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In this paper, we study the full parabolic attraction–repulsion Keller–Segel model with a fractional diffusion in ℝn$$ {\mathbb{R}}^n $$ for n=2$$ n=2 $$ or 3. We are more interested in the question that whether the solutions exist globally or blow up in finite time, which was studied in the classical attraction‐repulsion Keller‐Segel model by Jin and Wang (J. Differential Equations, 2016) through constructing a suitable energy functional. However, for the fractional attraction–repulsion Keller–Segel model, it is challenging to find a similar energy functional to study the existence of the solutions. In the present paper, under the condition of ξγ=χα$$ \xi \gamma =\chi \alpha $$, we introduce the Lp$$ {L}_p $$‐ Lq$$ {L}_q $$ estimates of the fractional derivative modulus of the solution to carry out the first step of the problem. Armed with a priori estimate, it is sufficient for us to obtain the global existence of the solutions by the Moser–Alikakos iterative method and finally arrive at the decay estimates of the solutions. [ABSTRACT FROM AUTHOR]

In Wittgenstein's manuscripts dating from 1929 and 1930, there are a number of entries on the notion of probability. In this paper, I explore Wittgenstein's manuscripts between October 1929 and March 1930 and demonstrate, first, that Wittgenstein completely rejects the assumption that probability statements are based on an a priori principle. Second, I argue that the standard interpretation, which claims that Wittgenstein adopts an 'epistemological view' of probability, significantly understates the importance of Wittgenstein's development of the notion of hypotheses as a philosophical term of art. [ABSTRACT FROM AUTHOR]

This paper is concerned with the inverse problem of determining the initial value of the distributed‐order time‐fractional diffusion equation from the final time observation data, which arises in some ultra‐slow diffusion phenomena in applied areas. Since the problem is ill‐posed, we propose an iterated regularization method based on the Nesterov acceleration strategy to deal with it. Convergence rates for the regularized approximation solution are given under both the a priori and a posteriori regularization parameter choice rules. It is shown that the proposed method can always yield the order optimal convergence rates as long as the iteration parameter which appears in the Nesterov acceleration strategy is chosen large enough. In numerical aspect, the main advantage of the proposed method lies in its simplicity. Specifically, due to the Nesterov acceleration strategy, only a few number of iteration steps are required to obtain the approximation solution, and at each iteration step, we only need to numerically solve the standard initial‐boundary value problem for the distributed‐order time‐fractional diffusion equation. Some numerical examples including one‐dimensional and two‐dimensional cases are presented to illustrate the validity and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

A systematic definition of an aircraft generator's "available power" (used to supply loads on its DC bus) is given, which is defined in the context of constraints on transient and steady‐state performance. Using a geometric, data‐driven approach, such a characterisation has been achieved, and a new method, called Power availablE Estimation Tool (PEET), has been developed to determine in real‐time whether a given load can be fulfilled at a given time while maintaining power quality. This is an important problem, especially for safety critical electrical systems such as more electric aircraft, for which it is imperative to know a priori whether an added load will result in voltage variations outside of allowed values. PEET is introduced and its conceptual framework is formalised. Lastly, it provides simulation results that illustrate its performance. The results show that the PEET method produces reliable a priori estimates of power availability, and that this can be achieved within time frames that make it applicable in a real‐time implementation. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of distributed secure state estimation of a discrete‐time linear dynamical system in an adversarial environment. Much of the recent work on this problem has imposed redundancy requirements on measurement and communication networks for state estimation in the presence of attacks. In this paper, the authors aim to relax this redundancy requirement by using prior information about the state to be estimated. A scenario where sparsity information of the state is given is especially considered, and it is shown that the a priori sparsity information alleviates the redundancy requirement. An algorithm for distributed secure state estimation is then derived and a sufficient condition on the convergence of the algorithm is given. Numerical simulations finally illustrate the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

In a 1976 paper in this Journal, William Brainard and I reported the results of applying a mixed estimation procedure to the asset demand equations of savings and loan associations and mutual savings banks. In each sector, the least squares estimates were both implausible and receptive to a priori information. Even with the simplifying assumptions of normality and exchangeability, the incorporation of prior information through a mixed estimation technique yielded estimates which predicted reasonable asset responses to a wide variety of experiments. Actual root mean square errors for one to eight quarter ahead predictions were also calculated within and outside the sample period used for estimation. For savings and loans, the least squares estimates, mixed estimates and even our pure priors (using prior means for all parameters other than the intercept) forecast out of sample about equally well. Although their overall records were roughly comparable, there were some differences in forecasting particular variables a specific number of quarters ahead. Surprisingly often, one method would forecast better than another method one quarter ahead but not as well as eight quarters ahead. For mutual savings banks, the pure priors outforecast the pure data for five of the six assets in the one quarter ahead tests and were roughly comparable to least squares in the farther ahead tests. The mixed predictions were more accurate than least squares in every case but one, short term bonds one quarter ahead. For both sectors, naive autoregressive forecasts had an impressive accuracy one quarter ahead that declined dramatically as the forecasting period lengthened. A number of developments may now have made these results obsolete. The Federal Reserve Board's flow of funds data have been revised and, with the passage of time, there are now more data available. In addition, the orthogonalization routine in the computer program that we used has been changed. Computational accura... [ABSTRACT FROM AUTHOR]

In 1967, Alvin Goldman prominently claimed that the traditional JTB analysis is adequate for non‐empirical knowledge. Since then, this claim has remained widely unchallenged. In this paper, I show that this claim is false. I provide two examples in which a true belief is a priori justified but epistemically defective such that it does not constitute knowledge. Finally, I submit a novel analysis of a priori knowledge that avoids the Gettier problem. What is particularly important and distinctive about my analysis is that I neither need to make the justification condition so strong that only infallible justification is allowed, nor do I need to explicitly introduce a truth condition. [ABSTRACT FROM AUTHOR]

This paper is devoted to study a class of Kirchhoff type problems with variable exponent. By means of perturbation technique, variational methods and a priori estimation, the existence of nonnegative nontrivial solutions to this problem is obtained. [ABSTRACT FROM AUTHOR]

It is widely believed that some a priori necessary truths are not analytic in the sense of transformable by substitution of synonyms into logical truths. One much‐cited example comes from the supposed incompatibility between colour predicates. The idea is that sentences like "Nothing is both blue all over (or uniformly or at a point) and also red" are not transformable into a logical truth in the same way as "Nothing is both a bachelor and married" because the requisite conceptual link between "bachelor" and "not married" is absent between "blue" and "not red". This paper examines whether colour exclusion may be more like the bachelor case than it initially appears. It transpires that the most promising line of thought is not, however, as has been argued at length in the literature, that "blue" in some more or less convoluted way manages to mean "not red". Instead it is suggested that the requisite conceptual link may reside in the oft‐ignored qualifications ("all over", "uniformly", etc.), without which there is no incompatibility in the first place. [ABSTRACT FROM AUTHOR]

The aim of this paper is to establish a precise illustration for the structure of the nonconstant steady states for a Beddington–DeAngelis and Tanner predator–prey reaction–diffusion system with prey‐taxis. We treat the nonlinear prey‐taxis as a bifurcation parameter to analyze the bifurcation structure of the system. Furthermore, the exported global bifurcation theorem, under a rather natural condition, offers the existence of nonconstant steady states. In the proof, a priori estimates of steady states will play an important role. The local stability analysis with a numerical simulation and bifurcation analysis are given. Finally, some conclusions including biological meanings are performed to summarize our main analytic results and future investigations. [ABSTRACT FROM AUTHOR]

This paper concentrates on a priori error estimates of two monolithic schemes for Biot's consolidation model based on the three‐field formulation introduced by Oyarzúa et al. (SIAM J Numer Anal, 2016). The spatial discretizations are based on the Taylor–Hood finite elements combined with Lagrange elements for the three primary variables. We employ two different schemes to discretize the time domain. One uses the backward Euler method, and the other applies the combination of the backward Euler and Crank‐Nicolson methods. A priori error estimates show that both schemes are unconditionally convergent with optimal error orders. Detailed numerical experiments are presented to validate the theoretical analysis. [ABSTRACT FROM AUTHOR]

Summary: Mammography is a commonly used screening technique for early diagnosis of breast cancer. However, the early detection of abnormalities remains challenging, particularly for dense breast categories. In this context, the automated classification of breast masses assists radiologists in their diagnosis and give them a second opinion. In this paper, we propose a machine learning‐based method for the classification of breast masses. First, the shape and texture features are extracted from the suspicious mammogram patches. These features are then fed to the Principal Component Analysis (PCA) to keep the relevant features only and are classified using the Support Vector Machine (SVM) and Random Forest (RF). Lastly, the Apriori dynamic selection method is applied for the final test predictions using the appropriate classifier for each test sample. The classification of breast masses patches into normal and abnormal attains accuracy of 96.43%, F1‐score of 95.76%, precision of 96.29%, recall of 95.27%, specificity of 96.43%, and AUC of 0.963. Whereas the one‐stage multi‐classification of breast masses into normal, benign, and malignant achieves accuracy of 75.81%, F1‐score of 76.47%, precision of 76.85%, recall of 78.77%, specificity of 87.91%, and AUC of 0.829. [ABSTRACT FROM AUTHOR]

A universally applicable hybrid modelling method is proposed for nonlinear industrial processes that combine the a priori process knowledge with a data‐driven model. This method constructs a unified framework for the modelling process by integrating a data‐driven modelling technique, sampling detection technique, constraint optimization problem, and an evolutionary algorithm. In the modelling process, a swarm intelligence algorithm is used to optimize the model parameters under the circumstances of satisfying the constraints of a priori knowledge. By adding the constraints of process a priori knowledge, more information can be obtained about the actual process and the over‐fitting problem can be avoided to some extent, especially when modelling a system with a small quantity of samples. In order to show the effectiveness of the method proposed in this paper, two general data‐driven models, the polynomial regression model and radial basis function network model, are used as case studies. Moreover, a function simulation experiment is designed to test effectiveness, and applied to estimate average particle size of ZrO2‐TiO2 composite colloidal sols. [ABSTRACT FROM AUTHOR]

Many philosophers subscribe to the view that philosophy is a priori and in the business of discovering necessary truths from the armchair. This paper sets out to empirically test this picture. If this were the case, we would expect to see this reflected in philosophical practice. In particular, we would expect philosophers to advance mostly deductive, rather than inductive, arguments. The paper shows that the percentage of philosophy articles advancing deductive arguments is higher than those advancing inductive arguments, which is what we would expect from the vantage point of the armchair philosophy picture. The results also show, however, that the percentages of articles advancing deductive arguments and those advancing inductive arguments are converging over time and that the difference between inductive and deductive ratios is declining over time. This trend suggests that deductive arguments are gradually losing their status as the dominant form of argumentation in philosophy. [ABSTRACT FROM AUTHOR]

This paper argues that true singular existentials are rationally indubitable. After the claim is clarified and motivated (Section 1), it is defended against objections inspired by Cartesian skepticism and semantic externalism (Section 2), a Fregean fine‐grained conception of propositional content (Section 3), Kripke's causal theory of reference (Section 4), a Stalnakerian coarse‐grained conception of propositional content (Section 5), as well as Evans's account of descriptive reference fixing (Section 6). The discussion is brought to a close by concluding that either true singular existentials are a priori or apriority is not necessary for rational indubitability (Section 7). [ABSTRACT FROM AUTHOR]

This paper offers an account of concurrent liability, and in particular the existence of, and interaction between, concurrent contractual and non‐contractual duties. It argues for five essential propositions: (1) a defendant can owe simultaneous private law duties towards a claimant, the content of which overlaps in whole or in part; (2) cases of concurrent liability in contract and negligence involve independent duties, which are concurrent but not coextensive; (3) the doctrine of concurrent liability is conceptually distinct from the rule that the claimant must elect between inconsistent remedies; (4) if the defendant commits a wrong in breach of more than one duty, the claimant has a prima facie choice to sue for any of those breaches; and (5) the content of one any duty might affect the content of the other. The last of these principles, it is argued, provide an explanation for the recent decisions in Wellesley Partners v Withers and AIB v Mark Redler. [ABSTRACT FROM AUTHOR]

This paper discusses the consistent specification and estimation of asset demand equations in a disequilibrium model of financial markets. We estimate the effective asset demands of savings and loan associations, allowing for rationing in the mortgage market. These disequilibrium estimates are not very different from the estimates of notional demands with no rationing assumed. Savings and loans seem to be least affected by excess demand situations in that they are apparently not reluctant to raise mortgage rates and/or to ration borrowers. [ABSTRACT FROM AUTHOR]

We analyse the fast reaction limit in the reaction‐diffusion system with nonmonotone reaction function and one nondiffusing component. As speed of reaction tends to infinity, the concentration of the nondiffusing component exhibits fast oscillations. We identify precisely its Young measure which, as a by‐product, proves strong convergence of the diffusing component, a result that is not obvious from a priori estimates. Our work is based on an analysis of regularization for forward‐backward parabolic equations by Plotnikov. We rewrite his ideas in terms of kinetic functions which clarifies the method, brings new insights, relaxes assumptions on model functions, and provides a weak formulation for the evolution of the Young measure. © 2022 Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

The stationary solutions to the outflow problem for unipolar isentropic Navier–Stokes–Poisson system in a half line (0, ∞) have recently been shown to be asymptotically stable in13 and26, provided that all the L2 norms of initial perturbations and their derivatives are small. The main purpose of this paper is to study the asymptotic stability of the stationary solutions under large initial perturbations. First, for the outflow problem, we show that the stationary solutions are asymptotically stable, provided that only the L2 norm of initial perturbation is small. Next, for the inflow problem, we show asymptotic stability under a large initial perturbation in the H1 norm. The main ingredient in the proofs is a careful analysis in order to control the growth induced by nonlinearities of the system in a priori estimates. [ABSTRACT FROM AUTHOR]

In this paper, we study the isentropic compressible planar magnetohydrodynamic equations with viscosity depending on density and with free boundaries. Precisely, when the viscosity coefficient λ(ρ) is proportional to ρθ with θ > 0, where ρ is the density, we establish the existence of global solutions under certain assumptions on the initial data by deriving some new a priori estimates. [ABSTRACT FROM AUTHOR]

This paper explores time‐modulated metasurface‐assisted waveguide setups for the unique and accurate permittivity and permeability extraction of lossy dispersive samples with phase‐less measurements. It is theoretically demonstrated that when the position of the short‐circuit termination is dynamically modulated in a predefined way, the phase information of the reflection S‐parameter manifests itself into the amplitude level of the emerging harmonics. Being insensitive to the calibration plane shifts and phase uncertainties in reflection measurements while bypassing a priori knowledge about the material under test (MUT) and also the transmission information, can be regarded as the main advantages of the proposed time‐modulated material characterization approach. Using a simple post‐processing step, several illustrative examples are presented to numerically verify the validity of the proposed approach for some applicable and practical types of homogeneous materials. Two possible realization schemes based on mechanical actuation and electrical phase control are comprehensively discussed. An uncertainty analysis to examine how realization tolerances can affect the accuracy of results is also performed. The effectiveness of the proposed method is further experimentally demonstrated using a programmable phase‐agile metasurface. By involving the temporal dimension, the proposed strategy takes a great step forward in the phase‐less reconstruction of electromagnetic parameters. [ABSTRACT FROM AUTHOR]

Supporting a huge number of machine-to-machine devices with different priorities in Long Term Evolution networks is addressed in this paper. We propose a learning automaton (LA)-based scheme for dynamically allocating random access resources to different classes of machine-to-machine devices according to their priorities and their demands in each cycle. We then use another LA-based scheme to adjust the barring factor for each class to control the possible overload. We show that by appropriate updating procedure for these LAs, the system performance asymptotically converges to the optimal performance in which the evolved node B knows the number of access-attempting devices from each class a priori. Simulation results are provided to show the performance of the proposed scheme in random access resource allocation to defined classes and adjusting the barring factor for each of them. [ABSTRACT FROM AUTHOR]

Based on the a priori estimates in our previous work, we continue to investigate the water‐waves problem in a bounded two‐dimensional corner domain in this paper. We prove the local well‐posedness of the solution to the water‐waves system when the contact angles are less than π/16. © 2020 Wiley Periodicals LLC [ABSTRACT FROM AUTHOR]

In combination therapy, bacteria are challenged with two or more antibiotics simultaneously. Ideally, separate mutations are required to adapt to each of them, which is a priori expected to hinder the evolution of full resistance. Yet, the success of this strategy ultimately depends on how well the combination controls the growth of bacteria with and without resistance mutations. To design a combination treatment, we need to choose drugs and their doses and decide how many drugs get mixed. Which combinations are good? To answer this question, we set up a stochastic pharmacodynamic model and determine the probability to successfully eradicate a bacterial population. We consider bacteriostatic and two types of bactericidal drugs—those that kill independent of replication and those that kill during replication. To establish results for a null model, we consider non‐interacting drugs and implement the two most common models for drug independence—Loewe additivity and Bliss independence. Our results show that combination therapy is almost always better in limiting the evolution of resistance than administering just one drug, even though we keep the total drug dose constant for a 'fair' comparison. Yet, exceptions exist for drugs with steep dose–response curves. Combining a bacteriostatic and a bactericidal drug which can kill non‐replicating cells is particularly beneficial. Our results suggest that a 50:50 drug ratio—even if not always optimal—is usually a good and safe choice. Applying three or four drugs is beneficial for treatment of strains with large mutation rates but adding more drugs otherwise only provides a marginal benefit or even a disadvantage. By systematically addressing key elements of treatment design, our study provides a basis for future models which take further factors into account. It also highlights conceptual challenges with translating the traditional concepts of drug independence to the single‐cell level. [ABSTRACT FROM AUTHOR]

This paper describes the development of an integrated intelligent (expert) system and conventional information system to support decision making of a diagnostic decision in a multi-agent environment. It argues that many a priori requirements for the information system can be elicited by accounting for the specific nature of the diagnostic decision and for the single/multiple-actor environment. This finding is generalized to a framework that indicates that a priori requirements take into account the basic theories on which the information system supporting the decision task is ultimately based. In particular, attention is focused on the nature of the task (e.g. diagnostic), whether the application is for a single- or multiple-agent situation and the nature of the multi-agent structure (e.g. product or functional form of organization). [ABSTRACT FROM AUTHOR]

In this paper, we present a collection of a priori estimates of the electromagnetic field scattered by a general bounded domain. The constitutive relations of the scatterer are in general anisotropic. Surface averages are investigated, and several results on the decay of these averages are presented. The norm of the exterior Calderón operator for a sphere is investigated and depicted as a function of the frequency. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we generalize the W2,p interior estimates of fully nonlinear elliptic equations that were obtained by Caffarelli ['Interior a priori estimates for solutions of fully nonlinear equations', Ann. of Math. 130 (1989) 189-213]. The generalizations are carried out in two directions. One is that we relax the regularity requirement on the 'constant coefficients' equations and the other one is that we broaden the range of p. [ABSTRACT FROM AUTHOR]

In this paper, an inverse problem for space-fractional backward diffusion equation, which is highly ill-posed, is considered. This problem is obtained from the classical diffusion equation by replacing the second-order space derivative with a Riesz-Feller derivative of order α ∈ (0,2]. We show that such a problem is severely ill-posed, and further present a simplified Tikhonov regularization method to deal with this problem. Convergence estimate is presented under a priori choice of regularization parameter. Numerical experiments are given to illustrate the accuracy and efficiency of the proposed method. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we consider the time‐dependent Stokes problem in a three‐dimensional domain with mixed boundary conditions. The discretization relies on spectral methods with respect to the space variables and Euler's implicit scheme with respect to the time variable, then by the second order BDF method. A detailed numerical analysis leads to a priori error estimates for each numerical scheme. [ABSTRACT FROM AUTHOR]

The paper develops a conception of epistemic warrant as applied to perceptual belief, called "entitlement", that does not require the warranted individual to be capable of understanding the warrant. The conception is situated within an account of animal perception and unsophisticated perceptual belief. It characterizes entitlement as fulfillment of an epistemic norm that is apriori associated with a certain representational function that can be known apriori to be a function of perception. The paper connects antiindividualism, a thesis about the nature of mental states, and perceptual entitlement. It presents an argument that explains the objectivity and validity of perceptual entitlement partly in terms of the nature of perceptual states—hence the nature of perceptual beliefs, which are constitutively associated with perceptual states. The paper discusses ways that an individual can be entitled to perceptual belief through its connection to perception, and ways that entitlement to perceptual belief can be undermined. [ABSTRACT FROM AUTHOR]

This paper examines the Cauchy problem for doubly singular parabolic equation with a source term depending solely on the gradient. We establish the local and global existence of solutions when initial data is merely a function in Llocr(RN) (r ≥ 1). Moreover, the uniform L∞-estimates and gradient estimates of solutions are obtained. [ABSTRACT FROM AUTHOR]

Throughout his career, Derek Parfit made the bold suggestion, at various times under the heading of the "Normativity Objection," that anyone in possession of normative concepts is in a position to know, on the basis of their competence with such concepts alone, that reductive realism in ethics is not even possible. Despite the prominent role that the Normativity Objection plays in Parfit's non‐reductive account of the nature of normativity, when the objection hasn't been ignored, it's been criticized and even derided. We argue that the exclusively negative attention that the objection has received has been a mistake. On our reading, Parfit's Normativity Objection poses a serious threat to reductivism, as it exposes the uneasy relationship between our a priori knowledge of a range of distinctly normative truths and the package of semantic commitments that reductivists have typically embraced since the Kripkean revolution. [ABSTRACT FROM AUTHOR]

Purpose: This paper introduces a method that maximizes the probability of satisfying the clinical goals in intensity-modulated radiation therapy treatments subject to setup uncertainty. Methods: The authors perform robust optimization in which the clinical goals are constrained to be satisfied whenever the setup error falls within an uncertainty set. The shape of the uncertainty set is included as a variable in the optimization. The goal of the optimization is to modify the shape of the uncertainty set in order to maximize the probability that the setup error will fall within the modified set. Because the constraints enforce the clinical goals to be satisfied under all setup errors within the uncertainty set, this is equivalent to maximizing the probability of satisfying the clinical goals. This type of robust optimization is studied with respect to photon and proton therapy applied to a prostate case and compared to robust optimization using an a priori defined uncertainty set. Results: Slight reductions of the uncertainty sets resulted in plans that satisfied a larger number of clinical goals than optimization with respect to a priori defined uncertainty sets, both within the reduced uncertainty sets and within the a priori, nonreduced, uncertainty sets. For the prostate case, the plans taking reduced uncertainty sets into account satisfied 1.4 (photons) and 1.5 (protons) times as many clinical goals over the scenarios as the method taking a priori uncertainty sets into account. Conclusions: Reducing the uncertainty sets enabled the optimization to find better solutions with respect to the errors within the reduced as well as the nonreduced uncertainty sets and thereby achieve higher probability of satisfying the clinical goals. This shows that asking for a little less in the optimization sometimes leads to better overall plan quality. [ABSTRACT FROM AUTHOR]

Digital holographic microscope allows imaging of opaque and transparent specimens without staining. A digitally recorded hologram must be reconstructed numerically at the actual depth of the object to obtain a focused image. We have developed a high-resolution digital holographic microscope for imaging amplitude and phase objects with autofocusing capability. If the actual depth of an object is not known a priori, it is estimated by comparing the sharpness of several reconstructions at different distances, which is very demanding in means of computational power when the recorded hologram is large. In this paper, we present 11 different sharpness metrics for estimating the actual focus depths of objects. The speed performance of focusing is discussed, and a scaling technique is introduced where the speed of autofocusing increases on the order of square of the scale ratio. We measured the performance of scaling on computer-generated holograms and on recorded holograms of a biological sample. We show that simulations are in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

SUMMARY The application of the XFEM to fracture mechanics is effective, because a crack can be modeled independently from the meshes and a complex remeshing procedure can be avoided. However, the classical XFEM has an essential problem in the approximation of partially enriched elements, that is, blending elements, which causes a lack of accuracy. For the weighted XFEM, although the numerical results show the effective improvements, it was found that the issue of blending elements still remains upon detailed examination. In the present paper, the PU-XFEM is formulated as an explicit application of the partition of unity (PU) approach to the XFEM, in order to precisely reproduce a priori knowledge of the solution by enrichment. The PU-XFEM is applied to two-dimensional linear fracture mechanics, and its effectiveness is verified. It is consequently found out that the PU-XFEM precisely reproduces a priori knowledge of the solution and is therefore effective to completely solve the problem of the blending elements. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An uncertain (scalar, vector, tensor) field is usually perceived as a discrete random field with a priori unknown probability distributions. To compute derived probabilities, e.g. for the occurrence of certain features, an appropriate probabilistic model has to be selected. The majority of previous approaches in uncertainty visualization were restricted to Gaussian fields. In this paper we extend these approaches to nonparametric models, which are much more flexible, as they can represent various types of distributions, including multimodal and skewed ones. We present three examples of nonparametric representations: (a) empirical distributions, (b) histograms and (c) kernel density estimates (KDE). While the first is a direct representation of the ensemble data, the latter two use reconstructed probability density functions of continuous random variables. For KDE we propose an approach to compute valid consistent marginal distributions and to efficiently capture correlations using a principal component transformation. Furthermore, we use automatic bandwidth selection, obtaining a model for probabilistic local feature extraction. The methods are demonstrated by computing probabilities of level crossings, critical points and vortex cores in simulated biofluid dynamics and climate data. [ABSTRACT FROM AUTHOR]

Herein, we present data from two studies of Twitter usage in different postsecondary courses with the goal of analyzing the relationships surrounding student engagement and collaboration as they intersect learning outcomes. Study 1 was conducted with 125 students taking a first-year seminar course, half of who were required to use Twitter while the other half used Ning. Study 2 was conducted with 135 students taking a large lecture general education course where Twitter participation was voluntary. Faculty in Study 1 engaged with students on Twitter in activities based on an a priori theoretical model, while faculty in Study 2 only engaged students sporadically on the platform. Qualitative analyses of tweets and quantitative outcomes show that faculty participation on the platform, integration of Twitter into the course based on a theoretically driven pedagogical model and requiring students to use Twitter are essential components of improved outcomes. Practitioner notes What is already known about this topic Student use of social media is integrally related to how students engage the world., Little research exists on how social media use is linked to college student engagement in relation to academic outcomes., One study using a controlled design demonstrated a relationship between Twitter use and student engagement., What this paper adds An empirical comparison of two ways in which Twitter was differently integrated into college courses., The utilization of quantitative and qualitative data to assess real-world academic outcomes related to Twitter use., Evidence-based best practices for using Twitter in educationally relevant and productive ways., Implications for practice and/or policy If integrating Twitter in their courses, faculty should require and structure its use along educationally relevant criteria., To achieve the most effective results, faculty should have a theoretically driven pedagogical basis for incorporating Twitter., Faculty should actively engage with students on the platform to obtain maximum benefit. [ABSTRACT FROM AUTHOR]

A novel adaptive B-Spline deformable model is presented in this paper for object segmentation. Comparing with other B-Spline models, the proposed model has the following advantages. First, a fully automatic and affine-invariant strategy is proposed for landmark point assignment. Second, contrary to other B-Spline models that rely on predetermined number of control points, an automatic scheme for control point insertion is designed to enhance the adaptivity and the flexibility of B-Spline model for segmenting shapes with high complexity. Thirdly, a statistical framework is embedded for modeling the shape distribution and appearance characteristics of landmark points in the training samples. Fine deformation can be achieved through the minimum mean square error approach that allows the model to accurately adapt to the desired object boundaries in the image. Experiments on medical image segmentation are carried out to validate the performance, and comparison has been made with respect to the traditional Snake and ASM. It turns out that the proposed adaptive B-Spline model can attain more accurate object segmentation. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper provides an introduction to a recently developed conceptual framework—the dimensional–categorical spectrum—for utilizing general factor mixture models to explore the latent structures of psychological constructs. This framework offers advantages over traditional latent variable models that usually employ either continuous latent factors or categorical latent class variables to characterize the latent structure and require an a priori assumption about the underlying nature of the construct as either purely dimension or purely categorical. The modeling process is discussed in detail and then illustrated with data on the delinquency items of Achenbach's child behavior checklist from a sample of children in the National Adolescent and Child Treatment Study. [ABSTRACT FROM AUTHOR]

This paper presents a new perspective on the management of outcomes and processes in a knowledge team's work. Knowledge teams frequently face complex, open-ended tasks for which the a priori specification of goals and work processes is not possible. Such teams must define these work elements themselves; emphasizing one over the other can lead a team to become either outcome-or process-focused, with implications for the level at which they identify their activities and the flexibility with which they conduct work. A survey study of student teams and a field study of organizational teams test the effects of outcome versus process focus on performance. Consistent with prior findings, the first study demonstrates that outcome focus is positively related to performance on complex, open-ended tasks and that team members' level of action identification mediates the effects of outcome and process focus on performance. Action research conducted as part of the second study demonstrates the importance of early events in a team's life cycle and the challenge for managers who hope to influence their teams to have a greater degree of focus on outcomes over process. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, a partial supervision strategy for a recently developed clustering algorithm, the nearest neighbour clustering algorithm (NNCA), is proposed. The proposed method (NNCA-PS) offers classification capability with a smaller amount of a priori knowledge, where a small number of data objects from the entire data set are used as labelled objects to guide the clustering process towards a better search space. Experimental results show that NNCA-PS gives promising results of 89% sensitivity at 95% specificity when used to segment retinal blood vessels, and a maximum classification accuracy of 99.5% with 97.2% average accuracy when applied to a breast cancer data set. Comparisons with other methods indicate the robustness of the proposed method in classification. Additionally, experiments on parallel environments indicate the suitability and scalability of NNCA-PS in handling larger data sets. [ABSTRACT FROM AUTHOR]

The size, shape and number of seamounts, once detected and isolated from other features such as oceanic plateaus or trenches, have the potential to provide valuable constraints on important solid Earth processes, e.g. oceanic volcanism. The variability of seamount size and morphology, however, presents problems for computational approaches to seamount isolation. This paper develops a novel and efficient wavelet-based seamount detection routine ‘Spatial Wavelet Transform (SWT)’; the first use of multiple scales of analysis to directly isolate edifices from bathymetric data. Only weak shape-related criteria are used and no a priori knowledge of the scale and location of the seamounts is required. For a bathymetric profile collected on cruise v3312 SWT matches, to within 25%, the dimensions of five times the number of the features determined by manual inspection than does the best statistically based (e.g. mean, median or mode) sliding window filter. The size–frequency distribution, a key descriptor of seamount populations, is also much better estimated by the SWT method. As such, the SWT represents a step towards the goal of objective and robust quantification and classification of seamounts. [ABSTRACT FROM AUTHOR]

In Philosophical Investigations, Wittgenstein argues that we can neither say of the standard One Metre in Paris that it is a single metred length, nor that it is not. Kripke's reply to the puzzle is well known: the sentence expressing the assertion that the standard One Metre is one metre in length (at time t0) is a true, a priori and contingent sentence. In this paper, I would like to show the nature of the intuition that runs behind Kripke's reply to the puzzle, and why, in the final analysis, it is not satisfactory, with respect to the point made by Wittgenstein. In addition, I will show that the case of the One Metre in Paris exemplifies the radical break Wittgenstein makes with traditional concepts of meaning. I then draw a general lesson that shows that the structure of concepts and functions (measures) in Wittgenstein is given by the idea of an arbitrary choice of “an object of comparison.” Concepts and functions (measures) are materialised and internalised in the form of objects that are arbitrarily sampled from a sample space of same logical-type objects. [ABSTRACT FROM AUTHOR]

Between 1992 and 2000, seven insect agents were released in Australia for the biological control of Onopordum spp. thistles. This paper describes the protocol used for the selection of these agents, starting with the development of a preliminary strategy, based on the ecology and population dynamics of the target weed. The strategy informed the surveys for natural enemies in the native range of Onopordum, targeting insects that attacked key transitional stages of the weed’s life cycle. Ongoing studies of Onopordum populations in both Australia and Europe, plus experimental studies on the ecology, potential impact and preliminary host specificity of the agents, led to the refinement of the strategy and the selection and prioritisation of the agents. It is argued that development of an explicit strategy prior to release should be encouraged, as it forces researchers to revisit the rationale for and aims of particular biological control projects, ensuring that the process of agent selection remains focused. It also provides a tool to improve the process of agent selection, as subsequent results can be measured against the strategy and agent success or failure evaluated against the a priori expectations. [ABSTRACT FROM AUTHOR]

The argument known as the ‘McKinsey Recipe’ tries to establish the incompatibility of semantic externalism (about natural kind concepts in particular) and a priori self-knowledge about thoughts and concepts by deriving from the conjunction of these theses an absurd conclusion, such as that we could know a priori that water exists. One reply to this argument is to distinguish two different readings of ‘natural kind concept’: (i) a concept which in fact denotes a natural kind, and (ii) a concept which aims to denote a natural kind. Paul Boghossian has argued, using a Dry Earth scenario, that this response fails, claiming that the externalist cannot make sense of a concept aiming, but failing, to denote a natural kind. In this paper I argue that Boghossian’s argument is flawed. Borrowing machinery from two-dimensional semantics, using the notion of ‘considering a possible world as actual’, I claim that we can give a determinate answer to Boghossian’s question: which concept would ‘water’ express on Dry Earth?1 [ABSTRACT FROM AUTHOR]

In this article the author comments on the research paper titled "Implicit Belief and A Priori Knowledge," by John Hawthorne. The author states that Hawthorne centered his research on the point that implicit knowledge is an integral part of epistemology. He mentions that contextualism as presented by Hawthorne is not supported by contemporary contextualism. Additionally he comments on intuitionism, semanticism, reliabilism and primitivism as presented by Hawthorne.

In this article the author comments on the research paper of Pat Manfredi that discusses the modesty and a priori knowledge. He states that in his thesis Menfredi presents three controversial issues of a priori knowledge, justification required in a priori and empirical defeasibility of a priori. The author comments on the importance of believing in the beliefs that determines a priori and justification.

A semi‐Lagrangian unified finite element method is investigated for solving time‐dependent coupled Darcy‐transport problems. In this method, the modified method of characteristics is combined with a Galerkin finite element discretization allowing the same finite element space to be used for all solutions of the problem including the pressure, velocity and concentration. Convergence and stability of the method are also analyzed in this study and error estimates in the L2$$ {L}^2 $$‐norm are established for the numerical solutions. For the time integration we consider a second‐order implicit method and discrete error estimates are provided. Due to the Lagrangian treatment of convection terms in the considered problems, the conventional Courant‐Friedrichs‐Lewy condition is relaxed and the time truncation errors are reduced in the diffusion‐reaction part. Numerical results are presented for several test examples to demonstrate the reliability and efficiency of the proposed method. The computed results support our expectations for an accurate and highly efficient semi‐Lagrangian unified finite element method for time‐dependent coupled Darcy‐transport problems. [ABSTRACT FROM AUTHOR]

In this article, we have developed the mixed virtual element formulation for the nonlocal parabolic problem. A priori error estimates for the semi‐discrete and the fully‐discrete schemes are derived and analyzed. The spatial discretization is based on the mixed virtual element framework, and the backward Euler method is used for the time discretization. Using Brouwer's fixed point argument, we have proved the existence and uniqueness of a fully‐discrete scheme. A set of representative numerical examples investigates such theoretical results. [ABSTRACT FROM AUTHOR]

The pressure correction scheme is combined with interior penalty discontinuous Galerkin method to solve the time‐dependent Navier–Stokes equations. Optimal error estimates are derived for the velocity in the L2 norm in time and in space. Error bounds for the discrete time derivative of the velocity and for the pressure are also established. The analysis is challenging and technical and is based on appropriate use of lift operators and duality arguments. [ABSTRACT FROM AUTHOR]