolateral prefrontal cortex also accompanied better performance. Activity in the right frontostriatal systems increased with age and with better response inhibition, consistent with the known functions of frontostriatal circuits in self-regulatory control. Age-related deactivations in the mesial prefrontal cortex (BA 10), subgenual anterior cingulate cortex (BA 24), and posterior cingulate cortex (BA 31) likely represented the greater engagement of adults in self-monitoring and free associative thought processes during the easier baseline task, consistent with the improved performance on this task in adults compared with children. Although we cannot exclude the possibility that age-related changes in reading ability or in the strategies used to optimize task performance were responsible for our findings, the correlations of brain activation with performance suggest that changes in frontostriatal activity with age underlie the improvement in self-regulatory control that characterizes normal human development. Hum Brain Mapp, 2006. © 2006 Wiley-Liss, Inc. [source] Acute cognitive effects of standardised Ginkgo biloba extract complexed with phosphatidylserineHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 4 2007D. O. Kennedy Abstract Recent data suggest that the complexation of standardised Ginkgo biloba extract (GBE) with soy-derived phospholipids enhances the bio-availablity of GBE's active components. The current study therefore aimed to assess the comparative cognitive and mood effects of a low dose of GBE and products complexing the same extract with either phosphatidylserine or phosphatidylcholine. The study utilised a placebo-controlled, multi-dose, double-blind, balanced-crossover design. Twenty-eight healthy young participants received 120,mg GBE, 120,mg GBE complexed with phosphatidylserine (VirtivaÔ), 120,mg GBE complexed with phosphatidylcholine and a matching placebo, on separate days 7 days apart. Cognitive performance was assessed using the Cognitive Drug Research (CDR) computerised test battery and Serial Subtraction tasks immediately prior to dosing and at 1, 2.5, 4 and 6,h thereafter. The primary outcome measures were the four aspects of cognitive performance, which have previously been derived by factor analysis of CDR subtests. Levels of terpenoids (bilobalide, ginkgolide A and ginkgolide B) were concomitantly assessed in plasma samples taken pre-dose and at 3 and 6.5,h post-dose. In keeping with previous research utilising the same methodology, 120,mg of GBE was not associated with markedly improved performance on the primary outcomes. However, administration of GBE complexed with phosphatidylserine resulted both in improved secondary memory performance and significantly increased speed of memory task performance across all of the post-dose testing sessions. Enhancement following GBE complexed with phosphatidylcholine was restricted to a modest improvement in secondary memory performance which was restricted to one post-dose time point. All three treatments were associated with improved calmness. There were no significant differences in post-dose levels of terpenoids between the Ginkgo containing treatments, although this latter finding may be attributable to methodological factors. Complexation with phosphatidylserine appears to potentiate the cognitive effects associated with a low dose of GBE. Further research is required to identify whether this effect is due to the complexation of the extracts, their mere combination, or the separate psychopharmacological actions of the two extracts. Copyright © 2007 John Wiley & Sons, Ltd. [source] The relationship between the learning organization concept and firms' financial performance: An empirical assessmentHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 1 2002Andrea D. Ellinger The concept of the learning organization has received considerable attention in the scholarly literature because superior learning processes have been heralded as a source of competitive advantage. Organizations that embrace strategies consistent with the learning organization are thought to achieve improved performance. Yet few empirical studies have examined the relationship between the learning organization concept and firms' financial performance. To assess this association, the authors obtained managerial responses to the Watkins and Marsick Dimensions of the Learning Organization Questionnaire (DLOQ©) instrument along with both perceptual and objective measures of firms' financial performance. Results suggest a positive association between the learning organization concept and firms' financial performance. The article discusses implications for research and practice. [source] Time and space: Reframing the training and development agendaHUMAN RESOURCE MANAGEMENT, Issue 1 2003Lloyd Baird In this article, we review how time and space relationships are reframing the training and development agenda. As the speed of business moves faster and boundaries become less relevant, we need ways of expanding and choosing how and when learning and development can take place. We need ways to target development on specific business issues and deliver improved performance in less time with reduced cost. We define a learning options framework to help organize, integrate, synthesize, and better fit training and development methodologies to business realities. Specific knowledge, tools, and examples are provided to show how organizations are identifying and choosing among development options. © 2003 Wiley Periodicals, Inc. [source] Creating Early Success in Financial Accounting: Improving Performance on Adjusting Journal Entries,ACCOUNTING PERSPECTIVES, Issue 2 2010FRED PHILLIPS cognition; écritures comptables; formation; intervention Abstract Adjusting journal entries constitute a necessary component of accrual basis accounting and are critical to the accuracy of financial statements. However, accounting students often struggle to comprehend these accounting entries, which is a concern given that failure to understand early topics in accounting courses has been found to impact course performance and selection of undergraduate major. Perceiving accounting as a language, we utilize psycholinguistic theory to understand how an instructor may improve coherence of students' mental structures of accounting problems. We conduct an experiment to investigate the extent to which a simple instructor intervention, requiring that the initial deferral transaction be recorded, is able to improve student performance on the subsequent deferral adjustments, and whether this improvement is consistent across problem sets that differ in task difficulty. Consistent with our theoretical prediction, we find that this intervention results in improved performance. The beneficial effect of the intervention is found to differ across problem-set task difficulty. Implications for accounting education are discussed. Favoriser dès le départ la réussite en comptabilité générale en améliorant la qualité des écritures de régularisation Résumé Les écritures de régularisation font partie intégrante de la comptabilité d'exercice et sont indispensables à l'exactitude des états financiers. Or, les étudiants en comptabilitééprouvent souvent de la difficultéà comprendre ces écritures comptables, observation préoccupante puisque la méconnaissance de notions élémentaires des cours de comptabilité influe, a-t-on constaté, sur la réussite des cours et le choix d'une majeure au premier cycle. Envisageant la comptabilité comme un langage, les auteurs ont recours à la théorie de la psycholinguistique pour déterminer comment un enseignant peut améliorer la cohérence des structures mentales avec lesquelles les étudiants abordent des problèmes comptables. Ils se livrent à une expérience dans laquelle ils analysent dans quelle mesure la simple intervention de l'enseignant, exigeant la comptabilisation initiale d'une opération de report, peut améliorer la performance de l'étudiant en ce qui a trait aux ajustements de report subséquents, et si cette amélioration demeure constante dans des problématiques où la difficulté de la tâche diffère. Conformément à leur prévision théorique, les auteurs constatent que cette intervention entraîne une amélioration de la performance. Ils observent que l'effet bénéfique de cette intervention diffère selon la difficulté de la tâche associée à la problématique. Enfin, ils analysent les conséquences de ces observations pour la formation comptable. [source] A cross-coupling reference model control algorithmINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 8 2005Y. Xiao Abstract This paper presents an extended cross-coupling generalized predictive control algorithm with reference models for multi-axis coordinated motion systems. It is obtained by minimization of a modified performance index in which the synchronization errors between different motion axes are embedded. Therefore, through adequately adjusting the control parameters the resulting control system may provide an improved performance in terms of tracking and synchronization. An application of the proposed algorithm to an electro-hydraulic process is completed, and the simulation results demonstrating the good performance are also given. Copyright © 2005 John Wiley & Sons, Ltd. [source] Adaptive least mean squares block Volterra filtersINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 4 2001Tarek I. Haweel Abstract Adaptive filtering has found many applications in situations where the underlying signals are changing or unknown. While linear filters are simple from implementation and conceptual points of view, many signals are non-linear in nature. Non-linear filters based on truncated Volterra expansions can effectively model a large number of systems. Unfortunately, the resulting input auto-moment matrix is ill conditioned, which results in a slow convergence rate. This paper proposes a class of block adaptive Volterra filters in which the input sequences are Hadamard transformed to improve the condition number of the input auto-moment matrix and consequently improve the convergence rate. This is achieved by the decorrelation effect produced by the orthogonality of the transform. Since Hadamard transformation employs only ±1's, the additional required computational and implementation burdens are few. The effect of additive white Gaussian noise is introduced. Simulation experiments are given to illustrate the improved performance of the proposed method over the conventional Volterra LMS method. Copyright © 2001 John Wiley & Sons, Ltd. [source] High-resolution images from compressed low-resolution video: Motion estimation and observable pixelsINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2004L. D. Alvarez Abstract In this article, we address the problem of obtaining a high-resolution (HR) image from a compressed low-resolution (LR) video sequence. Motion information plays a critical role in solving this problem, and we determine which pixels in the sequence provide useful information for calculating the high-resolution image. The bit stream of hybrid motion compensated video compression methods includes low-resolution motion-compensated images; we therefore also study which pixels in these images should be used to increase the quality of the reconstructed image. Once the useful (observable) pixels in the low-resolution and motion-compensated sequences have been detected, we modify the acquisition model to only account for these observations. The proposed approach is tested on real compressed video sequences and the improved performance is reported. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 14, 58,66, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.20008 [source] The influence of age on reproductive performance in the Brown ThornbillJOURNAL OF AVIAN BIOLOGY, Issue 1 2001David J. Green I examined age effects on reproduction in the Brown Thornbill Acanthiza pusilla in Canberra, Australia. I found that the reproductive performance of both males and females improved with age, although only age-related improvement in male performance had a significant effect on annual reproductive success. Reproductive success improved with male age as a result of improved performance during two stages of the breeding cycle: first-year males were less likely to fledge young than those aged two or more, while both first and second-year males were less successful at raising fledglings to independence than males of three or more. Male performance appears to improve over three years as they gain experience at provisioning nestlings and caring for fledglings without attracting predators, rather than as a direct result of improved foraging skills. In contrast, reproductive success only improved slightly with female age, although females of two or more years initiated their first clutch earlier in the season than one-year-old females, and tended to be more likely to re-nest if a breeding attempt failed. The poor performance of young females appears unlikely to be related to their foraging ability but may be associated with costs imposed by dispersing to a breeding vacancy earlier in the year. Although the reproductive performance of Brown Thornbills improves considerably with age I found no evidence that performance improved as a result of repeated breeding attempts with the same partner. [source] Design and Analysis of Bioenergy NetworksJOURNAL OF INDUSTRIAL ECOLOGY, Issue 2 2009A Complex Adaptive Systems Approach Summary This article presents a new methodology for designing industrial networks and analyzing them dynamically from the standpoint of sustainable development. The approach uses a combination of optimization and simulation tools. Assuming "top-down" overarching control of the network, we use global dynamic optimization to determine which evolutionary pathways are preferred in terms of economic, social, and environmental performance. Considering the autonomy of network entities and their actions, we apply agent-based simulation to analyze how the network actually evolves. These two perspectives are integrated into a powerful multiscale modeling framework for evaluating the consequences of new policy instruments or different business strategies aimed at stimulating sustainable development as well as identifying optimal leverage points for improved performance of the network in question. The approach is demonstrated for a regional network of interdependent organizations deploying a set of bioenergy technologies within a developing-economy context. [source] Integration of data mining into a nonlinear experimental design approach for improved performanceAICHE JOURNAL, Issue 11 2009Guiying Zhang First page of article [source] Shared thinking: metacognitive modelling in the literacy hourLITERACY, Issue 2 2002Ros Fisher This paper considers evidence from an ESRC funded study of twenty teachers, teaching the literacy hour. In 170 hours of observation only one instance of a teacher modelling her thinking about reading or writing was recorded: and this was unplanned. It is suggested here that, although there should be opportunities for metacognitive modelling within the literacy hour, teachers find it difficult to use these opportunities. Some ideas about the importance of metacognition are reviewed and an example of metacognitive modelling in shared writing is analysed. It is argued that concern for improved performance may cause more attention to be focused on what is to be achieved rather than how. [source] Ionic Polymer-Metal Composite Actuators Employing Radiation-Grafted Fluoropolymers as Ion-Exchange MembranesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 3 2006Man Jae Han Abstract Summary: To develop ionic polymer-metal composites (IPMC) with improved performance, three new ion-exchange membranes were prepared and employed in IPMC construction. The membranes were prepared by radiation-grafting of polystyrene sulfonic acid onto three fluoropolymers; poly(vinylidenefluoride- co -hexafluoropropylene), poly(ethylene- co -tetrafluoroethylene), and poly(tetrafluoroethylene- co -hexafluoropropylene). The bending displacements of the IPMCs constructed with these membranes were at least several times larger than that of Nafion IPMC of similar thickness without straightening-back. The larger displacement was considered to be due to the higher concentration of ionic groups and consequent larger ion-exchange capacity. Actuation of (a) Nafion IPMC and (b) IPMC prepared in this study. [source] Improved signal spoiling in fast radial gradient-echo imaging: Applied to accurate T1 mapping and flip angle correctionMAGNETIC RESONANCE IN MEDICINE, Issue 5 2009Wei Lin Abstract In conventional spoiled gradient echo imaging utilizing quadratic radio frequency (RF) spoiling, nonideal signal intensities are often generated, particularly when repetition time is short and/or excitation flip angle (FA) becomes larger. This translates to significant errors in various quantitative applications based on T1 -weighted image intensities. In this work, a novel spoiling scheme is proposed, based on random gradient moments and RF phases. This scheme results in a non-steady-state condition, but achieves ideal mean signal intensity. In order to suppress artifacts created by the inter-TR signal variations and at the same time attain the ideal signal intensity, radial data acquisition is utilized. The proposed method achieves ideal spoiling for a wide range of T1, T2, TR, and FAs. Phantom and in vivo experiments demonstrate improved performance for T1 mapping and FA correction when compared with conventional RF spoiling methods. Magn Reson Med, 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||