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Key Advantage (key + advantage)
Selected AbstractsROBUST ESTIMATION OF SMALL-AREA MEANS AND QUANTILESAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 2 2010Nikos Tzavidis Summary Small-area estimation techniques have typically relied on plug-in estimation based on models containing random area effects. More recently, regression M-quantiles have been suggested for this purpose, thus avoiding conventional Gaussian assumptions, as well as problems associated with the specification of random effects. However, the plug-in M-quantile estimator for the small-area mean can be shown to be the expected value of this mean with respect to a generally biased estimator of the small-area cumulative distribution function of the characteristic of interest. To correct this problem, we propose a general framework for robust small-area estimation, based on representing a small-area estimator as a functional of a predictor of this small-area cumulative distribution function. Key advantages of this framework are that it naturally leads to integrated estimation of small-area means and quantiles and is not restricted to M-quantile models. We also discuss mean squared error estimation for the resulting estimators, and demonstrate the advantages of our approach through model-based and design-based simulations, with the latter using economic data collected in an Australian farm survey. [source] Adding Depth to Cartoons Using Sparse Depth (In)equalitiesCOMPUTER GRAPHICS FORUM, Issue 2 2010D. Sıkora Abstract This paper presents a novel interactive approach for adding depth information into hand-drawn cartoon images and animations. In comparison to previous depth assignment techniques our solution requires minimal user effort and enables creation of consistent pop-ups in a matter of seconds. Inspired by perceptual studies we formulate a custom tailored optimization framework that tries to mimic the way that a human reconstructs depth information from a single image. Its key advantage is that it completely avoids inputs requiring knowledge of absolute depth and instead uses a set of sparse depth (in)equalities that are much easier to specify. Since these constraints lead to a solution based on quadratic programming that is time consuming to evaluate we propose a simple approximative algorithm yielding similar results with much lower computational overhead. We demonstrate its usefulness in the context of a cartoon animation production pipeline including applications such as enhancement, registration, composition, 3D modelling and stereoscopic display. [source] LazyBrush: Flexible Painting Tool for Hand-drawn CartoonsCOMPUTER GRAPHICS FORUM, Issue 2 2009Daniel Sıkora Abstract In this paper we present LazyBrush, a novel interactive tool for painting hand-made cartoon drawings and animations. Its key advantage is simplicity and flexibility. As opposed to previous custom tailored approaches [SBv05, QWH06] LazyBrush does not rely on style specific features such as homogenous regions or pattern continuity yet still offers comparable or even less manual effort for a broad class of drawing styles. In addition to this, it is not sensitive to imprecise placement of color strokes which makes painting less tedious and brings significant time savings in the context cartoon animation. LazyBrush originally stems from requirements analysis carried out with professional ink-and-paint illustrators who established a list of useful features for an ideal painting tool. We incorporate this list into an optimization framework leading to a variant of Potts energy with several interesting theoretical properties. We show how to minimize it efficiently and demonstrate its usefulness in various practical scenarios including the ink-and-paint production pipeline. [source] Modelling night-time ecosystem respiration by a constrained source optimization methodGLOBAL CHANGE BIOLOGY, Issue 2 2002Chun-Ta Lai Abstract One of the main challenges to quantifying ecosystem carbon budgets is properly quantifying the magnitude of night-time ecosystem respiration. Inverse Lagrangian dispersion analysis provides a promising approach to addressing such a problem when measured mean CO2 concentration profiles and nocturnal velocity statistics are available. An inverse method, termed ,Constrained Source Optimization' or CSO, which couples a localized near-field theory (LNF) of turbulent dispersion to respiratory sources, is developed to estimate seasonal and annual components of ecosystem respiration. A key advantage to the proposed method is that the effects of variable leaf area density on flow statistics are explicitly resolved via higher-order closure principles. In CSO, the source distribution was computed after optimizing key physiological parameters to recover the measured mean concentration profile in a least-square fashion. The proposed method was field-tested using 1 year of 30-min mean CO2 concentration and CO2 flux measurements collected within a 17-year-old (in 1999) even-aged loblolly pine (Pinus taeda L.) stand in central North Carolina. Eddy-covariance flux measurements conditioned on large friction velocity, leaf-level porometry and forest-floor respiration chamber measurements were used to assess the performance of the CSO model. The CSO approach produced reasonable estimates of ecosystem respiration, which permits estimation of ecosystem gross primary production when combined with daytime net ecosystem exchange (NEE) measurements. We employed the CSO approach in modelling annual respiration of above-ground plant components (c. 214 g C m,2 year,1) and forest floor (c. 989 g C m,2 year,1) for estimating gross primary production (c. 1800 g C m,2 year,1) with a NEE of c. 605 g C m,2 year,1 for this pine forest ecosystem. We conclude that the CSO approach can utilise routine CO2 concentration profile measurements to corroborate forest carbon balance estimates from eddy-covariance NEE and chamber-based component flux measurements. [source] Adaptive robust force control for vehicle active suspensionsINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 2 2004Supavut Chantranuwathana Abstract In this paper, the modular adaptive robust control (MARC) technique is applied to design the force loop controller of an electro-hydraulic active suspension system. A key advantage of this modular design approach lies in the fact that the adaptation algorithm can be designed for explicit estimation convergence. The effect of parameter adaptation on force tracking performance can be compensated and thus it is possible to guaranteed certain control performance. Experimental results from a quarter-car active suspension test rig show that when realistic external disturbances and measurement noises exist, the modular design achieves a better estimate than the non-modular ARC design. The improved estimation was found to result in control signals with slightly lower magnitude while maintaining similar tracking performance. Copyright © 2004 John Wiley & Sons, Ltd. [source] Monitoring Delamination Progression in Thermal Barrier Coatings by Mid-Infrared Reflectance ImagingINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 2 2006Jeffrey I. Eldridge Mid-infrared (MIR) reflectance imaging is shown to be a reliable diagnostic tool for monitoring delamination progression in thermal barrier coatings (TBCs). MIR reflectance imaging utilizes the maximum transparency of TBCs in the 3,6 ,m wavelength region to probe below-surface delamination crack propagation that is typically hidden from visible wavelength inspection. The image contrast that identifies delamination progression arises from the increased reflectance produced by a large component of total internal reflection at the TBC/buried-crack interface. Imaging was performed at a wavelength of 4 ,m to take advantage of the relatively high transmittance of plasma-sprayed 8 wt% yttria-stabilized zirconia (8YSZ) TBCs along with a desirable relative insensitivity to potentially interfering absorptions by atmospheric constituents at that wavelength. A key advantage of MIR reflectance imaging over competing techniques is that it is sensitive to delamination progression even at very early stages before delamination cracks start linking together; therefore, TBC health assessment can be achieved throughout the life of the TBC well before TBC failure is imminent. Examples are presented to demonstrate monitoring delamination progression by MIR reflectance imaging in 8YSZ TBC-coated specimens subjected to furnace cycling to 1163°C. The experimental results were in good agreement with reflectance values predicted by a four-flux Kulbelka,Munk approximation applied to the extreme cases of a completely adherent and a completely detached TBC. Practical considerations, including potential interfering effects from surface contamination, sintering, and erosion are discussed. [source] Template-directed synthesis of hybrid nanowires and nanorodsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 10 2010Jiayin Yuan Abstract Recently, one-dimensional (1D) nanostructures, such as wires, rods, tubes, etc., have attracted considerable attention due to their unique shape- and size-dependant properties and many potential applications. Template-directed synthesis is a powerful and widely used method to prepare 1D objects. As robust unimolecular template, cylindrical polymer brushes have been exploited for the fabrication of various hybrid nanowires and nanorods, for instance, ,-Fe2O3, CdS, CdSe, TiO2, silica, Au, Te, etc. As a key advantage of this polymeric templating, the obtained 1D hybrid nanostructures are colloidally stable in solution, facilitating their further solution processing. Cryo-TEM image of organo-silica hybrid nanowires in aqueous solution (the inset shows a cartoon of the structure). [source] Imaging mass spectrometry: Towards clinical diagnosticsPROTEOMICS - CLINICAL APPLICATIONS, Issue 10-11 2008Erin H. Seeley Abstract Imaging MS (IMS) has emerged as a powerful tool for biomarker discovery. A key advantage of this technique is its ability to probe the proteome directly from a tissue section with preservation of the spatial relationships of the sample and minimal sample preparation. This allows for direct correlation of protein expression with histology. Here, we present the latest developments in imaging MS and their relevance to clinical mass spectral analysis. IMS allows for high throughput analysis of tissue samples and is fully compatible with biostatistical analysis without prior knowledge of protein expression. Several studies are presented of applications in which direct tissue mass spectral analysis has provided insight into clinical questions not readily available by other means. Examples include the determination of lymph node status from investigation of primary breast tumors, prediction of response of breast tumors to chemotherapy, classification and prediction of progression of lung lesions, and exploration of ,molecular' margins in invasive disease. [source] Policy networks and the GM crops issue: assessing the utility of a dialectical model of policy networksPUBLIC ADMINISTRATION, Issue 2 2003David Toke A dialectical model of policy networks is deployed to analyse policy change in the area of GM crops in the UK. The model uses an analysis of the interaction between agents and structure, network and context and network and outcomes to understand and explain how policy change has occurred. A key advantage of the model is that it increases understanding of network transformation, explanation of which has been an alleged weakness of the policy network approach. However, this case study does throw up some weaknesses with the model, including the tendency of the model to emphasize the role of ,insider' agents and downplay the role of ,outsiders' in the policy process. [source] A comparative analysis of constitutive and cell-specific promoters in the adult mouse hippocampus using lentivirus vector-mediated gene transferTHE JOURNAL OF GENE MEDICINE, Issue 11 2008Hitoshi Kuroda Abstract Background Viral vectors provide powerful tools for transgene delivery to the mammalian brain to assess the effects of therapeutic proteins, antisense RNAs or small interfering RNAs. A key advantage of such approaches is that specific brain regions implicated in a particular disease can be independently targeted. Methods To optimize transgene expression in sub-regions of the mouse hippocampus and with a view towards devising gene therapy strategies for Alzheimer's disease, we designed lentivirus-based reporter vectors bearing various promoters, including constitutive and cell-specific promoters. Furthermore, we devised methods allowing a side-by-side comparison of transgene expression levels in neural cells both in vitro and in vivo. Results Following stereotaxic injection into the adult mouse hippocampus, titer-adjusted lentiviral vectors bearing constitutive promoters resulted in robust and sub-region-specific transgene expression. Our results show that the human CMV-IE promoter resulted in efficient transgene expression in the entire hippocampus whereas transgene expression mediated by the hybrid hEF1,/HTLV promoter was limited mainly in the dentate gyrus and the CA2/3 region. Finally, the neuron-specific human synapsin I promoter was particularly effective in the dentate gyrus. Conclusions These findings indicate that subregion-specific transgene expression in the hippocampus can be achieved following lentivirus vector-mediated gene transfer. Copyright © 2008 John Wiley & Sons, Ltd. [source] Self-regulating hyperthermia induced using thermosensitive ferromagnetic material with a low Curie temperatureCANCER SCIENCE, Issue 4 2008Hajime Saito Hyperthermia has been used for many years to treat a variety of malignant tumors. The Curie temperature (Tc) is a transition point at which magnetic materials lose their magnetic properties, causing a cessation of current and thus heat production. The Tc enables automatic temperature control throughout a tumor as a result of the self-regulating nature of the thermosensitive material. We have developed a method of magnetically-induced hyperthermia using thermosensitive ferromagnetic particles (FMPs) with low Tc (43°C), enough to mediate automatic temperature control. B16 melanoma cells were subcutaneously injected into the backs of C57BL/6 mice, after which tumors were allowed to grow to 5 mm in diameter. FMPs were then injected into the tumors, and the mice were divided into three groups: group I (no hyperthermia, control); group II (one hyperthermia treatment); and group III (hyperthermia twice a week for 4 weeks). When exposed to a magnetic field, the FMPs showed a sharp rise in heat production, reaching the Tc in tissue within 7 min, after which the tissue temperature stabilized at approximately the Tc. In groups I and II, all mice died within 30,45 days. In group III, however, 6 of 10 mice remained alive 120 days after beginning treatment. Our findings suggest that repeated treatment with magnetically-induced self-regulating hyperthermia, mediated by FMPs with a low Tc, is an effective means of suppressing melanoma growth. A key advantage of this hyperthermia system is that it is minimally invasive, requiring only a single injection for repeated treatments with automatic temperature control. (Cancer Sci 2008; 99: 805,809) [source] Shear band evolution and accumulated microstructural development in Cosserat mediaINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 10 2004A. Tordesillas Abstract This paper prepares the ground for the continuum analysis of shear band evolution using a Cosserat/micropolar constitutive equation derived from micromechanical considerations. The nature of the constitutive response offers two key advantages over other existing models. Firstly, its non-local character obviates the mathematical difficulties of traditional analyses, and facilitates an investigation of the shear band evolution (i.e. the regime beyond the onset of localization). Secondly, the constitutive model parameters are physical properties of particles and their interactions (e.g. particle stiffness coefficients, coefficients of inter-particle rolling friction and sliding friction), as opposed to poorly understood fitting parameters. In this regard, the model is based on the same material properties used as model inputs to a discrete element (DEM) analysis, therefore, the micromechanics approach provides the vehicle for incorporating results not only from physical experiments but also from DEM simulations. Although the capabilities of such constitutive models are still limited, much can be discerned from their general rate form. In this paper, an attempt is made to distinguish between those aspects of the continuum theory of localization that are independent of the constitutive model, and those that require significant advances in the understanding of micromechanics. Copyright © 2004 John Wiley & Sons, Ltd. [source] Bismuth-Doped Ceria, Ce0.90Bi0.10O2: A Selective and Stable Catalyst for Clean Hydrogen CombustionADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2009Jurriaan Beckers Abstract Bismuth-doped cerias are successfully applied as solid "oxygen reservoirs" in the oxidative dehydrogenation of propane. The lattice oxygen of the ceria is used to selectively combust hydrogen from the dehydrogenation mixture at 550,°C. This process has three key advantages: it shifts the dehydrogenation equilibrium to the desired products side, generates heat, aiding the endothermic dehydrogenation, and simplifies product separation (water vs. hydrogen). Furthermore, the process is safer, since it uses the catalyst's lattice oxygen instead of gaseous oxygen. We show here that bismuth-doped cerias are highly active and stable towards hydrogen combustion, and explore four different approaches for optimising their application in the oxidative dehydrogenation of propane: first, the addition of extra hydrogen which lowers hydrocarbon conversion by suppressing both combustion and coking; second, the addition of tin which completely inhibits coking; third, the addition of platinum which increases selectivity, but at the expense of lower activity. The best results are obtained through tuning the reaction temperature. At 400,°C, high activity and selectivity were obtained for the bismuth-doped ceria Ce0.90Bi0.10O2. Here, 90% of the hydrogen feed is converted at 98% selectivity. This optimal reaction temperature can be rationalised from the hydrogen and propene temperature-programmed reduction (TPR) profiles: 400,°C lies above the reduction maximum of hydrogen, yet below that of propene. That is, this temperature is sufficiently high to facilitate rapid hydrogen combustion, but low enough to prevent hydrocarbon conversion. [source] TRANSFERABLE STOCK OPTIONS (TSOS) AND THE COMING REVOLUTION IN EQUITY-BASED PAYJOURNAL OF APPLIED CORPORATE FINANCE, Issue 1 2004Brian J. Hall The dominant form of equity pay in the U.S. will change dramatically when accounting rules are changed (most likely in 2005) to require companies to charge the cost of their stock option plans on their income statements. Many companies are already switching from stock options to other forms of equity pay, especially restricted stock. The most notable switcher was Microsoft, the world's largest user of stock option pay. In July 2003, partnering with J.P. Morgan, Microsoft created a onetime transferable stock option (TSO) program that allowed holders of underwater Microsoft options to sell their options to J.P. Morgan in return for restricted shares. But the most important consequence of this transaction may not be a widespread shift by corporate America to restricted shares, but rather the creation of a more costeffective kind of stock option. By clearing the potentially messy hurdles involving taxes, accounting, SEC rules, and "transaction mechanics," Microsoft has opened the door for TSOs to be considered as an ongoing equitypay instrument, perhaps replacing standard stock options (which are not transferable). TSOs share the key advantages of restricted stock in terms of providing robust retention and ownership incentives and higher valuecost efficiency, while maintaining the key "leverage" advantage of options. In so doing, they create significant upside (and downside) while largely avoiding the "pay for pulse" problem of restricted stock. They also introduce the discipline of competitive pricing by third-party bidders. The bid prices of investment banks create nearly all of the information required for accurate estimates of option cost, which should foster greater board accountability and improved corporate governance. [source] Dynamic Metabolic Modeling for a MAB BioprocessBIOTECHNOLOGY PROGRESS, Issue 1 2007Jianying Gao Production of monoclonal antibodies (MAb) for diagnostic or therapeutic applications has become an important task in the pharmaceutical industry. The efficiency of high-density reactor systems can be potentially increased by model-based design and control strategies. Therefore, a reliable kinetic model for cell metabolism is required. A systematic procedure based on metabolic modeling is used to model nutrient uptake and key product formation in a MAb bioprocess during both the growth and post-growth phases. The approach combines the key advantages of stoichiometric and kinetic models into a complete metabolic network while integrating the regulation and control of cellular activity. This modeling procedure can be easily applied to any cell line during both the cell growth and post-growth phases. Quadratic programming (QP) has been identified as a suitable method to solve the underdetermined constrained problem related to model parameter identification. The approach is illustrated for the case of murine hybridoma cells cultivated in stirred spinners. [source] | ||||||||||||||||