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A numerical method for solving the Cauchy problem for all the six Painlevé equations is proposed. The difficulty of solving these equations is that the unknown functions can have movable (that is, dependent on the initial data) singular points of the pole type. Moreover, the Painlevé III-VI equations may have singularities at points where the solution takes certain finite values. The positions of all these singularities are not a priori known and are determined in the process of solving the equation. The proposed method is based on the transition to auxiliary systems of differential equations in neighborhoods of the indicated points. The equations in these systems and their solutions have no singularities at the corresponding point and its neighborhood. Such auxiliary equations are derived for all Painlevé equations and for all types of singularities. Efficient criteria for transition to auxiliary systems are formulated, and numerical results illustrating the potentials of the method are presented. [ABSTRACT FROM AUTHOR]

RFID technologies are gaining much attention as they are attractive solutions to many applications. Localization based on active RFID technologies provides a much needed added-value to further expand the application domain. LANDMARC was the first attempt using active RFID for indoor location sensing with satisfactory results. However, the LANDMARC approach suffers from two drawbacks. First, it does not work well in a closed area with severe radio signal multi-path effects. Second, to further improve the localization accuracy, more reference tags are required which is costly and may trigger the RF interference phenomenon. The proposed VIRE approach can overcome the above drawbacks without any additional cost. Based on the concept of virtual reference tags, a proximity map is maintained by each reader. An elimination algorithm is used to eliminate those unlikely locations to reduce the estimation error. Our experimental results show that the new method consistently enhances the precision of indoor localization from 17 to 73 percent over the LANDMARC approach at different tag locations in different environments. [ABSTRACT FROM AUTHOR]

The first part of this article shows that qualitative comparative analysis (QCA)—also in its most recent form as in Ragin (2008)—does not correctly analyze data generated by causal chains. The incorrect modeling of data originating from chains essentially stems from QCA’s reliance on Quine-McCluskey optimization to eliminate redundancies from sufficient and necessary conditions. Baumgartner (2009a, 2009b) has introduced a Boolean methodology, termed coincidence analysis (CNA), which is related to QCA, yet, contrary to the latter, does not eliminate redundancies by means of Quine-McCluskey optimization. The second part of the article applies CNA to chain-generated data. It turns out that CNA successfully detects causal chains in small-n data. [ABSTRACT FROM AUTHOR]

Multivariate polynomials are usually discussed in the framework of algebraic geometry. Solving problems in algebraic geometry usually involves the use of a Gröbner basis. This article shows that linear algebra without any Gröbner basis computation suffices to solve basic problems from algebraic geometry by describing three operations: multiplication, division, and elimination. This linear algebra framework will also allow us to give a geometric interpretation. Multivariate division will involve oblique projections, and a link between elimination and principal angles between subspaces (CS decomposition) is revealed. The main computational tool in this approach is the QR decomposition. [ABSTRACT FROM AUTHOR]

We present an advanced design methodology for pulse-width-modulated (PWM) DC-AC signal generation. Using design methods based on the Walsh transform, AC sinusoidal signals can be approximated by suitable PWM signals. For different AC amplitudes, the switching instants of the PWM signals can be efficiently computed by using appropriate systems of explicit linear equations. However, the equation systems provided by conventional implementations of this approach are typically only valid for a restricted interval of AC amplitudes and, in general, a supervised implementation of several equation systems is necessary to cover the full AC amplitude range. Additionally, obtaining suitable equation systems for designs with a large number of switching instants requires solving a complex optimization problem. In defining the constitutive pulses of a PWM signal, a suitable partition of the time interval is used as a reference system. In the new methodology, pulses are chosen to be symmetric with respect to the partition points, and the switching times are specified by means of switching ratios with respect to the endpoint subintervals. This approach leads to particularly simple Walsh series representations, introduces a remarkable computational simplification, and achieves excellent results in reducing the harmonic distortion. [ABSTRACT FROM AUTHOR]

SUMMARY The most efficient way to parallelize computation is to build and evaluate the task graph constrained only by the data dependencies between the tasks. Both Intel's C++ Concurrent Collections (CnC) and Threading Building Blocks (TBB) libraries allow such task-based parallel programming. CnC also adapts the macro data flow model by providing only single-assignment data objects in its global data space. Although CnC makes parallel programming easier, by specifying data flow dependencies only through single-assignment data objects, its macro data flow model incurs overhead. Intel's C++ CnC library is implemented on top of its C++ TBB library. We can measure the overhead of CnC by comparing its performance with that of TBB. In this paper, we analyze all three types of data dependencies in the tiled in-place Gauss-Jordan elimination algorithm for the first time. We implement the task-based parallel tiled Gauss-Jordan algorithm in TBB using the data dependencies analyzed and compare its performance with that of the CnC implementation. We find that the overhead of CnC over TBB is only 12 %- 15 % of the TBB time, and CnC can deliver as much as 87 %- 89 % of the TBB performance for Gauss-Jordan elimination, using the optimal tile size. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Proof search has been used to specify a wide range of computation systems. In order to build a framework for reasoning about such specifications, we make use of a sequent calculus involving induction and co-induction. These proof principles are based on a proof-theoretic (rather than set-theoretic) notion of definition (Hallnäs, 1991 [18], Eriksson, 1991 [11], Schroeder-Heister, 1993 [38], McDowell and Miller, 2000 [22]). Definitions are akin to logic programs, where the left and right rules for defined atoms allow one to view theories as “closed” or defining fixed points. The use of definitions and free equality makes it possible to reason intensionally about syntax. We add in a consistent way rules for pre- and post-fixed points, thus allowing the user to reason inductively and co-inductively about properties of computational system making full use of higher-order abstract syntax. Consistency is guaranteed via cut-elimination, where we give a direct cut-elimination procedure in the presence of general inductive and co-inductive definitions via the parametric reducibility technique. [Copyright &y& Elsevier]

Lean manufacturing is a manufacturing system aimed at waste elimination thereby streamlining the process. Leanness is the performance measure of lean manufacturing. The measurement of leanness necessitates fuzzy logic, due of the existence of impreciseness and vagueness. The calculation of leanness using fuzzy logic manually is a time consuming and highly repetitive job. To overcome this, fuzzy logic-based inference method has been attempted in this research study. A conceptual model consisting of three levels namely enabler, criterion, and attributes has been developed. Then the linguistic variables are assigned and the membership functions are defined. Leanness level has been computed using IF-THEN rules based interface method. This is followed by gap analysis to identify the weaker criteria. Then suitable proposals have been derived to overcome these obstacles towards leanness improvement of the organization. [ABSTRACT FROM AUTHOR]

We characterize epistemic consequences of truthful communication among rational agents in a game-theoretic setting. To this end we introduce normal-form games equipped with an interaction structure, which specifies which groups of players can communicate their preferences with each other. We then focus on a specific form of interaction, namely a distributed form of iterated elimination of strictly dominated strategies (IESDS), driven by communication among the agents. We study the outcome of IESDS after some (possibly all) messages about players' preferences have been sent. The main result of the paper, Theorem 4, provides an epistemic justification of this form of IESDS. [ABSTRACT FROM AUTHOR]

In the proof-theoretic semantics approach to meaning, harmony, requiring a balance between introduction-rules (I-rules) and elimination rules (E-rules) within a meaning conferring natural-deduction proof-system, is a central notion. In this paper, we consider two notions of harmony that were proposed in the literature: 1. GE-harmony, requiring a certain form of the E-rules, given the form of the I-rules. 2. Local intrinsic harmony: imposes the existence of certain transformations of derivations, known as reduction and expansion. We propose a construction of the E-rules (in GE-form) from given I-rules, and prove that the constructed rules satisfy also local intrinsic harmony. The construction is based on a classification of I-rules, and constitute an implementation to Gentzen's (and Pawitz') remark, that E-rules can be 'read off' I-rules. [ABSTRACT FROM AUTHOR]

Valentini (1983) has presented a proof of cut-elimination for provability logic GL for a sequent calculus using sequents built from sets as opposed to multisets, thus avoiding an explicit contraction rule. From a formal point of view, it is more syntactic and satisfying to explicitly identify the applications of the contraction rule that are ‘hidden’ in proofs of cut-elimination for such sequent calculi. There is often an underlying assumption that the move to a proof of cut-elimination for sequents built from multisets is straightforward. Recently, however, it has been claimed that Valentini’s arguments to eliminate cut do not terminate when applied to a multiset formulation of the calculus with an explicit rule of contraction. The claim has led to much confusion and various authors have sought new proofs of cut-elimination for GL in a multiset setting.Here we refute this claim by placing Valentini’s arguments in a formal setting and proving cut-elimination for sequents built from multisets. The use of sequents built from multisets enables us to accurately account for the interplay between the weakening and contraction rules. Furthermore, Valentini’s original proof relies on a novel induction parameter called “width” which is computed ‘globally’. It is difficult to verify the correctness of his induction argument based on “width.” In our formulation however, verification of the induction argument is straightforward. Finally, the multiset setting also introduces a new complication in the case of contractions above cut when the cut-formula is boxed. We deal with this using a new transformation based on Valentini’s original arguments.Finally, we discuss the possibility of adapting this cut-elimination procedure to other logics axiomatizable by formulae of a syntactically similar form to the GL axiom. [ABSTRACT FROM AUTHOR]

A normalization procedure is given for classical natural deduction with the standard rule of indirect proof applied to arbitrary formulas. For normal derivability and the subformula property, it is sufficient to permute down instances of indirect proof whenever they have been used for concluding a major premiss of an elimination rule. The result applies even to natural deduction for classical modal logic. [ABSTRACT FROM AUTHOR]

In this paper we inject four Hilbert functions in the determination of the defining equations of the Rees algebra of almost complete intersections of finite co-length. Because three of the corresponding modules are Artinian, some of these relationships are very effective, with the novel approach opening up tracks to the determination of the equations and also to processes of going from homologically defined sets of equations to higher degrees ones. While not specifically directed towards the extraction of elimination equations, it will show how some of these arise naturally. [ABSTRACT FROM AUTHOR]

Let T be a first-order theory. A correspondence is established between internal covers of models of T and definable groupoids within T . We also consider amalgamations of independent diagrams of algebraically closed substructures, and find strong relation between covers, uniqueness for 3-amalgamation, existence of 4-amalgamation, imaginaries of Tσ, and definable groupoids. As a corollary, we describe the imaginary elements of families of finite-dimensional vector spaces over pseudo-finite fields. [ABSTRACT FROM AUTHOR]

In this paper, we describe a code transformation technique that, given a code for a vector function F, produces a code suitable for computing collections of Jacobian-vector products F′(x)x˙ or Jacobian-transpose-vector products F′(x)T y¯. Exploitation of scarcity – a measure of the degrees of freedom in the Jacobian matrix – requires solving a combinatorial optimization problem that is believed to be hard. Our heuristics transform the computational graph for F, producing, in the form of a transformed graph G′, a representation of the Jacobian F′(x) that is both concise and suitable for evaluating large collections of the Jacobian-vector products or the Jacobian-transpose-vector products. Our heuristics are randomized and compare favourably in all cases with the best known heuristics. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a multi-modal polymorphic type theory to model epistemic processes characterized by trust, defined as a second-order relation affecting the communication process between sources and a receiver. In this language, a set of senders is expressed by a modal prioritized context, whereas the receiver is formulated in terms of a contextually derived modal judgement. Introduction and elimination rules for modalities are based on the polymorphism of terms in the language. This leads to a multi-modal non-homogeneous version of a type theory, in which we show the embedding of the modal operators into standard group knowledge operators. [Copyright &y& Elsevier]

Abstract: State-of-the-art software packages for solving large-scale linear systems are predominantly founded on Gaussian elimination techniques (e.g. LU-decomposition). This paper presents an efficient framework for solving large-scale linear systems by means of a novel utilization of Cramerʼs rule. While the latter is often perceived to be impractical when considered for large systems, it is shown that the algorithm proposed retains an complexity with pragmatic forward and backward stability properties. Empirical results are provided to substantiate the stated accuracy and computational complexity claims. [Copyright &y& Elsevier]

The first and second order of accuracy stable difference schemes for the numerical solution of the mixed problem for the fractional parabolic equation are presented. Stability and almost coercive stability estimates for the solution of these difference schemes are obtained. A procedure of modified Gauss elimination method is used for solving these difference schemes in the case of one-dimensional fractional parabolic partial differential equations. [ABSTRACT FROM AUTHOR]

Abstract: The dichromatic polynomial can be characterized as the most general C-invariant, i.e., a graph polynomial satisfying a linear recurrence with respect to edge deletion and edge contraction. Similarly, the universal edge elimination polynomial introduced in [Ilya Averbouch, Benny Godlin, and Johann A. Makowsky. An extension of the bivariate chromatic polynomial. Eur. J. Comb, 31(1):1–17, 2010] can be characterized as the most general EE-invariant, i.e., a graph polynomial satisfying a linear recurrence with respect to edge deletion, edge contraction and edge extraction. In this paper we examine substitution instances of and show that among these the dichromatic polynomial plays a distinctive rôle. [Copyright &y& Elsevier]

We analyze a class of matrices generalizing strictly diagonally dominant matrices and included in the important class of H-matrices. Adequate pivoting strategies and the corresponding Schur complements are studied. A new class of matrices with all their principal minors positive is presented. [ABSTRACT FROM AUTHOR]

An optimal stopping problem of Markov chain with infinite horizon is considered. For the case of finite number m of states, Sonin proposed an algorithm, which allows to find the value function and the stopping set in not more than steps. The algorithm is based on a modification of Markov chain on each step, related with the elimination of the states which certainly belong to the continuation set. To solve the problem with arbitrary state space and to have a possibility of generalization to the continuous time, one needs to modify the procedure. We propose a procedure which is based on a sequential modification of the pay-off function for the same chain in such a way, that the value function is the same for both problems and the modified pay-off function is greater than the initial one on some set and is equal to it on the complement. We show the efficiency of this procedure. [ABSTRACT FROM AUTHOR]

There is a well-known connection between the three problems related to the optimal stopping of Markov chains and the equality of three corresponding indices: the classical Gittins index (GI) in the ratio maximization problem, the Kathehakis–Veinott index in a restart problem and Whittle index in a family of retirement problems. In Sonin [Statist. Probab. Lett. 78 (12,1) (2008), pp. 1526–1533], these three problems and these three indices were generalized in such a way that it became possible to use the state elimination algorithm [Sonin, Math. Meth of Oper. Res. (1999), pp. 111–123] to calculate this common generalized GI α. The main goal of this note is to demonstrate that the equality of these (generalized) indices is a special case of a more general relation between three simple abstract optimization problems. [ABSTRACT FROM AUTHOR]

We study a system, called NEL, which is the mixed commutative/noncommutative linear logic BV augmented with linear logic's exponentials. Equivalently, NEL is MELL augmented with the noncommutative self-dual connective seq. In this article, we show a basic compositionality property of NEL, which we call decomposition. This result leads to a cut-elimination theorem, which is proved in the next article of this series. To control the induction measure for the theorem, we rely on a novel technique that extracts from NEL proofs the structure of exponentials, into what we call !-?-Flow-Graphs. [ABSTRACT FROM AUTHOR]

We consider the problem of computing an approximate minimum cycle basis of an undirected non-negative edge-weighted graph G with m edges and n vertices; the extension to directed graphs is also discussed. In this problem, a {0,1} incidence vector is associated with each cycle and the vector space over $\mathbb{F}_{2}$ generated by these vectors is the cycle space of G. A set of cycles is called a cycle basis of G if it forms a basis for its cycle space. A cycle basis where the sum of the weights of the cycles is minimum is called a minimum cycle basis of G. Cycle bases of low weight are useful in a number of contexts, e.g. the analysis of electrical networks, structural engineering, chemistry, and surface reconstruction. Although in most such applications any cycle basis can be used, a low weight cycle basis often translates to better performance and/or numerical stability. Despite the fact that the problem can be solved exactly in polynomial time, we design approximation algorithms since the performance of the exact algorithms may be too expensive for some practical applications. We present two new algorithms to compute an approximate minimum cycle basis. For any integer k≥1, we give (2 k−1)-approximation algorithms with expected running time O( kmn+ mn) and deterministic running time O( n), respectively. Here ω is the best exponent of matrix multiplication. It is presently known that ω<2.376. Both algorithms are o( m) for dense graphs. This is the first time that any algorithm which computes sparse cycle bases with a guarantee drops below the Θ( m) bound. We also present a 2-approximation algorithm with expected running time $O(m^{\omega}\sqrt{n\log n})$ , a linear time 2-approximation algorithm for planar graphs and an O( n) time 2.42-approximation algorithm for the complete Euclidean graph in the plane. [ABSTRACT FROM AUTHOR]

I here argue that Ted Sider's indeterminacy argument against vagueness in quantifiers fails. Sider claims that vagueness entails precisifications, but holds that precisifications of quantifiers cannot be coherently described: they will either deliver the wrong logical form to quantified sentences, or involve a presupposition that contradicts the claim that the quantifier is vague. Assuming (as does Sider) that the 'connectedness' of objects can be precisely defined, I present a counter-example to Sider's contention, consisting of a partial, implicit definition of the existential quantifier that in effect sets a given degree of connectedness among the putative parts of an object as a condition upon there being something (in the sense in question) with those parts. I then argue that such an implicit definition, taken together with an 'auxiliary logic' (e.g., introduction and elimination rules), proves to function as a precisification in just the same way as paradigmatic precisifications of, e.g., 'red'. I also argue that with a quantifier that is stipulated as maximally tolerant as to what mereological sums there are, precisifications can be given in the form of truth-conditions of quantified sentences, rather than by implicit definition. [ABSTRACT FROM AUTHOR]

This paper investigates a generalized version of inquisitive semantics. A complete axiomatization of the associated logic is established, the connection with intuitionistic logic and several intermediate logics is explored, and the generalized version of inquisitive semantics is argued to have certain advantages over the system that was originally proposed by Groenendijk () and Mascarenhas (). [ABSTRACT FROM AUTHOR]

The interpretation of implications as rules motivates a different left-introduction schema for implication in the sequent calculus, which is conceptually more basic than the implication-left schema proposed by Gentzen. Corresponding to results obtained for systems with higher-level rules, it enjoys the subformula property and cut elimination in a weak form. [ABSTRACT FROM AUTHOR]

This paper provides a first example of a model theoretically well-behaved structure consisting of a proper o-minimal expansion of the real field and a dense multiplicative subgroup of finite rank. Under certain Schanuel conditions, a quantifier elimination result will be shown for the real field with an irrational power function xτ and a dense multiplicative subgroup of finite rank whose elements are algebraic over ℚ(τ). Moreover, every open set definable in this structure is already definable in the reduct given by just the real field and the irrational power function. [ABSTRACT FROM AUTHOR]

We extend the edit operators of substitution, deletion, and insertion of a symbol over a word by introducing two new operators (partial copy and partial elimination) inspired by biological gene duplication. We define a disruption measure for an operator over a word and prove that whereas the traditional edit operators are disruptive, partial copy and partial elimination are non-disruptive. Moreover, we show that the application of only edit operators does not generate (with low disruption) all the words over a binary alphabet, but this can indeed be done by combining partial copy and partial elimination with the substitution operator. [ABSTRACT FROM AUTHOR]

Is is shown that the inhabitation problem is decidable for intersection type assignment without the intersection elimination rule. [ABSTRACT FROM AUTHOR]

The classical inexact Newton algorithm is all efficient and popular technique for solving large sparse nonlinear systems of equations. When the nonlinearities in the system are well balanced, a near quadratic convergence is often observed; however, if some of the equations are ranch more nonlinear than the others in the system, the convergence is much slower. The slow convergence (or sometimes divergence) is often determined by the small number of equations in the system with the highest nonlinearities. The idea of nonlinear preconditioning has been proven to be very useful. Through subspace nonlinear solves, the local high nonlinearities are removed, and the fast convergence can then be restored when the inexact Newton algorithm is called after the preconditioning. Recently a left preconditioned inexact Newton method was proposed in which the nonlinear function is replaced by a preconditioned function with more balanced nonlinearities. In this paper, we combine an inexact Newton method with a restricted additive Schwarz based nonlinear elimination. The new approach is easier to implement than the left preconditioned method since the nonlinear function does not have to be replaced, and, furthermore, the nonlinear elimination step does not have to be called at every outer Newton iteration. We show numerically that it perform well for, as an example, solving the incompressible Navier-Stokes equations with high Reynolds numbers and on machines with large numbers of processors. [ABSTRACT FROM AUTHOR]

In order for the value structure of a given culture to be established, a number of its constituents have to be pushed beyond its boundary by shaping an abhorring figure of its Other. The exteriorization of such a figure is a necessary operation of any identity formation. According to Foucault, this entails a steady re-introduction of the delimited exterior into each interior instance of established identity. Not one of the identified instances remains ultimately spared of the rift caused by the necessity of founding elimination, although each of them tries to relegate it into oblivion. Foucault′s ethics resists such oblivion insisting upon the non-relation to alterity as the condition of possibility of relation to other human beings. The paper follows the further development of this ethics in the work of Maurice Blanchot, Jean-Luc Nancy and Giorgio Agamben. All of them highlight the constitutive priority of distance over proximity advocating therefore an eternal deferral of all established identities. In the conclusion an attempt is made to trace the genealogy of this ethical stance. [ABSTRACT FROM AUTHOR]

We show that, for arbitrary quantum feedback networks consisting of several quantum mechanical components connected by quantum fields, the limit of adiabatic elimination of fast oscillator modes in the components and the limit of instantaneous transmission along internal quantum field connections commute. The underlying technique is to show that both limits involve a Schur complement procedure. The result shows that the frequently used approximations, for instance, to eliminate strongly coupled optical cavities, are mathematically consistent. [ABSTRACT FROM AUTHOR]

Recently, Liu and Wang [Q. Liu and M. Wang, Algebraic properties and perturbation results for the indefinite least squares problem with equality constraints, Int. J. Comp. Math. 87(2) (2010), pp. 425-434.] proved that the solution of the equality constrained indefinite least squares (ILSE) problem min Bx=d(b-Ax)TJ(b-Ax), J=diag(-Iq, Ip) is the limit of the solution of the unconstrained weighted indefinite least squares (WILS) problem [image omitted] and J˜=diag(Is, J) as the weight μ tends to infinity, assuming that B has full row rank and xTATJAx>0 for all nonzero x∈null (B). Based on this observation, we derive a type of elimination method by applying the hyperbolic QR factorization method to above WILS problem and taking the limit analytically. Theoretical analysis shows that the method obtained is forward stable under a reasonable assumption. We illustrate our results with numerical tests. [ABSTRACT FROM AUTHOR]

The paper gives the numerical stencil for the two-dimensional convection diffusion equation and the technique of elimination, and builds up the new iterative scheme to solve the implicit difference equation. The scheme's convergence and its higher rate of convergence than the Jacobi iteration are proved. And the numerical example indicates that the new scheme has the same parallelism and a higher rate of convergence than the Jacobi iteration. [ABSTRACT FROM AUTHOR]

A function f: V→{-1,+1}, defined on the vertices of a graph G, is a signed clique-transversal function (SCTF) if ∑u∈V(C)f(u)≥1 for every clique C of G. The weight of an SCTF is w(f)=∑v∈V(G)f(v). The signed clique-transversal number, denoted [image omitted] , is the minimum weight of an SCTF of G. The signed clique-transversal problem is to find an SCTF of minimum weight for G. In this paper, we establish a tight lower bound on the signed clique-transversal number for a regular graph with clique number at most 4. Furthermore, we show that the decision problem corresponding to the problem of computing [image omitted] is NP-complete even when restricted to doubly chordal graphs. Also, we prove that the signed clique-transversal problem can be solved in linear time for a strongly chordal graph if its strong elimination ordering is given. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, two formulations for the Min-degree Constrained Minimum Spanning Tree Problem, one based on undirected Subtour Elimination Constraints and the other on Directed Cutset inequalities, are discussed. The quality of the Linear Programming bounds provided by them is addressed and a Branch-and-cut algorithm based on the strongest is investigated. Our computational experiments indicate that the method compares favorably with other exact and heuristic approaches in the literature, in terms of solution quality and execution times. Several new optimality certificates and new best upper bounds are provided here. [ABSTRACT FROM AUTHOR]

Abstract: The Steiner Tree Problem with Delays (STPD) is a variant of the well-known Steiner Tree Problem in which the delay on each path between a source node and a terminal node is limited by a given maximum value. We propose a Branch-and-Cut algorithm for solving this problem using a formulation based on lifted Miller-Tucker-Zemlin subtour elimination constraints. The effectiveness of the proposed algorithm is assessed through computational experiments carried out on dense benchmark instances. [ABSTRACT FROM AUTHOR]

To solve tridiagonal systems of linear equations, the Thomas Algorithm is a much more efficient method than, for instance, Gaussian elimination. The algorithm uses a series of elementary row operations and can solve a system of n equations in 𝒪( n) operations, instead of 𝒪( n3) . Many variations of the Thomas Algorithm have been developed over the years to solve very specific near-tridiagonal matrix. However, none of these methods address the situation of a system of linear equations that could easily be solved if elementary operations on columns are applied, instead of elementary operations on rows. The present paper proposes an efficient method that allows the use of elementary column operations to solve linear systems of equations using vector multiplication techniques, such as the one proposed by Thomas. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Single elimination tournaments are used as a context for illustrating some basic probability concepts. An algorithm which automatically constructs a tournament, given team seeding, is presented. Probabilities of winning are calculated as a function of team seed and strength, both of which are selected by the user. This technique allows for easy experimentation to see how the interaction of seeding and strength affects probabilities of winning. Users may also select a particular team to win up to a predetermined round in order to see the resulting changes in probabilities. Some examples with surprising results are used to illustrate how probabilities can change. [ABSTRACT FROM AUTHOR]

Abstract: A study was initiated to establish the suitability of the macroalgae, Catenella nipae as an environmental surveillance monitor for radiopharmaceutical waste discharges to aquatic environments. A series of experiments were conducted to establish the radioactive iodine (131I) concentration factor, and uptake and depuration characteristics of C. nipae. The steady state concentration factor was estimated to be 630±80mLg−1, with an uptake half-time of 160±20min. Elimination of 131I was found to follow a two phase model, the first having a rapid elimination rate with a half-time of <1min, followed by the second phase with a half-time of 3.2days. Application of the Michaelis–Menton model allowed calculation of an estimate for activity concentration of 131I in environmental waters from C. nipae sampling devices in the Brisbane River estuary, Australia. The results suggest that C. nipae may be used as an environmental radioactive waste sentinel. [Copyright &y& Elsevier]

Patterns of genetic diversity between populations are often used to detect loci under selection in genome scans. Indeed, loci involved in local adaptations should show high FST values, whereas loci under balancing selection should rather show low FST values. Most tests of selection based on FST use a null distribution generated under a simple island model of population differentiation. Although this model has been shown to be robust, many species have a more complex genetic structure, with some populations sharing a recent ancestry or due to the presence of barriers to gene flow between different parts of a species range. In this paper, we propose the use of a hierarchical island model, in which demes exchange more migrants within groups than between groups, to generate the joint distribution of genetic diversity within and between populations. We show that tests not accounting for a hierarchical structure, when it exists, do generate a large excess of false positive loci, whereas the hierarchical island model is robust to uncertainties about the exact number of groups and demes per group in the system. Our approach also explicitly takes into account the mutational process, and does not just rely on allele frequencies, which is important for short tandem repeat (STR) data. An application to human and stickleback STR data sets reveals a much lower number of significant loci than previously obtained under a non-hierarchical model. The elimination of false positive loci from genome scans should allow us to better determine on which specific class of genes selection is operating. [ABSTRACT FROM AUTHOR]

The article presents a study on two due window scheduling problems in a two-machine flow shop. Several dominance properties are derived such as elimination and sequencing rules and lower penalty bounds. It showed that the problems have nonregular performance measures due to lack of optimality results and solution techniques. Pseudopolynomial dynamic programming algorithms for solving the problems were then developed as a result.

Abstract: Harmonic elimination problem in PWM inverter is treated as an optimization problem and solved using particle swarm optimization (PSO) technique. The derived equation for computation of total harmonic distortion (THD) of the output voltage of PWM inverter is used as the objective function in the PSO algorithm. The objective function is minimized to contribute the minimum THD in the voltage waveform and the corresponding switching angles are computed. The method is applied to investigate the switching patterns of both unipolar and bipolar case. While minimizing the objective function, the individual selected harmonics like 5th, 7th, 11th and 13th can be controlled within the allowable limits by incorporating the constraints in the PSO algorithm. The results of the unipolar case using five switching angles are compared with that of a recently reported work and it is observed that the proposed method is effective in reducing the voltage THD in a wide range of modulation index. The simulated results are also validated through suitable experiments. [Copyright &y& Elsevier]

The article provides information on the establishment of correct connectivity between neurons and target cells. He notes of the remodeling of axons and connections which are needed for a precise neural connectivity. He mentions that neurons formulate exuberant axonal and dendritic processes which should undergo selective elimination to form mature neural circuits. He investigates on the cellular and molecular players of neural debris clearance.

There are two distinct approaches to the study of initial value problem of the periodic box-ball systems. One way is the rigged configuration approach due to Kuniba–Takagi–Takenouchi and another way is the 10-elimination approach due to Mada–Idzumi–Tokihiro. In this paper, we describe precisely interrelations between these two approaches. [ABSTRACT FROM AUTHOR]

Abstract: We introduced here an interesting tool for the structural study of chordal graphs, namely the Reduced Clique Graph. Using some of its combinatorial properties we show that for any chordal graph we can construct in linear time a simplicial elimination scheme starting with a pending maximal clique attached via a minimal separator maximal under inclusion among all minimal separators. [Copyright &y& Elsevier]

The aim of this article is Schröder's treatment of the so called solution problem [Auflösungsproblem]. First, I will introduce Schröder's ideas; then I will discuss them taking into account Peirce's considerations in The Logic of Relatives ([13, pp. 161-217] now republished in [9, pp. 288-345]). [ABSTRACT FROM AUTHOR]

Using Lyapunov's direct method, a novel frequency-domain criterion for the elimination of limit cycles in a class of digital filters using single saturation nonlinearity is derived. The criterion turns out to be a generalization and improvement over an earlier criterion due to Kar and Singh. An example showing the effectiveness of the criterion is given. A graphical interpretation of a simplified version (involving one free parameter) of the criterion is discussed. [ABSTRACT FROM AUTHOR]