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Generalization
Kinds of Generalization Terms modified by Generalization Selected AbstractsCONCEPTUAL CLUSTERING AND CASE GENERALIZATION OF TWO-DIMENSIONAL FORMSCOMPUTATIONAL INTELLIGENCE, Issue 3-4 2006Silke Jänichen Case-based object recognition requires a general case of the object that should be detected. Real-world applications such as the recognition of biological objects in images cannot be solved by one general case. A case base is necessary to handle the great natural variations in the appearance of these objects. In this paper, we will present how to learn a hierarchical case base of general cases. We present our conceptual clustering algorithm to learn groups of similar cases from a set of acquired structural cases of fungal spores. Due to its concept description, it explicitly supplies for each cluster a generalized case and a measure for the degree of its generalization. The resulting hierarchical case base is used for applications in the field of case-based object recognition. We present results based on our application for health monitoring of biologically hazardous material. [source] Intrinsic Ictal Dynamics at the Seizure Focus: Effects of Secondary Generalization Revealed by Complexity MeasuresEPILEPSIA, Issue 2 2007Christophe C. Jouny Summary:,Purpose: Partial seizures (PSs) may be self-limited regional events or propagate further and secondarily generalize. The mechanisms and dynamics of secondarily generalized tonic,clonic seizures (GTCSs) are not well understood. Methods with which to assess the dynamic of those events are also limited. Methods: Seizures were analyzed from patients with intractable partial seizures undergoing monitoring with intracranial electrodes. Inclusion in this study required patients to have at least one PS and one GTCS. From >120 patients, seven patients fulfilled these criteria, three with mesial temporal (MTLE) onset seizures and four with neocortical lesional (NCLE) onset seizures. In total, 50 seizures were analyzed by using the matching pursuit (MP) method and the Gabor atom density (GAD), a measure of signal complexity derived from the MP method. Results: The GAD complexity pattern at the seizure focus for the initial ictal period is remarkably consistent in a given patient, regardless of whether secondary generalization occurs. Secondary generalization produces greater modification of seizure activity at the focus in patients with NCLE than in patients with MTLE. In seizures from four patients with NCLE, secondary generalization resulted in an average increase of 115% in complexity at the focus compared to PSs. Conclusions: GAD shows that seizure dynamics of PSs are often very stereotyped from seizure to seizure in a given patient, particularly during early ictal evolution. Secondary generalization is more likely to produce changes in the duration and dynamics at the seizure focus in NCLE patients compared with MTLE patients. These observations suggest distinct mechanisms (e.g., feedback) that are operational during secondary generalization. [source] Generalization of positive attitude as a function of subgroup and superordinate group identifications in intergroup contactEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2003Roberto González The role of category salience in mediating the effects of intergroup contact was examined. One theoretical model proposes that some psychological salience of subgroup categories is necessary to facilitate the generalization of attitude change beyond the immediate contact situation. Another argues that a re-categorization of the subgroups into a new superordinate category is more beneficial, whilst a third suggests that de-categorizing the situation entirely is optimal. An alternative view, which combines the first two models, proposes a Dual Identity strategy (simultaneous high superordinate and high subgroup categorization) as an important mediator of the relationship between contact variables and intergroup attitudes. In the study, participants (N,=,114) undertook a cooperative intergroup task under four conditions of category salience: ,subgroup', ,superordinate', ,superordinate and subgroup', and ,no group salience'. Evaluative ratings and symbolic reward allocations both for the groups encountered (contact) and those outside the situation (generalization) provided measures of intergroup bias. Bias within the contact situation was mainly eliminated in all conditions. However, on the more generalized bias measures, only the ,superordinate' and ,superordinate and subgroup' (Dual Identity strategy) conditions maintained this low level; in the other two conditions intergroup bias resurfaced. A combination of the first two models is proposed. Copyright © 2002 John Wiley & Sons, Ltd. [source] Generalization of Schrödinger invariance.FORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 5-7 2009Applications to Bose-Einstein condensation Abstract The symmetries of non-linear Schrödinger equations with power-law non-linearities are investigated. It is shown that Galilei invariance can be extended to Schrödinger invariance if the coupling constant(s) in non-linearity is treated as dimensionful quantity. This is used to find a new non-stationary solutions from given stationary ones. [source] Productivity,quality,costs,safety: A sustained approach to competitive advantage,a systematic review of the national safety council's case studies in safety and productivityHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 2 2008Tushyati Maudgalya The marked improvement in workplace safety levels in the past few decades has resulted in companies experiencing fewer safety accidents than before, thus making it less effective to argue that money spent on workplace safety and on injury prevention will yield much bottom-line benefit. To make a compelling business case for workplace safety investment, one must link safety objectives to other business objectives. The objective of this study is to determine whether workplace safety as a business objective adds value to the business bottom line. This research reviews published case studies to determine if there is a relationship between safety initiatives and increased productivity, quality, and cost efficiencies. Eighteen case studies (17 published by the National Safety Council) were analyzed using the Workplace Safety Intervention Appraisal Instrument. The appraisal scores ranged from 0.55 to 1.27, with an average of 0.91. The case studies were relatively strong in the Evidence Reporting and Data Analysis categories, as compared to the Subject Selection, Observation Quality, and Generalization to Other Populations categories. Following workplace safety initiatives, the studies revealed an average increase of 66% (2%,104%) in productivity, 44% (4%,73%) in quality, 82% (52%,100%) in safety records, and 71% (38%,100%) in cost benefits. In a few reported cases, it took only 8 months to obtain a payback in terms of monetary investment in the safety initiative. Although the studies did display a correlation between safety, productivity, and quality, there is insufficient evidence to categorically state that the improvements in productivity, quality, and cost efficiency were brought about by the introduction of an organization-wide safety culture. Notwithstanding, there is demonstrable evidence to indicate that safety as a business objective can assist an organization in achieving the long-term benefit of operational sustainability, that is, achieve a long-term competitive advantage by balancing business costs against social costs. Further research is required to conclusively prove the exact (possibly quantifiable) impact of safety investment on increased productivity, quality, and cost efficiency. © 2008 Wiley Periodicals, Inc. [source] The Effect of Learning Experiences and Context on Infant Imitation and GeneralizationINFANCY, Issue 6 2008Emily J. H. Jones Over the first years of life, infants gradually develop the ability to retrieve their memories across cue and contextual changes. Whereas maturational factors drive some of these developments in memory ability, experiences occurring within the learning event may also impact infants' ability to retrieve memories in new situations. In 2 experiments we examined whether it was possible to facilitate 12-month-old infants' generalization of learning in the deferred imitation paradigm by varying experiences before or during the demonstration session, or during the retention interval. In Experiment 1, altering the length, timing, or variability of training had no impact on generalization; infants showed a low, but consistent level of memory retrieval. In Experiment 2, infants who experienced a unique context for encoding and retrieval exhibited generalization; infants who experienced the context prior to the demonstration session, or during the retention interval, did not. Specificity is a robust feature of infant memory and is not substantially altered by encoding experiences in an observational learning paradigm. Previous history with a learning environment can, however, impact the flexibility of memory retrieval. [source] Generalization of robustness test procedure for error estimators.INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2005Part I: formulation for patches near kinked boundaries Abstract In this part of paper we shall extend the formulation proposed by Babu,ka and co-workers for robustness patch test, for quality assessment of error estimators, to more general cases of patch locations especially in three-dimensional problems. This is performed first by finding an asymptotic finite element solution at interior parts of a problem with assumed smooth exact solution and then adding a correction part to obtain the solution near a kinked boundary irrespective of other boundary conditions at far ends of the domain. It has been shown that the solution corresponding to the correction part may be obtained in a spectral form by assuming a suitable proportionality relation between the nodal values of a mesh with repeatable pattern of macro-patches. Having found the asymptotic finite element solution, the performance of error estimators may be examined. Although in this paper we focus on the asymptotic behaviour of error estimators, the method described in this part may be used to obtain finite element solution for two/three-dimensional unbounded heat/elasticity problems with homogeneous differential equations. Some numerical results are presented to show the validity and performance of the proposed method. Copyright © 2005 John Wiley & Sons, Ltd. [source] Generalization of robustness test procedure for error estimators.INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2005Part II: test results for error estimators using SPR Abstract In this part of the paper we shall use the formulation given in the first part to assess the quality of recovery-based error estimators using two recovery methods, i.e. superconvergent patch recovery (SPR) and recovery by equilibrium in patches (REP). The recovery methods have been shown to be asymptotically robust and superconvergent when applied to two-dimensional problems. In this study we shall examine the behaviour of the recovery methods on several three-dimensional mesh patterns for patches located either inside or at boundaries. This is performed by first finding an asymptotic finite element solution, irrespective of boundary conditions at far ends of the domain, and then applying the recovery methods. The test procedure near kinked boundaries is explained in a step-by-step manner. The results are given in a series of tables and figures for various cases of three-dimensional mesh patterns. It has been experienced that the full superconvergent property is generally lost due to presence of boundary layer solution and the definition of the recoveries near boundaries though the results of the robustness test is still within an acceptable range. Copyright © 2005 John Wiley & Sons, Ltd. [source] Angle differential-QAM scheme for resolving phase ambiguity in continuous transmission systemINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 6 2008Jeng-Kuang Hwang Abstract An angle differential quadrature amplitude modulation (ADQAM) scheme is proposed to solve phase ambiguity problem in non-data-aided continuous transmission system with square QAM constellation. Starting from the 16-ADQAM case, we derive differential encoding and decoding schemes in terms of two differential angles and use a solar system analogy for explanation. The 16-ADQAM system incurs only about 0.5-dB performance degradation compared with the coherent 16-QAM system under AWGN channel. Generalization of flat fading channel and higher-level ADQAM is straightforward. Copyright © 2007 John Wiley & Sons, Ltd. [source] Generalization of belief and plausibility functions to fuzzy sets based on the sugeno integralINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 11 2007Chao-Ming Hwang Uncertainty has been treated in science for several decades. It always exists in real systems. Probability has been traditionally used in modeling uncertainty. Belief and plausibility functions based on the Dempster,Shafer theory (DST) become another method of measuring uncertainty, as they have been widely studied and applied in diverse areas. Conversely, a fuzzy set has been successfully used as the idea of partial memberships of multiple classes for the presentation of unsharp boundaries. It is well used as the representation of human knowledge in complex systems. Nowadays, there exist several generalizations of belief and plausibility functions to fuzzy sets in the literature. In this article, we propose a new generalization of belief and plausibility functions to fuzzy sets based on the Sugeno integral. We then make comparisons of the proposed generalization with some existing methods. The results show the effectiveness of the proposed generalization, especially for being able to catch more information about the change of fuzzy focal elements. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 1215,1228, 2007. [source] Generalization of cluster treatment of characteristic roots for robust stability of multiple time-delayed systemsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 14 2008Rifat Sipahi Abstract A new perspective is presented for studying the stability robustness of nth order systems with p rationally independent delays. It deploys a holographic mapping procedure over the delay space into a new coordinate system in order to achieve the objective. This mapping collapses the entire set of potential stability switching points on a manageably small number of hypersurfaces, which are explicitly defined in the new domain. This property considerably alleviates the problem, which is otherwise infinite dimensional, and therefore notoriously complex to handle. We further declare some unrecognized features of these switching hypersurfaces, that they are (a) encapsulated within a higher-dimensional cube with edges of length 2,, which we name the ,building block', and (b) the ,offspring' of this building block, which represent the secondary stability switchings, appear within the adjacent and identical building blocks (cubes) stacked up next to each other. The final outlook is an exclusive representation of stability for this general class of systems at any arbitrary point in the delay space. Two example case studies are also provided, which are not possible to analyze using any other methodology known to the authors. Copyright © 2007 John Wiley & Sons, Ltd. [source] Generalization of the Nyquist robust stability margin and its application to systems with real affine parametric uncertaintiesINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 15 2001Charles T. Baab The critical direction theory for analysing the robust stability of uncertain feedback systems is generalized to include the case of non-convex critical value sets, hence making the approach applicable for a much larger class of relevant systems. A redefinition of the critical perturbation radius is introduced, leading to the formulation of a Nyquist robust stability measure that preserves all the properties of the previous theory. The generalized theory is applied to the case of rational systems with an affine uncertainty structure where the uncertain parameters belong to a real rectangular polytope. Necessary and sufficient conditions for robust stability are developed in terms of the feasibility of a tractable linear-equality problem subject to a set of linear inequalities, leading ultimately to a computable Nyquist robust stability margin. A systematic and numerically tractable algorithm is proposed for computing the critical perturbation radius needed for the calculation of the stability margin, and the approach is illustrated via examples. Copyright © 2001 John Wiley & Sons, Ltd. [source] Impact of Assessments of Validity Generalization and Situational Specificity on the Science and Practice of Personnel SelectionINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 4 2000Kevin R. Murphy The application of meta-analysis, in particular validity generalization (VG) analysis, to the cumulative literature on the validity of selection tests has fundamentally changed the science and practice of personnel selection. VG analyses suggest that the validities of standardized tests and other structured assessments are both higher and more consistent across jobs and organizations than was previously believed. As a result, selection researchers and practitioners can draw on the research literature to make reasonably accurate forecasts about the validity and usefulness of different tests in particular applications. Distinctions between tests of validity generalization and tests of situational specificity are described, and difficulties in demonstrating that validity is constant across the different settings where tests are used are outlined. [source] Empathic Experience and Attitudes Toward Stigmatized Groups: Evidence for Attitude GeneralizationJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 7 2010Mark Tarrant Two studies investigated the extent to which empathizing with a single member of a stigmatized group can yield positive attitudes toward other stigmatized groups. Participants read a scenario in which a member of a socially stigmatized group described the experiences of group membership. Participants then reported their attitudes toward the target group and a second group. Both studies revealed a generalization effect such that experiencing empathy for the target was associated with more positive attitudes, both toward the target group and the second group. Study 2 demonstrated that this generalization effect is confined to those groups located within the same superordinate category. Implications of these findings for attempts to structure people's orientation to stigmatized groups are discussed. [source] Generalization of multivariate optical computations as a method for improving the speed and precision of spectroscopic analysesJOURNAL OF CHEMOMETRICS, Issue 6 2008Marc K. Boysworth Abstract Multivariate optical computations (MOCs) offer improved analytical precision and increased speed of analysis via synchronous data collection and numerical computation with scanning spectroscopic systems. The improved precision originates in the redistribution of integration time from spurious channels to informative channels in an optimal manner for increasing the signal-to-noise ratio with multivariate analysis under the constraint of constant total analysis time. In this work, MOCs perform the multiplication and addition steps of spectral processing by adjusting the integration parameters of the optical detector or adjusting the scanning profile of the tunable optical filter. Improvement in the precision of analysis is achieved via the implicit optimization of the analytically useful signal-to-noise ratio. The speed improvements are realized through simpler data post-processing, which reduces the computation time required after data collection. Alternatively, the analysis time may be significantly truncated while still seeing an improvement in the precision of analysis, relative to competing methods. Surface plasmon resonance (SPR) spectroscopic sensors and visible reflectance spectroscopic imaging were used as test beds for assessing the performance of MOCs. MOCs were shown to reduce the standard deviation of prediction by 15% compared to digital data collection and analysis with the SPR and up to 45% for the imaging applications. Similarly, a 30% decrease in the total analysis time was realized while still seeing precision improvements. Copyright © 2008 John Wiley & Sons, Ltd. [source] Generalization of rank reduction problems with Wedderburn's formulaJOURNAL OF CHEMOMETRICS, Issue 11 2003Joan Ferré Abstract In first- and second-order calibration methods based on spectroscopic data, the calculation of the space spanned by the spectra of the interferences has been an important research subject for, among many other applications, calculating the net analyte signal and obtaining figures of merit. Recently, many different calculation methods have been introduced. We show that the calculation of this space can be interpreted from a unified point of view, namely from the rank-one downdating Wedderburn formula. This formula enables one to better understand the properties of the calculation methods currently available. A number of recently introduced signal-preprocessing methods also fit into the proposed framework. Copyright © 2004 John Wiley & Sons, Ltd. [source] Facilitating police,minority youth attitude change: The effects of cooperation within a competitive context and exposure to typical exemplarsJOURNAL OF COMMUNITY PSYCHOLOGY, Issue 2 2002Dana Rabois Previous community programs have been unsuccessful in changing youths' attitudes toward police, and have thus far not addressed police attitudes toward youth. In this pilot study, police (n = 26) competed together with minority youths (n = 51) on heterogeneous basketball teams. Pre- and postintervention attitudes toward youths/officers and posttest attitudes toward team members were examined. Police reported positive ratings of out-group team members, and demonstrated a positive shift in attitude toward minority youth in general. Generalization of positive attitude was more likely when officers perceived their team members as typical exemplars of minority youth. Minority youths did not show a significant improvement in attitude toward police but reported favorable attitudes toward team members. Results suggest that a short-term competitive tournament exposing individuals to typical exemplars may be effective for addressing hostile police attitudes toward minority youths. A controlled study is recommended to replicate and expand on our findings. © 2002 John Wiley & Sons, Inc. [source] Generalization and numerical investigation of QMOMAICHE JOURNAL, Issue 1 2007R. Grosch Abstract A generalized framework is developed for the quadrature method of moments (QMOM), which is a solution method for population balance models. It further evaluates the applicability of this method to industrial suspension crystallization processes. The framework is based on the concepts of generalized moments and coordinate transformations, which have been used already in earlier solution approaches. It is shown how existing approaches to QMOM are derived from the suggested unified framework. Thus, similarities and differences between the various QMOM methods are uncovered. Further, potential error sources involved in the different approaches to QMOM are discussed and assessed by means of a series of test cases. The test cases are selected to be challenging. The error in the QMOM solution is evaluated by comparison to an adaptive, error controlled solution of the population balance. The behavior of a range of different QMOM formulations is analyzed by means of numerical quadrature, dynamic simulation, as well as numerical continuation and bifurcation analysis. As a result of this detailed analysis, some general limitations of the method are detected and guidelines for its application are developed. This article is limited to lumped population balance models with one internal coordinate. © 2006 American Institute of Chemical Engineers AIChE J, 2007 [source] Dynamic Voluntary Provision of Public Goods: A GeneralizationJOURNAL OF PUBLIC ECONOMIC THEORY, Issue 1 2009KENJI FUJIWARA In this note we examine if the proposition offered by Fershtman and Nitzan (1991) and Wirl (1996) in the context of a dynamic voluntary provision model with a linear production function can be generalized to a more general CES formulation. By comparing the steady-state stocks of a public good in open-loop and feedback Nash equilibria with that under the cooperative solution, we demonstrate that their ranking among the steady-state stocks is indeed preserved under the CES framework. [source] Zolpidem Generalization and Antagonism in Male and Female Cynomolgus Monkeys Trained to Discriminate 1.0 or 2.0 g,/,kg EthanolALCOHOLISM, Issue 7 2008Christa M. Helms Background:, The subtypes of , -aminobutyric acid (GABA)A receptors mediating the discriminative stimulus effects of ethanol in nonhuman primates are not completely identified. The GABAA receptor positive modulator zolpidem has high, intermediate, and low activity at receptors containing ,1, ,2/3, and ,5 subunits, respectively, and partially generalizes from ethanol in several species. The partial inverse agonist Ro15-4513 has the greatest affinity for ,4/6 -containing receptors, higher affinity for ,5 - and lower, but equal, affinity for ,1 - and ,2/3 -, containing GABAA receptors, and antagonizes the discriminative stimulus effects of ethanol. Methods:, This study assessed Ro15-4513 antagonism of the generalization of zolpidem from ethanol in male (n = 9) and female (n = 8) cynomolgus monkeys (Macaca fascicularis) trained to discriminate 1.0 g/kg (n = 10) or 2.0 g/kg (n = 7) ethanol (i.g.) from water with a 30-minute pretreatment interval. Results:, Zolpidem (0.017 to 5.6 mg/kg, i.m.) completely generalized from ethanol (,80% of total session responses on the ethanol-appropriate lever) for 6/7 monkeys trained to discriminate 2.0 g/kg and 4/10 monkeys trained to discriminate 1.0 g/kg ethanol. Zolpidem partially generalized from 1.0 or 2.0 g/kg ethanol in 6/7 remaining monkeys. Ro15-4513 (0.003 to 0.30 mg/kg, i.m., 5-minute pretreatment) shifted the zolpidem dose,response curve to the right in all monkeys showing generalization. Analysis of apparent pKB from antagonism tests suggested that the discriminative stimulus effects of ethanol common with zolpidem are mediated by low-affinity Ro15-4513 binding sites. Main effects of sex and training dose indicated greater potency of Ro15-4513 in males and in monkeys trained to discriminate 1.0 g/kg ethanol. Conclusions:, Ethanol and zolpidem share similar discriminative stimulus effects most likely through GABAA receptors that contain ,1 subunits, however, antagonism by Ro15-4513 of zolpidem generalization from the lower training dose of ethanol (1.0 g/kg) may involve additional zolpidem-sensitive GABAA receptor subtypes (e.g., ,2/3 and ,5). [source] Verification of a distortion in the microstructure of GaN detected by EXAFS using ab initio density functional theory calculationsJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2001Nicholas Dimakis X-ray absorption fine structure (XAFS) measurements on a series of epitaxially grown GaN samples have shown a distortion in the microstructure of GaN. More specifically the central N atom is 4-fold coordinated but the four Ga atoms are not equidistant. It has been shown that 2.9 to 3.5 of them (depending on the growth conditions) are found in the expected from XRD distance of 1.94 Ĺ and the remaining are at a distance longer by approximately 15%. Second derivative calculation of the conformation energy using the Density Functional Theory (DFT) is used to investigate if the symmetric GaN cluster as given by XRD is the most energetically favorable configuration and if not which distorted structure corresponds to the most energetically favorable one. A very good agreement between DFT results and experimental XAFS spectra has been found. Generalization this technique to other dislocated clusters is also discussed. [source] Generalization Across Segments in Second Language Consonant IdentificationLANGUAGE LEARNING, Issue 1 2009Kenneth J. De Jong This article examines the extent of differences between second language (L2) learners in their abilities to identify L2 consonants and provides evidence for linguistic generalization from one consonant to other consonants. It distinguishes among different sorts of models of the relationship between segments: (a) segmentally specific models in which each segment is treated separately and (b) generalized featural models in which segments that share features are treated as a group. It also examines (c) ordered models in which one segment might rely on another previously existing one. The article presents the results of an experiment with 40 Korean learners of English identifying English obstruents in different prosodic locations, and it examines the pattern of variation in perceptual accuracy across the listeners. Results indicate that manner perception varies from person to person as a unit, regardless of the segment, suggesting a single generalized featural skill. Voicing identification, however, does not vary as a unit across the different prosodic positions, suggesting different skills that are applicable to different prosodic positions and are acquired separately. There is also evidence for an implicational relationship between pairs of segments that differ in markedness, providing some evidence for an ordered model; however, such patterns are not pervasive across different contrasts. [source] Robust estimation of spatially variable noise fieldsMAGNETIC RESONANCE IN MEDICINE, Issue 2 2009Bennett A. Landman Abstract Consideration of spatially variable noise fields is becoming increasingly necessary in MRI given recent innovations in artifact identification and statistically driven image processing. Fast imaging methods enable study of difficult anatomical targets and improve image quality but also increase the spatial variability in the noise field. Traditional analysis techniques have either assumed that the noise is constant across the field of view (or region of interest) or have relied on separate MRI acquisitions to measure the noise field. These methods are either inappropriate for many modern scanning protocols or are overly time-consuming for already lengthy scanning sessions. We propose a new, general framework for estimating spatially variable noise fields from related, but independent MR scans that we call noise field equivalent scans. These heuristic analyses enable robust noise field estimation in the presence of artifacts. Generalization of noise estimators based on uniform regions, difference images, and maximum likelihood are presented and compared with the estimators derived from the proposed framework. Simulations of diffusion tensor imaging and T2 -relaxometry demonstrate a 10-fold reduction in mean squared error in noise field estimation, and these improvements are shown to be robust to artifact contamination. In vivo studies show that spatially variable noise fields can be readily estimated with typical data acquired at 1.5T. Magn Reson Med, 2009. © 2009 Wiley-Liss, Inc. [source] Generalization of the B *-algebra (C0(X),, ,,)MATHEMATISCHE NACHRICHTEN, Issue 1 2009Jorma Arhippainen Abstract We give a generalization of the Stone,Weierstrass property for subalgebras of C (X), with X a completely regular Hausdorff space. In particular, we study in this paper some subalgebras of C0(X), with X a locally compact Hausdorff space, provided with weighted norm topology. By using the Stone,Weierstrass property, we then describe the ideal structure of these algebras. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Generalization of a class of nonlinear averaging integral operatorsMATHEMATISCHE NACHRICHTEN, Issue 1-2 2005Teodor Bulboac Abstract Let H(U) be the space of all analytic functions in the unit disk U, and let coE denote the convex hull of the set E , ,. If K , H(U) then the operator I : K , H(U) is said to be an averaging operator if For a function h , A , H(U) we will determine simple sufficient conditions on h such that for all f , ,,1/,, where and ,,1/, represents the class of 1/, -convex functions (not necessarily normalized). As an application, we will give sufficient conditions on h to insure that the operators Ih;,,, are averaging operators on certain subsets of H(U), in order to generalize the result of [5]. In addition, some particular cases of this result obtained for appropriate choices of the function h will also be given. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Multiple Constraints and Hicksian Complementarity: A Generalization and an Application to Portfolio ChoiceMETROECONOMICA, Issue 1 2003Christian E. WeberArticle first published online: 19 MAR 200 Ian Steedman (Consumption Takes Time: Implications for Economic Theory, Routledge, London, 2001) has shown, among other things, that when a household chooses amounts of time to allocate to competing consumption activities subject to both a money income constraint and a time constraint, at least two consumption activities must have at least one compensated complement each. This paper generalizes Steedman's result in several directions and uses the generalized version to study compensated complementarity among state,dependent consumption levels and asset purchases in a model of portfolio choice under uncertainty. [source] Dispute Resolution and the Politics of Cultural GeneralizationNEGOTIATION JOURNAL, Issue 1 2003David Kahane This essay argues that generalizations about cultural identities and values should play a key role in designing procedures to resolve disputes. Generalizations about cultures are risky given the complexity of memberships and group boundaries, not to mention the power dynamics within and between social groups. But it is important to take the risk: attempts to avoid or transcend culture in resolving disputes pose an even greater danger, of reiterating the understandings of dominant cultural groups under the guise of neutrality. The author explores the "politics of cultural generalization" in theoretical terms, then considers its implications for concrete elements of dispute resolution training and process design. [source] Factors related to the inter-annual variation in plants' pollination generalization levels within a communityOIKOS, Issue 5 2010Amparo Lázaro The number of pollinators of a plant species is considered a measure of its ecological generalization and may have important evolutionary and ecological implications. Many pollination studies report inter-annual fluctuations in the composition of pollinators to particular species. However, the factors causing such variation are still poorly understood. Here we investigate how flowering duration and plant and pollinator assemblages influenced the inter-annual changes in the functional generalization level of the 20 most common plant species of a semi-natural meadow in southern Norway. We also studied the extent to which changes in generalization levels were controlled by flower-shape and flowering time. Large inter-annual changes in generalization levels were common and there was no relationship between the generalization level one year and the following. Generalization level of particular plant species increased with flowering duration, sampling effort, and the abundance of managed honeybees in the community. Generalization level decreased with the flowering synchrony between the focal plant species and the rest of the plant community and with the focal species' own abundance, which we attribute to inter-specific competition for pollinator attraction and foraging decisions made by pollinators. Plants with different flower-shapes and flowering times did not differ in the extent of inter-annual variation in generalization levels. Most studies do not consider the effect of the plant community on the generalization level of particular plant species. We show here that both pollinator and plant assemblages can affect the inter-annual variation in generalization levels of plant species. Studies like ours will help to understand how pollination interactions are structured at the community level, and the ecological and evolutionary consequences that these inter-annual changes in generalization levels may have. [source] UV Exposition During Typical Lifestyle Behavior in an Urban EnvironmentPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2010Alois W. Schmalwieser In this study the personal exposure to solar UV radiation in an urban environment was measured. Lifestyle in an urban environment is characterized by staying indoors during most of the day. Furthermore, the ambient UV radiation is mitigated by shadowing by buildings. The aim of the study was to find out activities which may contribute to UV-induced health risk in a low exposure environment. Exposure was measured during typical outdoor activities: shopping, walking, sitting in a sidewalk café, cycling, sightseeing and at an open-air pool (solar elevation: 10°,70°). Measurements were taken with an optoelectronic device which was fixed on the chest. Besides the UV Index we used the sun burn time (SBT) for risk assessments. Generalization of our results was made by calculating ratios of personal exposure to the ambient UV radiation. UV exposure was by far the highest when our study subject stayed at the swimming pool. The SBT was around 30 min for melano-compromised skin type. For all other activities, except shopping, the SBT range up to 1 h. With respect to photodamage we found that at high solar elevation (>45°) photoprotective measures should be applied for certain activities even within a city. [source] Are social competence difficulties caused by performance or acquisition deficits?PSYCHOLOGY IN THE SCHOOLS, Issue 4 2007The importance of self-regulatory mechanisms We conducted three studies which examined the performance vs. skill acquisition model of social skills deficits. In Study 1, baseline social behaviors for a random sample of 12 boys with comorbid emotional and behavioral disorders (EBD), learning disabilities (LD), language delays, and Attention Deficit Hyperactivity Disorder (ADHD) revealed that prosocial behaviors as well as inappropriate behaviors exist comorbidly in behavioral repertoires, supporting a performance rather than acquisition model of social competence difficulties. In Study 2, an ABAC design was used to examine the efficacy of a self-management intervention with noncontingent (B) and contingent (C) reinforcement for three elementary aged boys with EBD. Generalization was demonstrated in natural settings for the contingent reinforcement phase only, but was not observed over time. Study 3 replicated Study 2's procedures using an ABAC multiple baseline across participants design with a sample of adolescents with varying degrees of mental retardation. Two of the three participants responded favorably to the self-monitoring training and showed marked improvements in prosocial play skills during recess; for the third participant, no behavioral changes were observed. Results from all three studies are discussed from a social learning theory perspective. The efficacy of the data collecting procedure and implications of the results are discussed. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 351,372, 2007. [source] | |||||||||||||||||||||||||||||||||||||||||||