What makes a phase transition? Analysis of the random satisfiability problem
Zweig, K A; Vicsek, T; 10.1016/j.physa.2009.12.051
2010-01-01
In the last 30 years it was found that many combinatorial systems undergo phase transitions. One of the most important examples of these can be found among the random k-satisfiability problems (often referred to as k-SAT), asking whether there exists an assignment of Boolean values satisfying a Boolean formula composed of clauses with k random variables each. The random 3-SAT problem is reported to show various phase transitions at different critical values of the ratio of the number of clauses to the number of variables. The most famous of these occurs when the probability of finding a satisfiable instance suddenly drops from 1 to 0. This transition is associated with a rise in the hardness of the problem, but until now the correlation between any of the proposed phase transitions and the hardness is not totally clear. In this paper we will first show numerically that the number of solutions universally follows a lognormal distribution, thereby explaining the puzzling question of why the number of solutions ...
Order-to-chaos transition in the hardness of random Boolean satisfiability problems
Varga, Melinda; Sumi, Róbert; Toroczkai, Zoltán; Ercsey-Ravasz, Mária
2016-05-01
Transient chaos is a ubiquitous phenomenon characterizing the dynamics of phase-space trajectories evolving towards a steady-state attractor in physical systems as diverse as fluids, chemical reactions, and condensed matter systems. Here we show that transient chaos also appears in the dynamics of certain efficient algorithms searching for solutions of constraint satisfaction problems that include scheduling, circuit design, routing, database problems, and even Sudoku. In particular, we present a study of the emergence of hardness in Boolean satisfiability (k -SAT), a canonical class of constraint satisfaction problems, by using an analog deterministic algorithm based on a system of ordinary differential equations. Problem hardness is defined through the escape rate κ , an invariant measure of transient chaos of the dynamical system corresponding to the analog algorithm, and it expresses the rate at which the trajectory approaches a solution. We show that for a given density of constraints and fixed number of Boolean variables N , the hardness of formulas in random k -SAT ensembles has a wide variation, approximable by a lognormal distribution. We also show that when increasing the density of constraints α , hardness appears through a second-order phase transition at αχ in the random 3-SAT ensemble where dynamical trajectories become transiently chaotic. A similar behavior is found in 4-SAT as well, however, such a transition does not occur for 2-SAT. This behavior also implies a novel type of transient chaos in which the escape rate has an exponential-algebraic dependence on the critical parameter κ ˜NB |α - αχ|1-γ with 0 <γ <1 . We demonstrate that the transition is generated by the appearance of metastable basins in the solution space as the density of constraints α is increased.
An optimization approach for the satisfiability problem
S. Noureddine
2015-01-01
Full Text Available We describe a new approach for solving the satisfiability problem by geometric programming. We focus on the theoretical background and give details of the algorithmic procedure. The algorithm is provably efficient as geometric programming is in essence a polynomial problem. The correctness of the algorithm is discussed. The version of the satisfiability problem we study is exact satisfiability with only positive variables, which is known to be NP-complete.
Clustering of solutions in hard satisfiability problems
Ardelius, John; Aurell, Erik; Krishnamurthy, Supriya
2007-10-01
We study numerically the solution space structure of random 3-SAT problems close to the SAT/UNSAT transition. This is done by considering chains of satisfiability problems, where clauses are added sequentially to a problem instance. Using the overlap measure of similarity between different solutions found on the same problem instance, we examine geometrical changes as a function of α. In each chain, the overlap distribution is first smooth, but then develops a tiered structure, indicating that the solutions are found in well separated clusters. On chains of not too large instances, all remaining solutions are eventually observed to be found in only one small cluster before vanishing. This condensation transition point is estimated by finite size scaling to be αc = 4.26 with an apparent critical exponent of about 1.7. The average overlap value is also observed to increase with α up to the transition, indicating a reduction in solutions space size, in accordance with theoretical predictions. The solutions are generated by a local heuristic, ASAT, and compared to those found by the Survey Propagation algorithm up to αc.
On Optimizing the Satisfiability (SAT) Problem
GU Jun; GU Qianping; DU Dingzhu
1999-01-01
The satisfiability(SAT) problem is abasic problem in computing theory. Presently, an active area of researchon SAT problem is to design efficient optimization algorithms forfinding a solution for a satisfiable CNF formula. A newformulation, the Universal SAT problem model, which transforms the SAT problem on Boolean space into an optimization problem on real spacehas been developed. Many optimization techniques,such as the steepest descent method, Newton's method, and thecoordinate descent method, can be used to solve the Universal SAT problem. In this paper, we prove that, when the initial solution issufficiently close to the optimal solution, the steepest descent methodhas a linear convergence ratio β<1, Newton's method has aconvergence ratio of order two, and the convergence ratio of thecoordinate descent method is approximately (1-β/m) for the Universal SAT problem with m variables. An algorithm based on the coordinate descent method for the Universal SAT problem is alsopresented in this paper.
On k-Positive Satisfiability Problem
HUANG Xiong; LI Wei
1999-01-01
An algorithm for solving thesatisfiability problem is presented. It is proved that this algorithmsolves 2-SAT and Horn-SAT in linear time and k-positive SAT(in which every clause contains at most k positive literals) in time, where |F| is the length of input F,n is the number of atoms occurring in F, and ξk is thegreatest real number satisfying the equation . Compared with previous results, this nontrivialupper bound on time complexity could only be obtained for k-SAT, whichis a subproblem of k-positive SAT.
Social balance as a satisfiability problem of computer science.
Radicchi, Filippo; Vilone, Daniele; Yoon, Sooeyon; Meyer-Ortmanns, Hildegard
2007-02-01
Reduction of frustration was the driving force in an approach to social balance as it was recently considered by Antal [T. Antal, P. L. Krapivsky, and S. Redner, Phys. Rev. E 72, 036121 (2005)]. We generalize their triad dynamics to k-cycle dynamics for arbitrary integer k. We derive the phase structure, determine the stationary solutions, and calculate the time it takes to reach a frozen state. The main difference in the phase structure as a function of k is related to k being even or odd. As a second generalization we dilute the all-to-all coupling as considered by Antal to a random network with connection probability w<1. Interestingly, this model can be mapped to a satisfiability problem of computer science. The phase of social balance in our original interpretation then becomes the phase of satisfaction of all logical clauses in the satisfiability problem. In common to the cases we study, the ideal solution without any frustration always exists, but the question actually is as to whether this solution can be found by means of a local stochastic algorithm within a finite time. The answer depends on the choice of parameters. After establishing the mapping between the two classes of models, we generalize the social-balance problem to a diluted network topology for which the satisfiability problem is usually studied. On the other hand, in connection with the satisfiability problem we generalize the random local algorithm to a p-random local algorithm, including a parameter p that corresponds to the propensity parameter in the social balance problem. The qualitative effect of the inclusion of this parameter is a bias towards the optimal solution and a reduction of the needed simulation time.
Exact satisfiability threshold for k -satisfiability problems on a Bethe lattice
Krishnamurthy, Supriya; Sumedha
2015-10-01
The satisfiability threshold for constraint satisfaction problems is that value of the ratio of constraints (or clauses) to variables, above which the probability that a random instance of the problem has a solution is zero in the large system limit. Two different approaches to obtaining this threshold have been discussed in the literature: using first or second moment methods which give rigorous bounds or using the nonrigorous but powerful replica-symmetry-breaking (RSB) approach, which gives very accurate predictions on random graphs. In this paper, we lay out a different route to obtaining this threshold on a Bethe lattice. We need make no assumptions about the solution-space structure, a key assumption in the RSB approach. Despite this, our expressions and threshold values exactly match the best predictions of the cavity method under the one-step RSB hypothesis. In addition we can use the same procedure to obtain other useful quantities on the Bethe lattice such as the second moment of the number of solutions. Our method hence provides alternate interpretations as well as motivations for the key equations in the RSB approach.
A mathematic-physical approach to the satisfiability problem
李未; 黄文奇
1995-01-01
A one-to-one and onto mapping between the set of conjunctive normal forms and a subset of the potential functions of static electric fields is given; it has been further proved that a conjunctive normal form is satisfiable if and only if there exists a zero point for its corresponding potential function. A particle is always moving in the direction of gradient descent in the field which is the fastest decreasing direction of potential of the particle. Thus, if a conjunctive normal form is satisfiable, the gradient method for its corresponding potential function becomes a fast algorithm to solve its satisfiability problem.
An Algorithm Based on Tabu Search for Satisfiability Problem
黄文奇; 张德富; 汪厚祥
2002-01-01
In this paper, a computationally effective algorithm based on tabu search for solving the satisfiability problem (TSSAT) is proposed. Some novel and efficient heuristic strategies for generating candidate neighborhood of the current assignment and selecting variables to be flipped are presented. Especially, the aspiration criterion and tabu list structure of TSSAT are different from those of traditional tabu search. Computational experiments on a class of problem instances show that, TSSAT, in a reasonable amount of computer time, yields better results than Novelty which is currently among the fastest known. Therefore, TSSAT is feasible and effective.
Formal Verification Techniques Based on Boolean Satisfiability Problem
Xiao-Wei Li; Guang-Hui Li; Ming Shao
2005-01-01
This paper exploits Boolean satisfiability problem in equivalence checking and model checking respectively. A combinational equivalence checking method based on incremental satisfiability is presented. This method chooses the can didate equivalent pairs with some new techniques, and uses incremental satisfiability algorithm to improve its performance. By substituting the internal equivalent pairs and converting the equivalence relations into conjunctive normal form (CNF) formulas, this approach can avoid the false negatives, and reduce the search space of SAT procedure. Experimental results on ISCAS'85 benchmark circuits show that, the presented approach is faster and more robust than those existed in literature.This paper also presents an algorithm for extracting of unsatisfiable core, which has an important application in abstraction and refinement for model checking to alleviate the state space explosion bottleneck. The error of approximate extraction is analyzed by means of simulation. An analysis reveals that an interesting phenomenon occurs, with the increasing density of the formula, the average error of the extraction is decreasing. An exact extraction approach for MU subformula, referred to as pre-assignment algorithm, is proposed. Both theoretical analysis and experimental results show that it is more efficient.
Numerical solution-space analysis of satisfiability problems
Mann, Alexander; Hartmann, A. K.
2010-11-01
The solution-space structure of the three-satisfiability problem (3-SAT) is studied as a function of the control parameter α (ratio of the number of clauses to the number of variables) using numerical simulations. For this purpose one has to sample the solution space with uniform weight. It is shown here that standard stochastic local-search (SLS) algorithms like average satisfiability (ASAT) exhibit a sampling bias, as does “Metropolis-coupled Markov chain Monte Carlo” (MCMCMC) (also known as “parallel tempering”) when run for feasible times. Nevertheless, unbiased samples of solutions can be obtained using the “ballistic-networking approach,” which is introduced here. It is a generalization of “ballistic search” methods and yields also a cluster structure of the solution space. As application, solutions of 3-SAT instances are generated using ASAT plus ballistic networking. The numerical results are compatible with a previous analytical prediction of a simple solution-space structure for small values of α and a transition to a clustered phase at αc≈3.86 , where the solution space breaks up into several non-negligible clusters. Furthermore, in the thermodynamic limit there are, even for α=4.25 close to the SAT-UNSAT transition αs≈4.267 , always clusters without any frozen variables. This may explain why some SLS algorithms are able to solve very large 3-SAT instances close to the SAT-UNSAT transition.
Satisfiability Parsimoniously Reduces to the Tantrix(TM) Rotation Puzzle Problem
Baumeister, Dorothea
2007-01-01
Holzer and Holzer (Discrete Applied Mathematics 144(3):345--358, 2004) proved that the Tantrix(TM) rotation puzzle problem is NP-complete. They also showed that for infinite rotation puzzles, this problem becomes undecidable. We study the counting version and the unique version of this problem. We prove that the satisfiability problem parsimoniously reduces to the Tantrix(TM) rotation puzzle problem. In particular, this reduction preserves the uniqueness of the solution, which implies that the unique Tantrix(TM) rotation puzzle problem is as hard as the unique satisfiability problem, and so is DP-complete under polynomial-time randomized reductions, where DP is the second level of the boolean hierarchy over NP.
THE CONSTRUCTION OF DENUMERABLE q-PROCESSES IN RANDOM ENVIRONMENTS SATISFYING (F) OR (B)
Hu Dihe; Hu Xiaoyu
2008-01-01
This article is a continuation of [9]. Based on the discussion of random Kol-mogorov forward (backward) equations, for any given q-matrix in random environment,Q(θ) = (q(θ; x, y), x, y ∈ X), an infinite class of q-processes in random environments sat-isfying the random Kolmogorov forward (backward) equation is constructed. Moreover,under some conditions, all the q-processes in random environments satisfying the random Kolmogorov forward (backward) equation are constructed.
Mandrà, Salvatore; Giacomo Guerreschi, Gian; Aspuru-Guzik, Alán
2016-07-01
We present an exact quantum algorithm for solving the Exact Satisfiability problem, which belongs to the important NP-complete complexity class. The algorithm is based on an intuitive approach that can be divided into two parts: the first step consists in the identification and efficient characterization of a restricted subspace that contains all the valid assignments of the Exact Satisfiability; while the second part performs a quantum search in such restricted subspace. The quantum algorithm can be used either to find a valid assignment (or to certify that no solution exists) or to count the total number of valid assignments. The query complexities for the worst-case are respectively bounded by O(\\sqrt{{2}n-{M\\prime }}) and O({2}n-{M\\prime }), where n is the number of variables and {M}\\prime the number of linearly independent clauses. Remarkably, the proposed quantum algorithm results to be faster than any known exact classical algorithm to solve dense formulas of Exact Satisfiability. As a concrete application, we provide the worst-case complexity for the Hamiltonian cycle problem obtained after mapping it to a suitable Occupation problem. Specifically, we show that the time complexity for the proposed quantum algorithm is bounded by O({2}n/4) for 3-regular undirected graphs, where n is the number of nodes. The same worst-case complexity holds for (3,3)-regular bipartite graphs. As a reference, the current best classical algorithm has a (worst-case) running time bounded by O({2}31n/96). Finally, when compared to heuristic techniques for Exact Satisfiability problems, the proposed quantum algorithm is faster than the classical WalkSAT and Adiabatic Quantum Optimization for random instances with a density of constraints close to the satisfiability threshold, the regime in which instances are typically the hardest to solve. The proposed quantum algorithm can be straightforwardly extended to the generalized version of the Exact Satisfiability known as Occupation
Quantum algorithms for biomolecular solutions of the satisfiability problem on a quantum machine.
Chang, Weng-Long; Ren, Ting-Ting; Luo, Jun; Feng, Mang; Guo, Minyi; Weicheng Lin, Kawuu
2008-09-01
In this paper, we demonstrate that the logic computation performed by the DNA-based algorithm for solving general cases of the satisfiability problem can be implemented more efficiently by our proposed quantum algorithm on the quantum machine proposed by Deutsch. To test our theory, we carry out a three-quantum bit nuclear magnetic resonance experiment for solving the simplest satisfiability problem.
Knuth, Donald E
2008-01-01
A special case of the satisfiability problem, in which the clauses have a hierarchical structure, is shown to be solvable in linear time, assuming that the clauses have been represented in a convenient way.
Finer Distinctions: Variability in Satisfied Older Couples' Problem-Solving Behaviors.
Rauer, Amy; Williams, Leah; Jensen, Jakob
2017-06-01
This study utilized observational and self-report data from 64 maritally satisfied and stable older couples to explore if there were meaningful differences in how couples approached marital disagreements. Using a typology approach to classify couples based on their behaviors in a 15-minute problem-solving interaction, findings revealed four types of couples: (1) problem solvers (characterized by both spouses' higher problem-solving skills and warmth), (2) supporters (characterized by both spouses' notable warmth), (3) even couples (characterized by both spouses' moderate problem-solving skills and warmth), and (4) cool couples (characterized by both spouses' greater negativity and lower problem-solving skills and warmth). Despite the differences in these behaviors, all couples had relatively high marital satisfaction and functioning. However, across nearly all indices, spouses in the cool couple cluster reported poorer marital functioning, particularly when compared to the problem solvers and supporters. These findings suggest that even modest doses of negativity (e.g., eye roll) may be problematic for some satisfied couples later in life. The implications of these typologies are discussed as they pertain to practitioners' efforts to tailor their approaches to a wider swath of the population. © 2015 Family Process Institute.
Random Field Satisfying a Linear Partial Differential Equation with Random Forcing Term.
1984-01-01
physical approximation 12 may be taken equal to 1. For k = 0, the experimental spectral density function of the random fluctuations of the pressure in deep...fa e , tlpt 2 in R , and the power spectral density function is 1 0 y(v) - 27 2 2’ y I a +v Proof: In that case da = X 0dT and r(tl,t2) =- e , the...power spectral density function of the solution X is V R___ 1 __ 2 I The second order properties are the same for every Poisson, Gaussian, Levy centered
Wang Yanxia; Qian Longjun; Guo Zhi; Ma Lifeng
2008-01-01
A weapon target assignment (WTA) model satisfying expected damage probabilities with an ant colony algorithm is proposed.In order to save armament resource and attack the targets effectively,the strategy of the weapon assignment is that the target with greater threat degree has higher priority to be intercepted.The effect of this WTA model is not maximizing the damage probability but satisfying the whole assignment result.Ant colony algorithm has been successfully used in many fields,especially in combination optimization.The ant colony algorithm for this WTA problem is described by analyzing path selection,pheromone update,and tabu table update.The effectiveness of the model and the algorithm is demonstrated with an example.
Hybrid genetic algorithm in the Hopfield network for maximum 2-satisfiability problem
Kasihmuddin, Mohd Shareduwan Mohd; Sathasivam, Saratha; Mansor, Mohd. Asyraf
2017-08-01
Heuristic method was designed for finding optimal solution more quickly compared to classical methods which are too complex to comprehend. In this study, a hybrid approach that utilizes Hopfield network and genetic algorithm in doing maximum 2-Satisfiability problem (MAX-2SAT) was proposed. Hopfield neural network was used to minimize logical inconsistency in interpretations of logic clauses or program. Genetic algorithm (GA) has pioneered the implementation of methods that exploit the idea of combination and reproduce a better solution. The simulation incorporated with and without genetic algorithm will be examined by using Microsoft Visual 2013 C++ Express software. The performance of both searching techniques in doing MAX-2SAT was evaluate based on global minima ratio, ratio of satisfied clause and computation time. The result obtained form the computer simulation demonstrates the effectiveness and acceleration features of genetic algorithm in doing MAX-2SAT in Hopfield network.
Warners, J.P.
1997-01-01
We show how a large class of combinatorial optimization problems can be reformulated as a nonconvex minimization problem over the unit hyper cube with continuous variables. No additional constraints are required; all constraints are incorporated in the n onconvex objective function, which is a polyn
Random eigenvalue problems revisited
S Adhikari
2006-08-01
The description of real-life engineering structural systems is associated with some amount of uncertainty in specifying material properties, geometric parameters, boundary conditions and applied loads. In the context of structural dynamics it is necessary to consider random eigenvalue problems in order to account for these uncertainties. Within the engineering literature, current methods to deal with such problems are dominated by approximate perturbation methods. Some exact methods to obtain joint distribution of the natural frequencies are reviewed and their applicability in the context of real-life engineering problems is discussed. A new approach based on an asymptotic approximation of multi-dimensional integrals is proposed. A closed-form expression for general order joint moments of arbitrary numbers of natural frequencies of linear stochastic systems is derived. The proposed method does not employ the ‘small randomness’ assumption usually used in perturbation based methods. Joint distributions of the natural frequencies are investigated using numerical examples and the results are compared with Monte Carlo simulation.
Penalty Formulations and Trap-Avoidance Strategies for Solving Hard Satisfiability Problems
Benjamin W. Wah; Zhe Wu
2005-01-01
In this paper we study the solution of SAT problems formulated as discrete decision and discrete constrained optimization problems. Constrained formulations are better than traditional unconstrained formulations because violated constraints may provide additional forces to lead a search towards a satisfiable assignment. We summarize the theory of extended saddle points in penalty formulations for solving discrete constrained optimization problems and the associated discrete penalty method (DPM). We then examine various formulations of the objective function, choices of neighborhood in DPM, strategies for updating penalties, and heuristics for avoiding traps. Experimental evaluations on hard benchmark instances pinpoint that traps contribute significantly to the inefficiency of DPM and force a trajectory to repeatedly visit the same set of or nearby points in the original variable space. To address this issue, we propose and study two trap-avoidance strategies. The first strategy adds extra penalties on unsatisfied clauses inside a trap, leading to very large penalties for unsatisfied clauses that are trapped more often and making these clauses more likely to be satisfied in the future. The second strategy stores information on points visited before, whether inside traps or not, and avoids visiting points that are close to points visited before. It can be implemented by modifying the penalty function in such a way that, if a trajectory gets close to points visited before, an extra penalty will take effect and force the trajectory to a new region. It specializes to the first strategy because traps are special cases of points visited before. Finally, we show experimental results on evaluating benchmarks in the DIMACS and SATLIB archives and compare our results with existing results on GSAT, WalkSAT, LSDL, and Grasp. The results demonstrate that DPM with trap avoidance is robust as well as effective for solving hard SAT problems.
Serna, Maria; Trevisan, Luca; Xhafa, Fatos
We present parallel approximation algorithms for maximization problems expressible by integer linear programs of a restricted syntactic form introduced by Barland et al. [BKT96]. One of our motivations was to show whether the approximation results in the framework of Barland et al. holds in the parallel setting. Our results are a confirmation of this, and thus we have a new common framework for both computational settings. Also, we prove almost tight non-approximability results, thus solving a main open question of Barland et al. We obtain the results through the constraint satisfaction problem over multi-valued domains, for which we show non-approximability results and develop parallel approximation algorithms. Our parallel approximation algorithms are based on linear programming and random rounding; they are better than previously known sequential algorithms. The non-approximability results are based on new recent progress in the fields of Probabilistically Checkable Proofs and Multi-Prover One-Round Proof Systems [Raz95, Hås97, AS97, RS97].
The Random Quadratic Assignment Problem
Paul, Gerald; Shao, Jia; Stanley, H. Eugene
2011-11-01
The quadratic assignment problem, QAP, is one of the most difficult of all combinatorial optimization problems. Here, we use an abbreviated application of the statistical mechanics replica method to study the asymptotic behavior of instances in which the entries of at least one of the two matrices that specify the problem are chosen from a random distribution P. Surprisingly, the QAP has not been studied before using the replica method despite the fact that the QAP was first proposed over 50 years ago and the replica method was developed over 30 years ago. We find simple forms for C min and C max , the costs of the minimal and maximum solutions respectively. Notable features of our results are the symmetry of the results for C min and C max and their dependence on P only through its mean and standard deviation, independent of the details of P.
Semenov, Alexander; Zaikin, Oleg
2016-01-01
In this paper we propose an approach for constructing partitionings of hard variants of the Boolean satisfiability problem (SAT). Such partitionings can be used for solving corresponding SAT instances in parallel. For the same SAT instance one can construct different partitionings, each of them is a set of simplified versions of the original SAT instance. The effectiveness of an arbitrary partitioning is determined by the total time of solving of all SAT instances from it. We suggest the approach, based on the Monte Carlo method, for estimating time of processing of an arbitrary partitioning. With each partitioning we associate a point in the special finite search space. The estimation of effectiveness of the particular partitioning is the value of predictive function in the corresponding point of this space. The problem of search for an effective partitioning can be formulated as a problem of optimization of the predictive function. We use metaheuristic algorithms (simulated annealing and tabu search) to move from point to point in the search space. In our computational experiments we found partitionings for SAT instances encoding problems of inversion of some cryptographic functions. Several of these SAT instances with realistic predicted solving time were successfully solved on a computing cluster and in the volunteer computing project SAT@home. The solving time agrees well with estimations obtained by the proposed method.
Finite-Size Scaling in Random K-SAT Problems
Ha, Meesoon; Lee, Sang Hoon; Jeon, Chanil; Jeong, Hawoong
2010-03-01
We propose a comprehensive view of threshold behaviors in random K-satisfiability (K-SAT) problems, in the context of the finite-size scaling (FSS) concept of nonequilibrium absorbing phase transitions using the average SAT (ASAT) algorithm. In particular, we focus on the value of the FSS exponent to characterize the SAT/UNSAT phase transition, which is still debatable. We also discuss the role of the noise (temperature-like) parameter in stochastic local heuristic search algorithms.
Mathematical Problems in Imaging in Random Media
2015-01-15
report our research results on the following topics: - Sound and electromagnetic wave propagation in random waveguides - Imaging in random waveguides...equation in the waveguide, with excitation given by a source with density ρ(~x) compactly supported around range z = 0, emitting a pulse f(t) with...in a time window of order ε−2ω−1o centered at τ , for an initial excitation in the q−th mode. It satisfies a linear system of transport equations, and
Random Walk Method for Potential Problems
Krishnamurthy, T.; Raju, I. S.
2002-01-01
A local Random Walk Method (RWM) for potential problems governed by Lapalace's and Paragon's equations is developed for two- and three-dimensional problems. The RWM is implemented and demonstrated in a multiprocessor parallel environment on a Beowulf cluster of computers. A speed gain of 16 is achieved as the number of processors is increased from 1 to 23.
Excited random walks: results, methods, open problems
Kosygina, Elena
2012-01-01
We consider a class of self-interacting random walks in deterministic or random environments, known as excited random walks or cookie walks, on the d-dimensional integer lattice. The main purpose of this paper is two-fold: to give a survey of known results and some of the methods and to present several new results. The latter include functional limit theorems for transient one-dimensional excited random walks in bounded i.i.d. cookie environments as well as some zero-one laws. Several open problems are stated.
Portfolio optimization and the random magnet problem
Rosenow, B.; Plerou, V.; Gopikrishnan, P.; Stanley, H. E.
2002-08-01
Diversification of an investment into independently fluctuating assets reduces its risk. In reality, movements of assets are mutually correlated and therefore knowledge of cross-correlations among asset price movements are of great importance. Our results support the possibility that the problem of finding an investment in stocks which exposes invested funds to a minimum level of risk is analogous to the problem of finding the magnetization of a random magnet. The interactions for this "random magnet problem" are given by the cross-correlation matrix C of stock returns. We find that random matrix theory allows us to make an estimate for C which outperforms the standard estimate in terms of constructing an investment which carries a minimum level of risk.
Bounded Satisfiability for PCTL
Bertrand, Nathalie; Schewe, Sven
2012-01-01
While model checking PCTL for Markov chains is decidable in polynomial-time, the decidability of PCTL satisfiability, as well as its finite model property, are long standing open problems. While general satisfiability is an intriguing challenge from a purely theoretical point of view, we argue that general solutions would not be of interest to practitioners: such solutions could be too big to be implementable or even infinite. Inspired by bounded synthesis techniques, we turn to the more applied problem of seeking models of a bounded size: we restrict our search to implementable -- and therefore reasonably simple -- models. We propose a procedure to decide whether or not a given PCTL formula has an implementable model by reducing it to an SMT problem. We have implemented our techniques and found that they can be applied to the practical problem of sanity checking -- a procedure that allows a system designer to check whether their formula has an unexpectedly small model.
Large Deviations for Random Matricial Moment Problems
Nagel, Jan; Gamboa, Fabrice; Rouault, Alain
2010-01-01
We consider the moment space $\\mathcal{M}_n^{K}$ corresponding to $p \\times p$ complex matrix measures defined on $K$ ($K=[0,1]$ or $K=\\D$). We endow this set with the uniform law. We are mainly interested in large deviations principles (LDP) when $n \\rightarrow \\infty$. First we fix an integer $k$ and study the vector of the first $k$ components of a random element of $\\mathcal{M}_n^{K}$. We obtain a LDP in the set of $k$-arrays of $p\\times p$ matrices. Then we lift a random element of $\\mathcal{M}_n^{K}$ into a random measure and prove a LDP at the level of random measures. We end with a LDP on Carth\\'eodory and Schur random functions. These last functions are well connected to the above random measure. In all these problems, we take advantage of the so-called canonical moments technique by introducing new (matricial) random variables that are independent and have explicit distributions.
Cliques, coloring, and satisfiability
Johnson, David S
1996-01-01
The purpose of a DIMACS Challenge is to encourage and coordinate research in the experimental analysis of algorithms. The First DIMACS Challenge encouraged experimental work in the area of network flow and matchings. The Second DIMACS Challenge, on which this volume is based, took place in conjunction with the DIMACS Special Year on Combinatorial Optimization. Addressed here are three difficult combinatorial optimization problems: finding cliques in a graph, coloring the vertices of a graph, and solving instances of the satisfiability problem. These problems were chosen both for their practical interest and because of their theoretical intractability.
SATISFIABILITY METHODS FOR COLOURING GRAPHS
Munmun Dey
2013-02-01
Full Text Available The graph colouring problem can be solved using methods based on Satisfiability (SAT. An instance of the problem is defined by a Boolean expression written using Boolean variables and the logical connectives AND, OR and NOT. It has to be determined whether there is an assignment of TRUE and FALSE values to the variables that makes the entire expression true.A SAT problem is syntactically and semantically quite simple. Many Constraint Satisfaction Problems (CSPsin AI and OR can be formulated in SAT. These make use of two kinds of searchalgorithms: Deterministic and Randomized.It has been found that deterministic methods when run on hard CSP instances are frequently very slow in execution.A deterministic method always outputs a solution in the end, but it can take an enormous amount of time to do so.This has led to the development of randomized search algorithms like GSAT, which are typically based on local (i.e., neighbourhood search. Such methodshave been applied very successfully to find good solutions to hard decision problems
Fault Tolerant Boolean Satisfiability
Roy, A
2011-01-01
A delta-model is a satisfying assignment of a Boolean formula for which any small alteration, such as a single bit flip, can be repaired by flips to some small number of other bits, yielding a new satisfying assignment. These satisfying assignments represent robust solutions to optimization problems (e.g., scheduling) where it is possible to recover from unforeseen events (e.g., a resource becoming unavailable). The concept of delta-models was introduced by Ginsberg, Parkes and Roy (AAAI 1998), where it was proved that finding delta-models for general Boolean formulas is NP-complete. In this paper, we extend that result by studying the complexity of finding delta-models for classes of Boolean formulas which are known to have polynomial time satisfiability solvers. In particular, we examine 2-SAT, Horn-SAT, Affine-SAT, dual-Horn-SAT, 0-valid and 1-valid SAT. We see a wide variation in the complexity of finding delta-models, e.g., while 2-SAT and Affine-SAT have polynomial time tests for delta-models, testing w...
On Optimal Harvesting Problems in Random Environments
Song, Qingshuo; Zhu, Chao
2010-01-01
This paper investigates the optimal harvesting strategy for a single species living in random environments, whose growth is given by a regime-switching diffusion. Harvesting is introduced as a stochastic control. The objective is to find a harvesting strategy which maximizes the expected total discounted income from harvesting up to extinction. This is a singular stochastic control problem, with both the extinction time and harvesting policy depending on the initial condition. Consequently one no longer obtains continuity of the value function for free using the standard arguments as those in regular or singular stochastic control problems. This paper provides a sufficient condition under which the continuity of the value function is obtained. Further, we show that the value function is a viscosity solution of a coupled system of quasi-variational inequalities. A verification theorem is also established. Based upon the verification theorem, we explicitly construct an $\\varepsilon$-optimal harvesting strategy ...
Introduction to mathematics of satisfiability
Marek, Victor W
2009-01-01
Although this area has a history of over 80 years, it was not until the creation of efficient SAT solvers in the mid-1990s that it became practically important, finding applications in electronic design automation, hardware and software verification, combinatorial optimization, and more. Exploring the theoretical and practical aspects of satisfiability, Introduction to Mathematics of Satisfiability focuses on the satisfiability of theories consisting of propositional logic formulas. It describes how SAT solvers and techniques are applied to problems in mathematics and computer science as well
Mathematical conversations multicolor problems, problems in the theory of numbers, and random walks
Dynkin, E B
2006-01-01
Comprises Multicolor Problems, dealing with map-coloring problems; Problems in the Theory of Numbers, an elementary introduction to algebraic number theory; Random Walks, addressing basic problems in probability theory. 1963 edition.
da Luz, Marcos G. E.; Grosberg, Alexander; Raposo, Ernesto P.; Viswanathan, Gandhi M.
2009-10-01
`I can't find my keys!' Who hasn't gone through this experience when leaving, in a hurry, to attend to some urgent matter? The keys could be in many different places. Unless one remembers where he or she has left the keys, the only solution is to look around, more or less randomly. Random searches are common because in many cases the locations of the specific targets are not known a priori. Indeed, such problems have been discussed in diverse contexts, attracting the interest of scientists from many fields, for example: the dynamical or stochastic search for a stable minimum in a complex energy landscape, relevant to systems such as glasses, protein (folding), and others; oil recovery from mature reservoirs; proteins searching for their specific target sites on DNA; animal foraging; survival at the edge of extinction due to low availability of energetic resources; automated searches of registers in high-capacity databases, search engine (e.g., `crawlers') that explore the internet; and even pizza delivery in a jammed traffic system of a medium-size town. In this way, the subject is interesting, challenging and has recently become an important scientific area of investigation. Although the applications are diverse, the underlying physical mechanisms are the same which will become clear in this special issue. Moreover, the inherent complexity of the problem, the abundance of ideas and methods found in this growing interdisciplinary field of research is studied in many areas of physics. In particular, the concepts and methods of statistical mechanics are particularly useful to the study of random searches. On one hand, it centres on how to find the global or local maxima of search efficiency functions with incomplete information. This is, of course, related to the long tradition in physics of using different conceptual and mathematical tools, such as variational methods, to extremize relevant quantities, e.g., energy, entropy and action. Such ideas and approaches are
Satisfiability with Index Dependency
Hong-Yu Liang; Jing He
2012-01-01
We study the Boolean satisfiability problem (SAT) restricted on input formulas for which there are linear arithmetic constraints imposed on the indices of variables occurring in the same clause.This can be seen as a structural counterpart of Schaefer's dichotomy theorem which studies the SAT problem with additional constraints on the assigned values of variables in the same clause.More precisely,let k-SAT(m,A) denote the SAT problem restricted on instances of k-CNF formulas,in every clause of which the indices of the last k-m variables are totally decided by the first m ones through some linear equations chosen from A.For example,if A contains i3 =i1+2i2 and i4 =i2-i1 + 1,then a clause of the input to 4-SAT(2,A) has the form yi1∨yi2∨yi1+2i2∨yi2-i1+1,with yi being xi or (xi).We obtain the following results:1) If m ≥2,then for any set A of linear constraints,the restricted problem k-SAT(m,A) is either in P or NP-complete assuming P ≠ NP.Moreover,the corresponding #SAT problem is always #P-complete,and the MAx-SAT problem does not allow a polynomial time approximation scheme assuming P ≠ NP.2) m =1,that is,in every clause only one index can be chosen freely.In this case,we develop a general framework together with some techniques for designing polynomial-time algorithms for the restricted SAT problems.Using these,we prove that for any A,#2-SAT(1,A) and MAX-2-SAT(1,A) are both polynomial-time solvable,which is in sharp contrast with the hardness results of general #2-SAT and MAX-2-SAT.For fixed k≥ 3,we obtain a large class of non-trivial constraints A,under which the problems k-SAT(1,A),#k-SAT(1,A)and MAx-k-SAT(1,A) can all be solved in polynomial time or quasi-polynomial time.
The backtracking survey propagation algorithm for solving random K-SAT problems
Marino, Raffaele; Parisi, Giorgio; Ricci-Tersenghi, Federico
2016-10-01
Discrete combinatorial optimization has a central role in many scientific disciplines, however, for hard problems we lack linear time algorithms that would allow us to solve very large instances. Moreover, it is still unclear what are the key features that make a discrete combinatorial optimization problem hard to solve. Here we study random K-satisfiability problems with K=3,4, which are known to be very hard close to the SAT-UNSAT threshold, where problems stop having solutions. We show that the backtracking survey propagation algorithm, in a time practically linear in the problem size, is able to find solutions very close to the threshold, in a region unreachable by any other algorithm. All solutions found have no frozen variables, thus supporting the conjecture that only unfrozen solutions can be found in linear time, and that a problem becomes impossible to solve in linear time when all solutions contain frozen variables.
DNA自组装的可满足性问题模型%DNA Self-assembly Model for General Satisfiability Problem
宋勃升; 殷志祥; 甄诚; 华程
2011-01-01
DNA self-assembly technology has played an important role in the field of DNA computing and nanotechnology. Many NP complete problems can be solved by self-assembly model. In this paper, we take the general satisfiability problem as a model, construction the special form of supplement chain with variable in normal form, hybridization with the them, So it can form hairpin structure, since the DNA chain with hairpin and the DNA chains with no-hairpin structure can have different length, we can extracted these chains with hairpin by gel electrophoresis; then add up these special chain's fully complementary DNA chains, at a certain temperature, according to Watson-Crick principle, hairpin structure would be re-opened. The model makes full use of DNA molecules self-assembly capability, we only need to use gel electrophoresis operation in the calculation, it can greatly reduces of experimental error caused by the excessive operation.%DNA自组装技术在DNA计算和纳米技术领域都发挥着极其重要的作用,许多小规模NP完全问题都可以通过自组装模型得以解决.文中以可满足问题为模型,通过构造范式中变量的特殊补链,使其与初始数据库中初始DNA链发生杂交反应,形成发夹结构,利用形成发夹结构的DNA链与没形成发夹结构的DNA链长度不同的特点,通过凝胶电泳将这些带发夹的DNA链提取出来；然后加入与这些特殊补链完全互补的DNA链,在一定温度下,通过碱基互补配对原则,发夹结构又将被重新打开.该模型充分利用了DNA分子间的自组装能力,在计算过程中只需要用到凝胶电泳操作,在一定程度上大大减少了因生物操作过多而引起的各种实验误差.
Molecular Beacon Based DNA Computing Model for General Satisfiability Problem%可满足问题的分子信标计算模型
殷志祥; 崔建中; 支凌迎; 孙侠; 黄晓慧
2008-01-01
分子信标(Molecular Beacon)是一种发夹状的荧光探针,它可以特异地和那些与分子信标的环(Loop)互补的核酸靶序列杂交,具有单个碱基错配的检测能力.肽核酸(Peptide Nucleic Acid)是人工合成的核酸(DNA)的类似物.PNA骨架为酰胺键,与DNA补链杂交更稳定,可以阻止聚合酶延伸反应.文中将可满足问题的约束变量编码于分子信标的环部识别区,通过分子信标与使得给定范式为真的变量的PNA补链杂交,再利用PNA链可以阻止聚合酶延伸反应的性质,用限制性内切酶EcoRI降解对应于非解的分子信标,最后通过加热表面使分子信标构形发生变化,产生荧光读解.提出的可满足问题的分子信标计算模型具有可靠性高、无需观察和记录计算的中间结果、读解简单等优点.%Molecular Beacon is a hairpin-shaped fluorescent probe,which can hybridize with great specificity target sequence that is complement to its loop sequence.The specificity of Molec-ular Beacon is as high as single base mismatch detection.Peptide Nucleic Acid (PNA) is an artifi-cial synthesized analogue of nature occurring DNA,in which the DNA sugar-phosphate backbone has been replaced by a pseudo-peptide.Thus the hybridization of PNA to complement DNA strand is more specific and stable than that of DNA to DNA.PNA can stop polymerase extension reaction as well.In this paper,Molecular Beacons were employed to encode variables in satisfi-ability problem and complement PNA strands were added and allowed to hybridize with Molecular Beacon.The hybridized PNA strands on Molecular Beacon stopped polymerase extension reac-tion,causing Molecular Beacon corresponding to non-solution were digested by means of restric-tion endonuclease EcoRI.The remaining Molecular Beacons encoding solutions were read out via heating.The appealing characteristics of proposed method in this paper are: Reliable,no obser-vation and record of midst solution,easy solution detection.
Generalizing Boolean Satisfiability III: Implementation
Dixon, H E; Hofer, D; Luks, E M; Parkes, A J; 10.1613/jair.1656
2011-01-01
This is the third of three papers describing ZAP, a satisfiability engine that substantially generalizes existing tools while retaining the performance characteristics of modern high-performance solvers. The fundamental idea underlying ZAP is that many problems passed to such engines contain rich internal structure that is obscured by the Boolean representation used; our goal has been to define a representation in which this structure is apparent and can be exploited to improve computational performance. The first paper surveyed existing work that (knowingly or not) exploited problem structure to improve the performance of satisfiability engines, and the second paper showed that this structure could be understood in terms of groups of permutations acting on individual clauses in any particular Boolean theory. We conclude the series by discussing the techniques needed to implement our ideas, and by reporting on their performance on a variety of problem instances.
Random Group Problem-Based Learning in Engineering Dynamics
Fleischfresser, Luciano
2014-01-01
Dynamics problem solving is highly specific to the problem at hand and to develop the general mind framework to become an effective problem solver requires ingenuity and creativity on top of a solid grounding on theoretical and conceptual knowledge. A blended approach with prototype demo, problem-based learning, and an opinion questionnaire was used during first semester of 2013. Students working in randomly selected teams had to interact with classmates while solving a randomly selected problem. The approach helps improve awareness of what is important to learn in this class while reducing grading load. It also provides a more rewarding contact time for both pupils and instructor.
IMPROVED RANDOMIZED ALGORITHM FOR THE EQUIVALENT 2-CATALOG SEGMENTATION PROBLEM
无
2005-01-01
An improved randomized algorithm of the equivalent 2-catalog segmentation problem is presented. The result obtained in this paper makes some progress to answer the open problem by analyze this algorithm with performance guarantee. A 0.6378-approximation for the equivalent 2-catalog segmentation problem is obtained.
Terminal Satisfiability in GSTE
Yongsheng Xu
2014-01-01
Full Text Available Generalized symbolic trajectory evaluation (GSTE is an extension of symbolic trajectory evaluation (STE and a method of model checking. GSTE specifications are given as assertion graphs. There are four efficient methods to verify whether a circuit model obeys an assertion graph in GSTE, Model Checking Strong Satisfiability (SMC, Model Checking Normal Satisfiability (NMC, Model Checking Fair Satisfiability (FMC, and Model Checking Terminal Satisfiability (TMC. SMC, NMC, and FMC have been proved and applied in industry, but TMC has not. This paper gives a six-tuple definition and presents a new algorithm for TMC. Based on these, we prove that our algorithm is sound and complete. It solves the SMC’s limitation (resulting in false negative without extending from finite specification to infinite specification. At last, a case of using TMC to verify a realistic hardware circuit round-robin arbiter is achieved. Avoiding verifying the undesired paths which are not related to the specifications, TMC makes it possible to reduce the computational complexity, and the experimental results suggest that the time cost by SMC is 3.14× with TMC in the case.
Keeping the Customer Satisfied.
Coll, Richard K.; Eames, Chris; Halsey, Elizabeth
1997-01-01
A survey of 111 cooperative education students in New Zealand found only 45% satisfied with their supervisors; 90% felt the placement helped with career choice; 70% wanted more help with report writing. Better methods of supervision and student assessment were devised. (SK)
咸爱勇; 朱大铭
2015-01-01
合取范式可满足与最大可满足问题是理论计算机科学的核心问题．最大不全满足问题是最大可满足问题的一般化．限制每个子句均含有 k（2）个字母的最大不全满足问题又称为最大不全 k 满足问题．最大不全满足问题的算法进展，以解答该类问题的半定规划松弛法最具代表性．关于最大不全2满足、3满足和4满足问题，目前性能最好的近似算法分别由Goemans 与 Williamson、Zwick、Karloff 与 Zwick 给出，近似性能比分别为1．139（1／0．878）、1．10047（1／0．9087）和8／7．当 k5时，最大不全 k 满足问题的近似算法则未曾见到．文中给出了一个解答最大不全k 满足问题的局部搜索算法，近似性能比可达到2k －1／（2k －1－1），k 2；进一步将该方法推广到解答由不少于 k 个字母的子句构成的最大不全k 满足问题，近似性能比亦可达到2k －1／（2k －1－1）．利用解答最大不全 k 满足问题的近似算法，给出了解答最大 k 可满足问题的新近似算法，近似性能比可达到2k／（2k －1）．文中最后证明了若 P≠NP，则 k4的最大不全 k 满足问题不能近似到小于2k －1／（2k －1－1），从而说明文中解答最大不全 k 满足问题的算法近似性能比是最优的．%The satisfiability problem as well as the maximum satisfiability problem of conjunctive norm forms are the central problems in theoretical computer science.The maximum not-all-equal satisfiability problem is a generalization of the maximum satisfiability problem.The maximum not-all-equal satisfiability problem is named maximum not-all-equal k satisfiability problem,if each clause of its instance contains k (2)literals.Semi-definite programming relaxation is the frequently-used also the most typical method for solving the maximum not-all-equal satisfiability problems.To our knowledge at present,the best algorithms for
A random search algorithm for cyclic delivery synchronization problem
Katarzyna Gdowska
2017-09-01
Full Text Available Background: The paper is devoted to the cyclic delivery synchronization problem with vehicles serving fixed routes. Each vehicle is assigned to a fixed route: the series of supplier’s and logistic centers to be visited one after another. For each route the service frequency is fixed and known in advance. A vehicle loads at a supplier’s, then it delivers goods to a logistic center and either loads other goods there and delivers them to the next logistic center along the route or goes to another logistic center. Each logistic center can belong to several routes, so goods are delivered there with one vehicle and then they departure for the further journey with another truck. The objective of this cyclic delivery synchronization problem is to maximize the total number of synchronizations of vehicles arrivals in logistic centers and their load times, so that it is possible to organize their arrivals in repeatable blocks. Methods: Basing on the previously developed mathematical model for the cyclic delivery synchronization problem we built a random search algorithm for cyclic delivery synchronization problem. The random heuristic search utilizes objective-oriented randomizing. In the paper the newly-developed random search algorithm for cyclic delivery synchronization problem is presented. Results: A computational experiment consisted of employing the newly-developed random search algorithm for solving a series of cyclic delivery synchronization problems. Results obtained with the algorithm were compared with solutions computed with the exact method. Conclusions: The newly-developed random search algorithm for cyclic delivery synchronization problem gives results which are considerably close to the ones obtained with mixed-integer programming. The main advantage of the algorithm is reduction of computing time; it is relevant for utilization of this method in practice, especially for large-sized problems.
Multipath Detection Using Boolean Satisfiability Techniques
Fadi A. Aloul
2011-01-01
Full Text Available A new technique for multipath detection in wideband mobile radio systems is presented. The proposed scheme is based on an intelligent search algorithm using Boolean Satisfiability (SAT techniques to search through the uncertainty region of the multipath delays. The SAT-based scheme utilizes the known structure of the transmitted wideband signal, for example, pseudo-random (PN code, to effectively search through the entire space by eliminating subspaces that do not contain a possible solution. The paper presents a framework for modeling the multipath detection problem as a SAT application. It also provides simulation results that demonstrate the effectiveness of the proposed scheme in detecting the multipath components in frequency-selective Rayleigh fading channels.
Random functions via Dyson Brownian Motion: progress and problems
Wang, Gaoyuan; Battefeld, Thorsten [Institute for Astrophysics, University of Goettingen,Friedrich Hund Platz 1, D-37077 Goettingen (Germany)
2016-09-05
We develope a computationally efficient extension of the Dyson Brownian Motion (DBM) algorithm to generate random function in C{sup 2} locally. We further explain that random functions generated via DBM show an unstable growth as the traversed distance increases. This feature restricts the use of such functions considerably if they are to be used to model globally defined ones. The latter is the case if one uses random functions to model landscapes in string theory. We provide a concrete example, based on a simple axionic potential often used in cosmology, to highlight this problem and also offer an ad hoc modification of DBM that suppresses this growth to some degree.
Random functions via Dyson Brownian Motion: progress and problems
Wang, Gaoyuan; Battefeld, Thorsten
2016-09-01
We develope a computationally efficient extension of the Dyson Brownian Motion (DBM) algorithm to generate random function in C2 locally. We further explain that random functions generated via DBM show an unstable growth as the traversed distance increases. This feature restricts the use of such functions considerably if they are to be used to model globally defined ones. The latter is the case if one uses random functions to model landscapes in string theory. We provide a concrete example, based on a simple axionic potential often used in cosmology, to highlight this problem and also offer an ad hoc modification of DBM that suppresses this growth to some degree.
Random Functions via Dyson Brownian Motion: Progress and Problems
Wang, Gaoyuan
2016-01-01
We develope a computationally efficient extension of the Dyson Brownian Motion (DBM) algorithm to generate random function in C2 locally. We further explain that random functions generated via DBM show an unstable growth as the traversed distance increases. This feature restricts the use of such functions considerably if they are to be used to model globally defined ones. The latter is the case if one used random functions to model landscapes in string theory. We provide a concrete example, based on a simple axionic potential often used in cosmology, to highlight this problem and also offer an ad hoc modification of DBM that suppresses this growth to some degree.
Boolean Satisfiability using Noise Based Logic
Lin, Pey-Chang Kent; Khatri, Sunil P
2011-01-01
In this paper, we present a novel algorithm to solve the Boolean Satisfiability (SAT) problem, using noise-based logic (NBL). Contrary to what the name may suggest, NBL is not a random/fuzzy logic system. In fact, it is a completely deterministic logic system. A key property of NBL is that it allows us to apply a superposition of many input vectors to a SAT instance at the same time, circumventing a key restriction and assumption in the traditional approach to solving SAT. By exploiting the superposition property of NBL, our NBL-based SAT algorithm can determine whether an instance is SAT or not in a single operation. A satisfying solution can be found by iteratively performing SAT check operations up to n times, where n is the number of variables in the SAT instance. Although this paper does not focus on the realization of an NBL-based SAT engine, such an engine can be conceived using analog circuits (wide-band amplifiers, adders and multipliers), FPGAs or ASICs. Additionally, we also discus scalability of o...
STOCHASTIC LINEAR QUADRATIC OPTIMAL CONTROL PROBLEMS WITH RANDOM COEFFICIENTS
无
2000-01-01
This paper studies a stochastic linear quadratic optimal control problem (LQ problem, for short), for which the coefficients are allowed to be random and the cost functional is allowed to have a negative weight on the square of the control variable. The authors introduce the stochastic Riccati equation for the LQ problem. This is a backward SDE with a complicated nonlinearity and a singularity. The local solvability of such a backward SDE is established, which by no means is obvious. For the case of deterministic coefficients, some further discussions on the Riccati equations have been carried out. Finally, an illustrative example is presented.
Generalizing Boolean Satisfiability II: Theory
Dixon, H E; Luks, E M; Parkes, A J; 10.1613/jair.1555
2011-01-01
This is the second of three planned papers describing ZAP, a satisfiability engine that substantially generalizes existing tools while retaining the performance characteristics of modern high performance solvers. The fundamental idea underlying ZAP is that many problems passed to such engines contain rich internal structure that is obscured by the Boolean representation used; our goal is to define a representation in which this structure is apparent and can easily be exploited to improve computational performance. This paper presents the theoretical basis for the ideas underlying ZAP, arguing that existing ideas in this area exploit a single, recurring structure in that multiple database axioms can be obtained by operating on a single axiom using a subgroup of the group of permutations on the literals in the problem. We argue that the group structure precisely captures the general structure at which earlier approaches hinted, and give numerous examples of its use. We go on to extend the Davis-Putnam-Logemann-...
Childs John D
2006-02-01
Full Text Available Abstract Background Recently a clinical prediction rule (CPR has been developed and validated that accurately identifies patients with low back pain (LBP that are likely to benefit from a lumbo-pelvic thrust manipulation. The studies that developed and validated the rule used the identical manipulation procedure. However, recent evidence suggests that different manual therapy techniques may result similar outcomes. The purpose of this study is to investigate the effectiveness of three different manual therapy techniques in a subgroup of patient with low back pain that satisfy the CPR. Methods/Design Consecutive patients with LBP referred to physical therapy clinics in one of four geographical locations who satisfy the CPR will be invited to participate in this randomized clinical trial. Subjects who agree to participate will undergo a standard evaluation and complete a number of patient self-report questionnaires including the Oswestry Disability Index (OSW, which will serve as the primary outcome measure. Following the baseline examination patients will be randomly assigned to receive the lumbopelvic manipulation used in the development of the CPR, an alternative lumbar manipulation technique, or non-thrust lumbar mobilization technique for the first 2 visits. Beginning on visit 3, all 3 groups will receive an identical standard exercise program for 3 visits (visits 3,4,5. Outcomes of interest will be captured by a therapist blind to group assignment at 1 week (3rd visit, 4 weeks (6th visit and at a 6-month follow-up. The primary aim of the study will be tested with analysis of variance (ANOVA using the change in OSW score from baseline to 4-weeks (OSWBaseline – OSW4-weeks as the dependent variable. The independent variable will be treatment with three levels (lumbo-pelvic manipulation, alternative lumbar manipulation, lumbar mobilization. Discussion This trial will be the first to investigate the effectiveness of various manual therapy
王芙; 周育人; 叶立
2012-01-01
布尔可满足性问题(Boolean Satisfiability Problem,SAT)是逻辑学的一个基本问题,也是NP-hard问题.调查传播算法(Survey Propagation,SP)是求解SAT的一种非常高效的算法,但SP在难解区域极易不收敛,或者出现错误赋值.将SP算法与蚁群算法结合,把SP算法得到的消息值应用到蚁群算法中来求解3-SAT问题,使用这些消息值引导蚁群算法求解,并在算法中加入高效的局部搜索.新算法对于SP算法不收敛的一些实例也能很快找到解.%Satisfiability problem is a basic problem in logic,and also is NP-hard. Survey propagation(SP) is a very effective algorithm for this problem. However, SP tends not to converge in hard region, or gives wrong assignments to the variables. An algorithm combined with SP and ant colony optimization(ACO) was proposed The messages calculated in SP were used in ACO as guidance to help ACO find a solution. And local search was conducted in the new algorithm. The new algorithm can quickly find solutions for some instances that SP doesn't work.
One-loop diagrams in the random Euclidean matching problem
Lucibello, Carlo; Parisi, Giorgio; Sicuro, Gabriele
2017-01-01
The matching problem is a notorious combinatorial optimization problem that has attracted for many years the attention of the statistical physics community. Here we analyze the Euclidean version of the problem, i.e., the optimal matching problem between points randomly distributed on a d -dimensional Euclidean space, where the cost to minimize depends on the points' pairwise distances. Using Mayer's cluster expansion we write a formal expression for the replicated action that is suitable for a saddle point computation. We give the diagrammatic rules for each term of the expansion, and we analyze in detail the one-loop diagrams. A characteristic feature of the theory, when diagrams are perturbatively computed around the mean field part of the action, is the vanishing of the mass at zero momentum. In the non-Euclidean case of uncorrelated costs instead, we predict and numerically verify an anomalous scaling for the sub-sub-leading correction to the asymptotic average cost.
Solving the wind farm layout optimization problem using random search algorithm
Feng, Ju; Shen, Wen Zhong
2015-01-01
is presented, which starts from an initial feasible layout and then improves the layout iteratively in the feasible solution space. It was first proposed in our previous study and improved in this study by adding some adaptive mechanisms. It can serve both as a refinement tool to improve an initial design......Wind farm (WF) layout optimization is to find the optimal positions of wind turbines (WTs) inside a WF, so as to maximize and/or minimize a single objective or multiple objectives, while satisfying certain constraints. In this work, a random search (RS) algorithm based on continuous formulation...... by expert guesses or other optimization methods, and as an optimization tool to find the optimal layout of WF with a certain number of WTs. A new strategy to evaluate layouts is also used, which can largely save the computation cost. This method is first applied to a widely studied ideal test problem...
Diffusion processes satisfying a conservation law constraint
Bakosi, J
2014-01-01
We investigate coupled stochastic differential equations governing N non-negative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires that a set of fluctuating variables be non-negative and (if appropriately normalized) sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the non-negativity and the unit-sum conservation law constraint are satisfied as the variables evolve in time. We investigate the consequences of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have di...
Randomized shortest-path problems: two related models.
Saerens, Marco; Achbany, Youssef; Fouss, François; Yen, Luh
2009-08-01
This letter addresses the problem of designing the transition probabilities of a finite Markov chain (the policy) in order to minimize the expected cost for reaching a destination node from a source node while maintaining a fixed level of entropy spread throughout the network (the exploration). It is motivated by the following scenario. Suppose you have to route agents through a network in some optimal way, for instance, by minimizing the total travel cost-nothing particular up to now-you could use a standard shortest-path algorithm. Suppose, however, that you want to avoid pure deterministic routing policies in order, for instance, to allow some continual exploration of the network, avoid congestion, or avoid complete predictability of your routing strategy. In other words, you want to introduce some randomness or unpredictability in the routing policy (i.e., the routing policy is randomized). This problem, which will be called the randomized shortest-path problem (RSP), is investigated in this work. The global level of randomness of the routing policy is quantified by the expected Shannon entropy spread throughout the network and is provided a priori by the designer. Then, necessary conditions to compute the optimal randomized policy-minimizing the expected routing cost-are derived. Iterating these necessary conditions, reminiscent of Bellman's value iteration equations, allows computing an optimal policy, that is, a set of transition probabilities in each node. Interestingly and surprisingly enough, this first model, while formulated in a totally different framework, is equivalent to Akamatsu's model ( 1996 ), appearing in transportation science, for a special choice of the entropy constraint. We therefore revisit Akamatsu's model by recasting it into a sum-over-paths statistical physics formalism allowing easy derivation of all the quantities of interest in an elegant, unified way. For instance, it is shown that the unique optimal policy can be obtained by
Random perfect lattices and the sphere packing problem.
Andreanov, A; Scardicchio, A
2012-10-01
Motivated by the search for best lattice sphere packings in Euclidean spaces of large dimensions we study randomly generated perfect lattices in moderately large dimensions (up to d=19 included). Perfect lattices are relevant in the solution of the problem of lattice sphere packing, because the best lattice packing is a perfect lattice and because they can be generated easily. Their number, however, grows superexponentially with the dimension, so to get an idea of their properties we propose to study a randomized version of the generating algorithm and to define a random ensemble with an effective temperature in a way reminiscent of a Monte Carlo simulation. We therefore study the distribution of packing fractions and kissing numbers of these ensembles and show how as the temperature is decreased the best known packers are easily recovered. We find that, even at infinite temperature, the typical perfect lattices are considerably denser than known families (like A(d) and D(d)), and we propose two hypotheses between which we cannot distinguish in this paper: one in which they improve the Minkowsky bound φ~2(-(0.84±0.06)d), and a competitor in which their packing fraction decreases superexponentially, namely, φ~d(-ad) but with a very small coefficient a=0.06±0.04. We also find properties of the random walk which are suggestive of a glassy system already for moderately small dimensions. We also analyze local structure of network of perfect lattices conjecturing that this is a scale-free network in all dimensions with constant scaling exponent 2.6±0.1.
Diffusion Processes Satisfying a Conservation Law Constraint
J. Bakosi
2014-01-01
Full Text Available We investigate coupled stochastic differential equations governing N nonnegative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires a set of fluctuating variables to be nonnegative and (if appropriately normalized sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the nonnegativity and the unit-sum conservation law constraints are satisfied as the variables evolve in time. We investigate the consequences of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have diffusion terms that are coupled and nonlinear. The set of constraints developed enables the development of statistical representations of fluctuating variables satisfying a conservation law. We exemplify the results with the bivariate beta process and the multivariate Wright-Fisher, Dirichlet, and Lochner’s generalized Dirichlet processes.
2005-01-01
We study the connection between the order of phase transitions in combinatorial problems and the complexity of decision algorithms for such problems. We rigorously show that, for a class of random constraint satisfaction problems, a limited connection between the two phenomena indeed exists. Specifically, we extend the definition of the spine order parameter of Bollobas et al. to random constraint satisfaction problems, rigorously showing that for such problems a discontinuity of the spine is...
Some open problems in random matrix theory and the theory of integrable systems
Deift, Percy
2007-01-01
We describe a list of open problems in random matrix theory and integrable systems which was presented at the conference ``Integrable Systems, Random Matrices, and Applications'' at the Courant Institute in May 2006.
Some open problems in random matrix theory and the theory of integrable systems
Deift, Percy
2007-01-01
We describe a list of open problems in random matrix theory and integrable systems which was presented at the conference ``Integrable Systems, Random Matrices, and Applications'' at the Courant Institute in May 2006.
λ-PDF AND GEGENBAUER POLYNOMIAL APPROXIMATION FOR DYNAMIC RESPONSE PROBLEMS OF RANDOM STRUCTURES
FANG Tong; LENG Xiaolei; MA Xiaoping; MENG Guang
2004-01-01
A bounded, mono-peak, and symmetrically distributed probability density function,called λ-PDF, together with the Gegenbauer polynomial approximation, is used in dynamic response problems of random structures. The λ-PDF can reasonably model a variety of random parameters in engineering random structures. The Gegenbauer polynomial approximation can be viewed as a new extension of the weighted residual method into the random space. Both of them can be easily used by scientists and engineers, and applied to a variety of response problems of random structures. The numerical example shows the effectiveness of the proposed method to study dynamic phenomena in random structures.
Optimization, Randomized Approximability, and Boolean Constraint Satisfaction Problems
Yamakami, Tomoyuki
2011-01-01
We give a unified treatment to optimization problems that can be expressed in the form of nonnegative-real-weighted Boolean constraint satisfaction problems. Creignou, Khanna, Sudan, Trevisan, and Williamson studied the complexity of approximating their optimal solutions whose optimality is measured by the sums of outcomes of constraints. To explore a wider range of optimization constraint satisfaction problems, following an early work of Marchetti-Spaccamela and Romano, we study the case where the optimality is measured by products of constraints' outcomes. We completely classify those problems into three categories: PO problems, NPO-hard problems, and intermediate problems that lie between the former two categories. To prove this trichotomy theorem, we analyze characteristics of nonnegative-real-weighted constraints using a variant of the notion of T-constructibility developed earlier for complex-weighted counting constraint satisfaction problems.
The Random Link Approximation for the Euclidean Traveling Salesman Problem
Cerf, N. J.; Boutet de Monvel, J.; Bohigas, O.; Martin, O. C.; Percus, A. G.
1997-01-01
The traveling salesman problem (TSP) consists of finding the length of the shortest closed tour visiting N “cities”. We consider the Euclidean TSP where the cities are distributed randomly and independently in a d-dimensional unit hypercube. Working with periodic boundary conditions and inspired by a remarkable universality in the kth nearest neighbor distribution, we find for the average optimum tour length voyageur de commerce (TSP) consiste à trouver le chemin fermé le plus court qui relie N “villes”. Nous étudions le TSP euclidien où les villes sont distribuées au hasard de manière décorrélée dans l'hypercube de côté 1, en dimension d. En imposant des conditions aux bords périodiques et guidés par une universalité remarquable de la distribution des kièmes voisins, nous trouvons la longueur moyenne du chemin optimal <~ngle L_Erangle = β_E(d)N^{1-1/d}[1+O(1/N)] , avec β_E= 0,7120 ± 0,0002 et β_E(3)= 0,6979 ± 0,0002. Nous établissons ensuite des prédictions analytiques sur ces quantités à l'aide de l'approximation de liens aléatoires, où les longueurs entre les villes sont des variables aléatoires indépendantes. Grâce aux équations “cavité” développées par Krauth, Mézard et Parisi, nous obtenons dans le cas de liens aléatoires les valeurs, β_RL(d), analogues à β_E(d). Pour d= 1, 2, 3, les résultats numériques confirment que l'approximation de liens aléatoires est bonne, conduisant à un écart inférieur à 2,1% entre β_E(d) et β_RL(d). Pour d grand, nous donnons des arguments montrant que cette approximation est exacte jusqu'à l'ordre 1/d^2 et nous proposons une conjecture pour β_E(d), exprimée en fonction d'une série en 1/d, dont on donne les deux premiers ordres.
Moments of random sums and Robbins' problem of optimal stopping
Gnedin, Alexander
2011-01-01
Robbins' problem of optimal stopping asks one to minimise the expected {\\it rank} of observation chosen by some nonanticipating stopping rule. We settle a conjecture regarding the {\\it value} of the stopped variable under the rule optimal in the sense of the rank, by embedding the problem in a much more general context of selection problems with the nonanticipation constraint lifted, and with the payoff growing like a power function of the rank.
Moments of random sums and Robbins' problem of optimal stopping
Gnedin, A.V.; Iksanov, A.
2011-01-01
Robbins' problem of optimal stopping is that of minimising the expected rank of an observation chosen by some nonanticipating stopping rule. We settle a conjecture regarding the value of the stopped variable under the rule that yields the minimal expected rank, by embedding the problem in a much
Moments of random sums and Robbins' problem of optimal stopping
Gnedin, A.V.; Iksanov, A.
2011-01-01
Robbins' problem of optimal stopping is that of minimising the expected rank of an observation chosen by some nonanticipating stopping rule. We settle a conjecture regarding the value of the stopped variable under the rule that yields the minimal expected rank, by embedding the problem in a much mor
On the Tractability of Un/Satisfiability
Salum, Latif
2014-01-01
The Petri net approach proves to be effective to tackle the $P$ vs $NP$ problem. A safe acyclic Petri net (PN) is associated with some Exactly-1 3SAT formula, in which a clause is an exactly-1 disjunction $\\dot{\\vee}$ of literals. A clause also corresponds to a set of conflicting transitions in the PN. Some 2SAT/XOR-SAT formula arisen in the inversed PN checks if the truth assignment of a literal (a transition firing) $z_v$ is "incompatible" for the satisfiability of the 3SAT formula (the rea...
Solving the constrained shortest path problem using random search strategy
无
2010-01-01
In this paper, we propose an improved walk search strategy to solve the constrained shortest path problem. The proposed search strategy is a local search algorithm which explores a network by walker navigating through the network. In order to analyze and evaluate the proposed search strategy, we present the results of three computational studies in which the proposed search algorithm is tested. Moreover, we compare the proposed algorithm with the ant colony algorithm and k shortest paths algorithm. The analysis and comparison results demonstrate that the proposed algorithm is an effective tool for solving the constrained shortest path problem. It can not only be used to solve the optimization problem on a larger network, but also is superior to the ant colony algorithm in terms of the solution time and optimal paths.
A new neural network model for solving random interval linear programming problems.
Arjmandzadeh, Ziba; Safi, Mohammadreza; Nazemi, Alireza
2017-05-01
This paper presents a neural network model for solving random interval linear programming problems. The original problem involving random interval variable coefficients is first transformed into an equivalent convex second order cone programming problem. A neural network model is then constructed for solving the obtained convex second order cone problem. Employing Lyapunov function approach, it is also shown that the proposed neural network model is stable in the sense of Lyapunov and it is globally convergent to an exact satisfactory solution of the original problem. Several illustrative examples are solved in support of this technique.
Newsvendor problem with random shortage cost under a risk criterion
Wu, Meng; Zhu, Stuart X.; Teunter, Ruud H.
2013-01-01
We study profit maximization vs risk approaches for the standard newsvendor problem with uncertainty in demand as well as a generalized version with uncertainty in the shortage cost (as often applies in practice). We consider two well-known risk approaches: Value-at-Risk (VaR) included as a constrai
Newsvendor problem with random shortage cost under a risk criterion
Wu, Meng; Zhu, Stuart X.; Teunter, Ruud H.
2013-01-01
We study profit maximization vs risk approaches for the standard newsvendor problem with uncertainty in demand as well as a generalized version with uncertainty in the shortage cost (as often applies in practice). We consider two well-known risk approaches: Value-at-Risk (VaR) included as a
The Application of Imperialist Competitive Algorithm for Fuzzy Random Portfolio Selection Problem
EhsanHesamSadati, Mir; Bagherzadeh Mohasefi, Jamshid
2013-10-01
This paper presents an implementation of the Imperialist Competitive Algorithm (ICA) for solving the fuzzy random portfolio selection problem where the asset returns are represented by fuzzy random variables. Portfolio Optimization is an important research field in modern finance. By using the necessity-based model, fuzzy random variables reformulate to the linear programming and ICA will be designed to find the optimum solution. To show the efficiency of the proposed method, a numerical example illustrates the whole idea on implementation of ICA for fuzzy random portfolio selection problem.
Problems in probability theory, mathematical statistics and theory of random functions
Sveshnikov, A A
1979-01-01
Problem solving is the main thrust of this excellent, well-organized workbook. Suitable for students at all levels in probability theory and statistics, the book presents over 1,000 problems and their solutions, illustrating fundamental theory and representative applications in the following fields: Random Events; Distribution Laws; Correlation Theory; Random Variables; Entropy & Information; Markov Processes; Systems of Random Variables; Limit Theorems; Data Processing; and more.The coverage of topics is both broad and deep, ranging from the most elementary combinatorial problems through lim
An Algorithm for Solving The Satisfiability Problem Based on Graph Matching%一种基于图匹配的求解可满足性问题的算法
于千城
2015-01-01
Message passing algorithms are very effective in finding satisfying assignments for SAT instances, and hard region be⁃come narrower. In the design of the Message passing algorithms, the joint probability distribution of the variables is decomposed in⁃to the product form of the local function of the variable quantum set. The local function is a factor, and each factor is dependent on a variable subset, which is represented as a graph model factor.Message passing algorithms is a kind of message passing through a factor graph, which has two ways:the variable node is passed to the message and the factor node of the node. The message from each node is determined by the decision of the incoming message, and the message is updated by an iterative strategy. When the convergence of this kind of message is fixed to a fixed point, the problem is solved by using some rules (e.g., minimum entropy, maximum product and maximum matching). In this paper, we propose a method to estimate the convergence and the upper bound of the algorithm. Based on the convergence analysis of the algorithm, we only need to give a reasonable number of iteration steps or forced the algorithm to terminate.%信息传播算法求解可满足性问题时具有良好的有效性，能使难解区域变窄。在信息传播算法的设计中，是将变量的联合概率分布分解为变量子集上的局部函数的乘积形式。称局部函数为因子(factor)，每一个因子依赖于一个变量子集，将变量联合分布的这一因子形式表示为图模型——因子图(factor graph)。信息传播算法是通过因子图上的边传递概率消息，这种消息传递有两种方式：变量结点传递给因子结点的消息和因子结点传递给变量结点的消息。从每个结点传出的消息由传入该结点的消息决定，通过某种迭代策略对消息进行更新。当这种消息迭代过程收敛到某一固定点时，利用某种规则（如，最小熵、最大
Efficient Analog Circuits for Boolean Satisfiability
Yin, Xunzhao; Varga, Melinda; Ercsey-Ravasz, Maria; Toroczkai, Zoltan; Hu, Xiaobo Sharon
2016-01-01
Efficient solutions to NP-complete problems would significantly benefit both science and industry. However, such problems are intractable on digital computers based on the von Neumann architecture, thus creating the need for alternative solutions to tackle such problems. Recently, a deterministic, continuous-time dynamical system (CTDS) was proposed (Nature Physics, 7(12), 966 (2011)) to solve a representative NP-complete problem, Boolean Satisfiability (SAT). This solver shows polynomial analog time-complexity on even the hardest benchmark $k$-SAT ($k \\geq 3$) formulas, but at an energy cost through exponentially driven auxiliary variables. With some modifications to the CTDS equations, here we present a novel analog hardware SAT solver, AC-SAT, implementing the CTDS. AC-SAT is intended to be used as a co-processor, and with its modular design can be readily extended to different problem sizes. The circuit is designed and simulated based on a 32nm CMOS technology. SPICE simulation results show speedup factor...
The Stochastic Galerkin Method for Darcy Flow Problem with Log-Normal Random Field Coefficients
Michal Beres
2017-01-01
Full Text Available This article presents a study of the Stochastic Galerkin Method (SGM applied to the Darcy flow problem with a log-normally distributed random material field given by a mean value and an autocovariance function. We divide the solution of the problem into two parts. The first one is the decomposition of a random field into a sum of products of a random vector and a function of spatial coordinates; this can be achieved using the Karhunen-Loeve expansion. The second part is the solution of the problem using SGM. SGM is a simple extension of the Galerkin method in which the random variables represent additional problem dimensions. For the discretization of the problem, we use a finite element basis for spatial variables and a polynomial chaos discretization for random variables. The results of SGM can be utilised for the analysis of the problem, such as the examination of the average flow, or as a tool for the Bayesian approach to inverse problems.
Halperin, S.; Zwick, U. [Tel Aviv Univ. (Israel)
1996-12-31
We present the first randomized O(log n) time and O(m + n) work EREW PRAM algorithm for finding a spanning forest of an undirected graph G = (V, E) with n vertices and m edges. Our algorithm is optimal with respect to time, work and space. As a consequence we get optimal randomized EREW PRAM algorithms for other basic connectivity problems such as finding a bipartite partition, finding bridges and biconnected components, and finding Euler tours in Eulerean graphs. For other problems such as finding an ear decomposition, finding an open ear decomposition, finding a strong orientation, and finding an st-numbering we get optimal randomized CREW PRAM algorithms.
Randomized Trial of Treatment for Children with Sexual Behavior Problems: Ten-Year Follow-Up
Carpentier, Melissa Y.; Silovsky, Jane F.; Chaffin, Mark
2006-01-01
This study prospectively follows 135 children 5-12 years of age with sexual behavior problems from a randomized trial comparing a 12-session group cognitive-behavioral therapy (CBT) with group play therapy and follows 156 general clinic children with nonsexual behavior problems. Ten-year follow-up data on future juvenile and adult arrests and…
Several applications of the theory of random conjugate spaces to measurability problems
2007-01-01
The central purpose of this paper is to illustrate that combining the recently developed theory of random conjugate spaces and the deep theory of Banach spaces can, indeed, solve some difficult measurability problems which occur in the recent study of the Lebesgue (or more general, Orlicz)-Bochner function spaces as well as in a slightly different way in the study of the random functional analysis but for which the measurable selection theorems currently available are not applicable. It is important that this paper provides a new method of studying a large class of the measurability problems, namely first converting the measurability problems to the abstract existence problems in the random metric theory and then combining the random metric theory and the relative theory of classical spaces so that the measurability problems can be eventually solved. The new method is based on the deep development of the random metric theory as well as on the subtle combination of the random metric theory with classical space theory.
A Study of the Optimum Lot Size and the Newsboy Problem Under Random Demands
Sira Allende Alonso
2004-02-01
Full Text Available The determination of the optimum lot size is a stochastic problem because of the randomness of the demands. The usual approaches consider that the involved distributions are known. We consider the case in which they are unknown. The optimization problem is probabilistic constraint program. The demands are modeled by an autoregressive process and the needed quantiles are derived. The newsboy problem is revisited using the derived results.
Multilevel variance estimators in MLMC and application for random obstacle problems
Chernov, Alexey
2014-01-06
The Multilevel Monte Carlo Method (MLMC) is a recently established sampling approach for uncertainty propagation for problems with random parameters. In this talk we present new convergence theorems for the multilevel variance estimators. As a result, we prove that under certain assumptions on the parameters, the variance can be estimated at essentially the same cost as the mean, and consequently as the cost required for solution of one forward problem for a fixed deterministic set of parameters. We comment on fast and stable evaluation of the estimators suitable for parallel large scale computations. The suggested approach is applied to a class of scalar random obstacle problems, a prototype of contact between deformable bodies. In particular, we are interested in rough random obstacles modelling contact between car tires and variable road surfaces. Numerical experiments support and complete the theoretical analysis.
Study on MAX-MIN Ant System with Random Selection in Quadratic Assignment Problem
Iimura, Ichiro; Yoshida, Kenji; Ishibashi, Ken; Nakayama, Shigeru
Ant Colony Optimization (ACO), which is a type of swarm intelligence inspired by ants' foraging behavior, has been studied extensively and its effectiveness has been shown by many researchers. The previous studies have reported that MAX-MIN Ant System (MMAS) is one of effective ACO algorithms. The MMAS maintains the balance of intensification and diversification concerning pheromone by limiting the quantity of pheromone to the range of minimum and maximum values. In this paper, we propose MAX-MIN Ant System with Random Selection (MMASRS) for improving the search performance even further. The MMASRS is a new ACO algorithm that is MMAS into which random selection was newly introduced. The random selection is one of the edgechoosing methods by agents (ants). In our experimental evaluation using ten quadratic assignment problems, we have proved that the proposed MMASRS with the random selection is superior to the conventional MMAS without the random selection in the viewpoint of the search performance.
Asymptotic property of solutions to the random cauchy problem for wave equations
Dôku, Isamu
1986-01-01
Based on the existence and uniqueness theorem for random wave equations, we consider asymptotic behaviors of solutions to the random initial value problem. We describe conditions for the equipartition of stochastic energy (or SE for short) by making use of the random spectral theory and, according to Goldstein's semigroup method, we prove the asymptotically equipartitioned SE theorem and the so-called virial theorem of classical mechanics, and also study the probabilistic characterization of the conditions for equipartition. In addition, we show at last the equipartition of SE from a finite time onwards.
ARE AUTHENTIC LEADERS SATISFIED WITH THEIR JOB?
Nebojsa Pavlovic
2016-06-01
Full Text Available A crisis in management has led to the appearance of Authentic leadership. The aim of this work is to determine the characteristics of Authentic leadership in educational institutions and to respond to the question as to whether authentic leaders are satisfied with their job. The third aim is to determine differences among the researched regions. The sample included 227 randomly selected directors from primary and secondary schools in Serbia, Montenegro and the Republika Srpska. The research used an ALQ questionnaire for the estimation of leadership behaviour. Descriptions for the results prediction and multiple linear regressions were used. A multivariance analysis of variance was used to compare the groups. The research results showed that every fourth director is an authentic leader. Authentic leadership has a significant influence on job satisfaction through two aspects: internalised perspective and balanced processing. There are no differences in Authentic leadership in the researched areas. The results could be useful for educational institutions in countries where the research was conducted. Further research could be carried out in other countries while cultural differences should be taken into account. One limiting factor consists of the fact that the analysed data are obtained only from school directors. Leaders of educational institutions should provide management through the development of their own authenticity and the authenticity of their followers. The characteristics of Authentic leadership were reviewed and tested practically in the West-Balkan environment.
A Numerical Study of the Performance of a Quantum Adiabatic Evolution Algorithm for Satisfiability
Farhi, E; Gutmann, S; Farhi, Edward; Goldstone, Jeffrey; Gutmann, Sam
2000-01-01
Quantum computation by adiabatic evolution, as described in quant-ph/0001106, will solve satisfiability problems if the running time is long enough. In certain special cases (that are classically easy) we know that the quantum algorithm requires a running time that grows as a polynomial in the number of bits. In this paper we present numerical results on randomly generated instances of an NP-complete problem and of a problem that can be solved classically in polynomial time. We simulate a quantum computer (of up to 16 qubits) by integrating the Schrodinger equation on a conventional computer. For both problems considered, for the set of instances studied, the required running time appears to grow slowly as a function of the number of bits.
A randomized controlled trial of an intervention for infants’ behavioral sleep problems
Hall, Wendy A.; Hutton, Eileen; Brant, Rollin F.; Collet, Jean Paul; Gregg, Kathy; Saunders, Roy; Ipsiroglu, Osman; Gafni, Amiram; Triolet, Kathy; Tse, Lillian; Bhagat, Radhika; Wooldridge, Joanne
2015-01-01
Background Infant behavioral sleep problems are common, with potential negative consequences. We conducted a randomized controlled trial to assess effects of a sleep intervention comprising a two-hour group teaching session and four support calls over 2 weeks. Our primary outcomes were reduced numbers of nightly wakes or parent report of sleep problem severity. Secondary outcomes included improvement in parental depression, fatigue, sleep, and parent cognitions about infant sleep. Methods Two...
Spectral Stochastic Finite Element Method for Electromagnetic Problems with Random Geometry
Lehikoinen Antti
2014-10-01
Full Text Available In electromagnetic problems, the problem geometry may not always be exactly known. One example of such a case is a rotating machine with random-wound windings. While spectral stochastic finite element methods have been used to solve statistical electromagnetic problems such as this, their use has been mainly limited to problems with uncertainties in material parameters only. This paper presents a simple method to solve both static and time-harmonic magnetic field problems with source currents in random positions. By using an indicator function, the geometric uncertainties are effectively reduced to material uncertainties, and the problem can be solved using the established spectral stochastic procedures. The proposed method is used to solve a demonstrative single-conductor problem, and the results are compared to the Monte Carlo method. Based on these simulations, the method appears to yield accurate mean values and variances both for the vector potential and current, converging close to the results obtained by time-consuming Monte Carlo analysis. However, further study may be needed to use the method for more complicated multi-conductor problems and to reduce the sensitivity of the method on the mesh used.
Open Problems in Applying Random-Matrix Theory to Nuclear Reactions
Weidenmueller, H A
2014-01-01
Problems in applying random-matrix theory (RMT) to nuclear reactions arise in two domains. To justify the approach, statistical properties of isolated resonances observed experimentally must agree with RMT predictions. That agreement is less striking than would be desirable. In the implementation of the approach, the range of theoretically predicted observables is too narrow.
Open problems in applying random-matrix theory to nuclear reactions
Weidenmüller, H. A.
2014-09-01
Problems in applying random-matrix theory (RMT) to nuclear reactions arise in two domains. To justify the approach, statistical properties of isolated resonances observed experimentally must agree with RMT predictions. That agreement is less striking than would be desirable. In the implementation of the approach, the range of theoretically predicted observables is too narrow.
Scheerlinck, N.; Verboven, P.; Stigter, J.D.; Baerdenmaeker, de J.; Impe, van J.F.; Nicolai, B.A.
2000-01-01
A first-order perturbation algorithm for the computation of mean values and variances of transient temperature and moisture fields during coupled heat and mass transfer problems with random field parameters has been developed and implemented. The algorithm is based on the Galerkin finite-element dis
Fast solution of NP-hard coloring problems on large random graphs
Bedini, Andrea
2010-01-01
Combining tree decomposition and transfer matrix techniques provides a highly efficient and very general algorithm for computing exact partition functions of statistical models defined on large graphs. We illustrate this by considering the hard problem of computing the exact number of vertex colorings for randomly generated planar graphs with up to N = 100 vertices.
EMDR versus CBT for children with self-esteem and behavioral problems: a randomized controlled trial
F. Wanders; M. Serra; A. de Jongh
2008-01-01
This study compared eye movement desensitization and reprocessing (EMDR) with cognitive-behavioral therapy (CBT). Twenty-six children (average age 10.4 years) with behavioral problems were randomly assigned to receive either 4 sessions of EMDR or CBT prior to usual treatment provided in outpatient a
The effect of random matter density perturbations on the MSW solution to the solar neutrino problem
Nunokawa, H; Semikoz, V B; Valle, José W F
1996-01-01
We consider the implications of solar matter density random noise upon resonant neutrino conversion. The evolution equation describing MSW-like conversion is derived in the framework of the Schr\\"odinger approach. We study quantitatively their effect upon both large and small mixing angle MSW solutions to the solar neutrino problem. This is carried out both for the active-active \
How Xenopus laevis embryos replicate reliably: investigating the random-completion problem
Yang, Scott Cheng-Hsin
2008-01-01
DNA synthesis in \\textit{Xenopus} frog embryos initiates stochastically in time at many sites (origins) along the chromosome. Stochastic initiation implies fluctuations in the time to complete and may lead to cell death if replication takes longer than the cell cycle time ($\\approx 25$ min). Surprisingly, although the typical replication time is about 20 min, \\textit{in vivo} experiments show that replication fails to complete only about 1 in 300 times. How is replication timing accurately controlled despite the stochasticity? Biologists have proposed two solutions to this "random-completion problem." The first solution uses randomly located origins but increases their rate of initiation as S phase proceeds, while the second uses regularly spaced origins. In this paper, we investigate the random-completion problem using a type of model first developed to describe the kinetics of first-order phase transitions. Using methods from the field of extreme-value statistics, we derive the distribution of replication-c...
K. Lenin
2013-03-01
Full Text Available Reactive Power Optimization is a complex combinatorial optimization problem involving non-linear function having multiple local minima, non-linear and discontinuous constrains. This paper presents Attractive and repulsive Particle Swarm Optimization (ARPSO and Random Virus Algorithm (RVA in trying to overcome the Problem of premature convergence. RVA and ARPSO is applied to Reactive Power Optimization problem and is evaluated on standard IEEE 30Bus System. The results show that RVA prevents premature convergence to high degree but still keeps a rapid convergence. It gives best solution when compared to Attractive and repulsive Particle Swarm Optimization (ARPSO and Particle Swarm Optimization (PSO.
Constraint programming for modelling and solving modal satisfiability
Brand, S.; Gennari, R.; de Rijke, M.
2003-01-01
We explore to what extent and how efficiently constraint programmingcan be used in the context of automated reasoning for modal logics. We encode modal satisfiability problems as constraint satisfactionproblems with non-boolean domains, together with suitable constraints.Experiments show that the ap
Constraint programming for modelling and solving modal satisfiability
Brand, S.; Gennari, R.; de Rijke, M.
2003-01-01
We explore to what extent and how efficiently constraint programmingcan be used in the context of automated reasoning for modal logics. We encode modal satisfiability problems as constraint satisfactionproblems with non-boolean domains, together with suitable constraints.Experiments show that the ap
Anantharaman, Arnaud
2010-01-01
This work is a follow-up to our previous work "A numerical approach related to defect-type theories for some weakly random problems in homogenization" (preprint available on this archive). It extends and complements, both theoretically and experimentally, the results presented there. Under consideration is the homogenization of a model of a weakly random heterogeneous material. The material consists of a reference periodic material randomly perturbed by another periodic material, so that its homogenized behavior is close to that of the reference material. We consider laws for the random perturbations more general than in our previous work cited above. We prove the validity of an asymptotic expansion in a certain class of settings. We also extend the formal approach introduced in our former work. Our perturbative approach shares common features with a defect-type theory of solid state physics. The computational efficiency of the approach is demonstrated.
SmArT solving: tools and techniques for satisfiability solvers
Heule, M.J.H.
2008-01-01
The satisfiability problem (Sat) lies at the core of the complexity theory. This is a decision problem: Not the solution itself, but whether or not a solution exists given a specified set of requirements is the central question. Over the years, the satisfiability problem has taken center stage as a
Siofra Petra Peeren
2014-08-01
Full Text Available Clinical depression affects approximately a fifth of older adults. It is important to assess the efficacy of psychological interventions in older adults because extant research indicates that treating depression with medication becomes complicated in later life. The current study evaluates the efficacy and long term effects of problem solving therapy (PST by systematically reviewing randomized trials of PST. A systematic search was undertaken of three computerised databases and six studies met the inclusion criteria. Studies indicated that PST was more effective than control conditions. However, the direct and long term effect of PST on depressive symptoms remains difficult to establish due to methodological issues.
Deterministic and randomized scheduling problems under the lp norm on two identical machines
LIN Ling; TAN Zhi-yi; HE Yong
2005-01-01
Parallel machine scheduling problems, which are important discrete optimization problems, may occur in many applications. For example, load balancing in network communication channel assignment, parallel processing in large-size computing, task arrangement in flexible manufacturing systems, etc., are multiprocessor scheduling problem. In the traditional parallel machine scheduling problems, it is assumed that the problems are considered in offline or online environment. But in practice, problems are often not really offline or online but somehow in-between. This means that, with respect to the online problem, some further information about the tasks is available, which allows the improvement of the performance of the best possible algorithms. Problems of this class are called semi-online ones. In this paper, the semi-online problem P2|decr|lp (p＞1) is considered where jobs come in non-increasing order of their processing times and the objective is to minimize the sum of the lp norm of every machine's load. It is shown that LS algorithm is optimal for any lp norm, which extends the results known in the literature. Furthermore, randomized lower bounds for the problems P2|online|lp and P2|decr|lp are presented.
Wade, Shari L; Walz, Nicolay C; Carey, JoAnne; McMullen, Kendra M; Cass, Jennifer; Mark, Erin; Yeates, Keith Owen
2012-11-01
To examine the results of a randomized clinical trial (RCT) of Teen Online Problem Solving (TOPS), an online problem solving therapy model, in increasing problem-solving skills and decreasing depressive symptoms and global distress for caregivers of adolescents with traumatic brain injury (TBI). Families of adolescents aged 11-18 who sustained a moderate to severe TBI between 3 and 19 months earlier were recruited from hospital trauma registries. Participants were assigned to receive a web-based, problem-solving intervention (TOPS, n = 20), or access to online resources pertaining to TBI (Internet Resource Comparison; IRC; n = 21). Parent report of problem solving skills, depressive symptoms, global distress, utilization, and satisfaction were assessed pre- and posttreatment. Groups were compared on follow-up scores after controlling for pretreatment levels. Family income was examined as a potential moderator of treatment efficacy. Improvement in problem solving was examined as a mediator of reductions in depression and distress. Forty-one participants provided consent and completed baseline assessments, with follow-up assessments completed on 35 participants (16 TOPS and 19 IRC). Parents in both groups reported a high level of satisfaction with both interventions. Improvements in problem solving skills and depression were moderated by family income, with caregivers of lower income in TOPS reporting greater improvements. Increases in problem solving partially mediated reductions in global distress. Findings suggest that TOPS may be effective in improving problem solving skills and reducing depressive symptoms for certain subsets of caregivers in families of adolescents with TBI.
Multiobjective Two-Stage Stochastic Programming Problems with Interval Discrete Random Variables
S. K. Barik
2012-01-01
Full Text Available Most of the real-life decision-making problems have more than one conflicting and incommensurable objective functions. In this paper, we present a multiobjective two-stage stochastic linear programming problem considering some parameters of the linear constraints as interval type discrete random variables with known probability distribution. Randomness of the discrete intervals are considered for the model parameters. Further, the concepts of best optimum and worst optimum solution are analyzed in two-stage stochastic programming. To solve the stated problem, first we remove the randomness of the problem and formulate an equivalent deterministic linear programming model with multiobjective interval coefficients. Then the deterministic multiobjective model is solved using weighting method, where we apply the solution procedure of interval linear programming technique. We obtain the upper and lower bound of the objective function as the best and the worst value, respectively. It highlights the possible risk involved in the decision-making tool. A numerical example is presented to demonstrate the proposed solution procedure.
Exchange rings satisfying power ideal-cancellation
陈焕艮
2003-01-01
In this paper, we introduce a new kind of partial power cancellations, and get a number of necessary and sufficient conditions for exchange rings satisfying power ideal-cancellation. These also extend many known results.
The Parity of Set Systems under Random Restrictions with Applications to Exponential Time Problems
Björklund, Andreas; Dell, Holger; Husfeldt, Thore
2015-01-01
We reduce the problem of detecting the existence of an object to the problem of computing the parity of the number of objects in question. In particular, when given any non-empty set system, we prove that randomly restricting elements of its ground set makes the size of the restricted set system...... and Husfeldt (FOCS 2013) that computes the parity of the number of Hamiltonian cycles in time 1.619^n. 2. A new result in the framework of Cygan et al. (CCC 2012) for analyzing the complexity of NP-hard problems under the Strong Exponential Time Hypothesis: If the parity of the number of Set Covers can...... an odd number with significant probability. When compared to previously known reductions of this type, ours excel in their simplicity: For graph problems, restricting elements of the ground set usually corresponds to simple deletion and contraction operations, which can be encoded efficiently in most...
The Parity of Set Systems under Random Restrictions with Applications to Exponential Time Problems
Björklund, Andreas; Dell, Holger; Husfeldt, Thore
2015-01-01
We reduce the problem of detecting the existence of an object to the problem of computing the parity of the number of objects in question. In particular, when given any non-empty set system, we prove that randomly restricting elements of its ground set makes the size of the restricted set system...... an odd number with significant probability. When compared to previously known reductions of this type, ours excel in their simplicity: For graph problems, restricting elements of the ground set usually corresponds to simple deletion and contraction operations, which can be encoded efficiently in most...... problems. We find three applications of our reductions: 1. An exponential-time algorithm: We show how to decide Hamiltonicity in directed n-vertex graphs with running time 1.9999^n provided that the graph has at most 1.0385^n Hamiltonian cycles. We do so by reducing to the algorithm of Björklund...
Biased Random-Key Genetic Algorithms for the Winner Determination Problem in Combinatorial Auctions.
de Andrade, Carlos Eduardo; Toso, Rodrigo Franco; Resende, Mauricio G C; Miyazawa, Flávio Keidi
2015-01-01
In this paper we address the problem of picking a subset of bids in a general combinatorial auction so as to maximize the overall profit using the first-price model. This winner determination problem assumes that a single bidding round is held to determine both the winners and prices to be paid. We introduce six variants of biased random-key genetic algorithms for this problem. Three of them use a novel initialization technique that makes use of solutions of intermediate linear programming relaxations of an exact mixed integer linear programming model as initial chromosomes of the population. An experimental evaluation compares the effectiveness of the proposed algorithms with the standard mixed linear integer programming formulation, a specialized exact algorithm, and the best-performing heuristics proposed for this problem. The proposed algorithms are competitive and offer strong results, mainly for large-scale auctions.
Complete Boolean Satisfiability Solving Algorithms Based on Local Search
Wen-Sheng Guo; Guo-Wu Yang; William N.N.Hung; Xiaoyu Song
2013-01-01
Boolean satisfiability (SAT) is a well-known problem in computer science,artificial intelligence,and operations research.This paper focuses on the satisfiability problem of Model RB structure that is similar to graph coloring problems and others.We propose a translation method and three effective complete SAT solving algorithms based on the characterization of Model RB structure.We translate clauses into a graph with exclusive sets and relative sets.In order to reduce search depth,we determine search order using vertex weights and clique in the graph.The results show that our algorithms are much more effective than the best SAT solvers in numerous Model RB benchmarks,especially in those large benchmark instances.
Franchin, P.; Ditlevsen, Ove Dalager; Kiureghian, Armen Der
2002-01-01
The model correction factor method (MCFM) is used in conjunction with the first-order reliability method (FORM) to solve structural reliability problems involving integrals of non-Gaussian random fields. The approach replaces the limit-state function with an idealized one, in which the integrals...... are considered to be Gaussian. Conventional FORM analysis yields the linearization point of the idealized limit-state surface. A model correction factor is then introduced to push the idealized limit-state surface onto the actual limit-state surface. A few iterations yield a good approximation of the reliability...... reliability method; Model correction factor method; Nataf field integration; Non-Gaussion random field; Random field integration; Structural reliability; Pile foundation reliability...
Long-time behavior of a Hele-Shaw type problem in random media
Pozar, Norbert
2010-01-01
We study the long-time behavior of an exterior Hele-Shaw problem in random media with a free boundary velocity that depends on position in dimensions $n \\geq 2$. A natural rescaling of solutions that is compatible with the evolution of the free boundary leads to homogenization of the free boundary velocity. By studying a limit obstacle problem for a Hele-Shaw system with a point source, we are able to show uniform convergence of the rescaled solution to a self-similar limit profile and we deduce that the rescaled free boundary uniformly approaches a sphere.
A Quantum Adiabatic Evolution Algorithm Applied to Random Instances of an NP-Complete Problem
Farhi, E; Gutmann, S; Lapan, J; Lundgren, A; Preda, D; Farhi, Edward; Goldstone, Jeffrey; Gutmann, Sam; Lapan, Joshua; Lundgren, Andrew; Preda, Daniel
2001-01-01
A quantum system will stay near its instantaneous ground state if the Hamiltonian that governs its evolution varies slowly enough. This quantum adiabatic behavior is the basis of a new class of algorithms for quantum computing. We test one such algorithm by applying it to randomly generated, hard, instances of an NP-complete problem. For the small examples that we can simulate, the quantum adiabatic algorithm works well, and provides evidence that quantum computers (if large ones can be built) may be able to outperform ordinary computers on hard sets of instances of NP-complete problems.
An Artificial Bee Colony Algorithm for the Job Shop Scheduling Problem with Random Processing Times
Rui Zhang
2011-09-01
Full Text Available Due to the influence of unpredictable random events, the processing time of each operation should be treated as random variables if we aim at a robust production schedule. However, compared with the extensive research on the deterministic model, the stochastic job shop scheduling problem (SJSSP has not received sufficient attention. In this paper, we propose an artificial bee colony (ABC algorithm for SJSSP with the objective of minimizing the maximum lateness (which is an index of service quality. First, we propose a performance estimate for preliminary screening of the candidate solutions. Then, the K-armed bandit model is utilized for reducing the computational burden in the exact evaluation (through Monte Carlo simulation process. Finally, the computational results on different-scale test problems validate the effectiveness and efficiency of the proposed approach.
How Xenopus laevis embryos replicate reliably: Investigating the random-completion problem
Yang, Scott Cheng-Hsin; Bechhoefer, John
2008-10-01
DNA synthesis in Xenopus frog embryos initiates stochastically in time at many sites (origins) along the chromosome. Stochastic initiation implies fluctuations in the time to complete and may lead to cell death if replication takes longer than the cell cycle time (≈25min) . Surprisingly, although the typical replication time is about 20min , in vivo experiments show that replication fails to complete only about 1 in 300 times. How is replication timing accurately controlled despite the stochasticity? Biologists have proposed two solutions to this “random-completion problem.” The first solution uses randomly located origins but increases their rate of initiation as S phase proceeds, while the second uses regularly spaced origins. In this paper, we investigate the random-completion problem using a type of model first developed to describe the kinetics of first-order phase transitions. Using methods from the field of extreme-value statistics, we derive the distribution of replication-completion times for a finite genome. We then argue that the biologists’ first solution to the problem is not only consistent with experiment but also nearly optimizes the use of replicative proteins. We also show that spatial regularity in origin placement does not alter significantly the distribution of replication times and, thus, is not needed for the control of replication timing.
Genetic analysis of leg problems and growth in a random mating broiler population.
González-Cerón, F; Rekaya, R; Anthony, N B; Aggrey, S E
2015-02-01
Improvement in growth has been widely reported as the cause of increased incidence of leg problems in broiler chickens. We report herein the genetic relationship between growth and leg problems in a random mating broiler control population. The traits studied were valgus (VL), varus (VR), and tibial dyschondroplasia (TD), which were expressed on a binary scale of 0 (normal) and 1 (abnormal); growth rates from 0 to 4 wk (BWG 0-4) and from 0 to 6 wk of age (BWG 0-6); and residual feed intake from 5 to 6 wk of age (RFI 5-6). A threshold-linear mixed model was employed for the joint analysis of the categorical and linear traits. Incidences of VL, VR, and TD were 26, 4, and 2%, respectively. Heritability of leg problems ranged from 0.11 to 0.13. Phenotypic correlations alluded to an unfavorable relationship between growth and leg problems; however, the genetic relationship between growth and leg problems was extremely weak, ranging from 0.01 to 0.08. There is, therefore, a basis for genetic improvement in leg problems. However, improved management practices would also be important to reduce incidence of leg problems in broiler chickens.
Orla Doyle
Full Text Available This study examined the impact of a targeted Irish early intervention program on children's emotional and behavioral development using multiple methods to test the robustness of the results. Data on 164 Preparing for Life participants who were randomly assigned into an intervention group, involving home visits from pregnancy onwards, or a control group, was used to test the impact of the intervention on Child Behavior Checklist scores at 24-months. Using inverse probability weighting to account for differential attrition, permutation testing to address small sample size, and quantile regression to characterize the distributional impact of the intervention, we found that the few treatment effects were largely concentrated among boys most at risk of developing emotional and behavioral problems. The average treatment effect identified a 13% reduction in the likelihood of falling into the borderline clinical threshold for Total Problems. The interaction and subgroup analysis found that this main effect was driven by boys. The distributional analysis identified a 10-point reduction in the Externalizing Problems score for boys at the 90th percentile. No effects were observed for girls or for the continuous measures of Total, Internalizing, and Externalizing problems. These findings suggest that the impact of this prenatally commencing home visiting program may be limited to boys experiencing the most difficulties. Further adoption of the statistical methods applied here may help to improve the internal validity of randomized controlled trials and contribute to the field of evaluation science more generally.ISRCTN Registry ISRCTN04631728.
CALL FOR PAPERS: Special issue on the random search problem: trends and perspectives
da Luz, Marcos G. E.; Grosberg, Alexander Y.; Raposo, Ernesto P.; Viswanathan, Gandhi M.
2008-11-01
This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to the subject of the random search problem. The motivation behind this special issue is to summarize in a single comprehensive publication, the main aspects (past and present), latest developments, different viewpoints and the directions being followed in this multidisciplinary field. We hope that such a special issue could become a particularly valuable reference for the broad scientific community working with the general random search problem. The Editorial Board has invited Marcos G E da Luz, Alexander Y Grosberg, Ernesto P Raposo and Gandhi M Viswanathan to serve as Guest Editors for the special issue. The general question of how to optimize the search for specific target objects in either continuous or discrete environments when the information available is limited is of significant importance in a broad range of fields. Representative examples include ecology (animal foraging, dispersion of populations), geology (oil recovery from mature reservoirs), information theory (automated researchers of registers in high-capacity database), molecular biology (proteins searching for their sites, e.g., on DNA ), etc. One reason underlying the richness of the random search problem relates to the `ignorance' of the locations of the randomly located `targets'. A statistical approach to the search problem can deal adequately with incomplete information and so stochastic strategies become advantageous. The general problem of how to search efficiently for randomly located target sites can thus be quantitatively described using the concepts and methods of statistical physics and stochastic processes. Scope Thus far, to the best of our knowledge, no recent textbook or review article in a physics journal has appeared on this topic. This makes a special issue with review and research articles attractive to those interested in acquiring a general introduction to the
Hierarchical satisfying optimal algorithm with different importance and priorities
Li Shaoyuan; Teng Changjun
2005-01-01
A hierarchical satisfying optimal algorithm incorporating different importance and preemptive priorities is formulated. With the priority structure given by the decision-maker in the constrained multi-objective multi-degree-of-freedom optimization (CMMO) problem, the commonly used quadratic programming model is converted into a two-level optimization problem solved by the tolerant lexicographic method and the varying-domain optimization method. In contrast to previous works, the proposed approach allows the decision-maker to determine a desirable achievement degree for each goal to reflect explicitly the relative importance of these goals. The resulting solutions satisfy both the preemptive priority structure and have the maximum achievement degrees in sum. The power of the proposed approach is demonstrated with an example.
Efficient Generation of Craig Interpolants in Satisfiability Modulo Theories
Cimatti, Alessandro; Sebastiani, Roberto
2009-01-01
The problem of computing Craig Interpolants has recently received a lot of interest. In this paper, we address the problem of efficient generation of interpolants for some important fragments of first order logic, which are amenable for effective decision procedures, called Satisfiability Modulo Theory solvers. We make the following contributions. First, we provide interpolation procedures for several basic theories of interest: the theories of linear arithmetic over the rationals, difference logic over rationals and integers, and UTVPI over rationals and integers. Second, we define a novel approach to interpolate combinations of theories, that applies to the Delayed Theory Combination approach. Efficiency is ensured by the fact that the proposed interpolation algorithms extend state of the art algorithms for Satisfiability Modulo Theories. Our experimental evaluation shows that the MathSAT SMT solver can produce interpolants with minor overhead in search, and much more efficiently than other competitor solve...
Observers for Systems with Nonlinearities Satisfying an Incremental Quadratic Inequality
Acikmese, Ahmet Behcet; Corless, Martin
2004-01-01
We consider the problem of state estimation for nonlinear time-varying systems whose nonlinearities satisfy an incremental quadratic inequality. These observer results unifies earlier results in the literature; and extend it to some additional classes of nonlinearities. Observers are presented which guarantee that the state estimation error exponentially converges to zero. Observer design involves solving linear matrix inequalities for the observer gain matrices. Results are illustrated by application to a simple model of an underwater.
Petry, Nancy M; Rash, Carla J; Alessi, Sheila M
2016-10-01
This study evaluated the efficacy of brief gambling treatments in patients attending substance abuse treatment clinics. Substance abuse treatment patients with gambling problems (N = 217) were randomly assigned to a 10- to 15-min brief psychoeducation gambling intervention; a 10- to 15-min brief advice intervention addressing gambling norms, risk factors, and methods to prevent additional problems; or 4 50-min sessions of motivational enhancement therapy plus cognitive behavior therapy for reducing gambling (MET + CBT). Gambling and related problems were assessed at baseline and throughout 24 months. In the sample as a whole, days and dollars wagered and gambling problems decreased markedly from baseline through Month 5; thereafter, reductions in dollars wagered and gambling problems continued to decrease modestly but significantly, and days gambled remained constant. Brief advice significantly reduced days gambled between baseline and Month 5 relative to brief psychoeducation. The MET + CBT condition engendered no benefit beyond brief advice in terms of days gambled but did lead to more precipitous reductions in dollars gambled and problems experienced in the initial 5 months, and greater clinically significant improvements in gambling in both the short and long term. MET + CBT also resulted in initial decreases in self-reported alcohol use and problems but did not differentially impact self-reported illicit drug use or submission of positive samples. Gambling problems tend to dissipate over time regardless of the intervention applied, but offering MET + CBT was more efficacious in decreasing gambling than providing a brief single session intervention. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Remarks on homogeneous manifolds satisfying Levi conditions
Huckleberry, Alan
2010-01-01
Homogeneous complex manifolds satisfying various types of Levi conditions are considered. Classical results which were of particular interest to Andreotti are recalled. Convexity and concavity properties of flag domains are discussed in some detail. A precise classification of pseudoconvex flag domains is given. It is shown that flag domains which are in a certain sense generic are pseudoconcave.
Construction of plateaued functions satisfying multiple criteria
Zhang Weiguo
2005-01-01
A class of plateaued functions has been got by using the Maiorana-McFarland construction. A variety of desirable criteria for functions with cryptographic application could be satisfied: balancedness, high nonlinearity, correlation immunity of reasonably high order, strict avalanche criterion, non-existence of non-zero linear structures, good global avalanche characteristics, etc.
Large mixing angle solution to the solar neutrino problem and random matter density perturbations
Guzzo, M M; Reggiani, N
2003-01-01
There are reasons to believe that mechanisms exist in the solar interior which lead to random density perturbations in the resonant region of the Large Mixing Angle solution to the solar neutrino problem. We find that, in the presence of these density perturbations, the best fit point in the (sin^2(2\\theta), Delta_m^2) parameter space moves to smaller values, compared with the values obtained for the standard LMA solution. Combining solar data with KamLAND results, we find a new compatibility region, which we call VERY-LOW LMA, where sin^2(2\\theta) ~ 0.6 and Delta_m^2~2e-5 eV^2, for random density fluctuations of order 5% < \\xi< 8%. We argue that such values of density fluctuations are still allowed by helioseismological observations at small scales of order 10 - 1000 km deep inside the solar core.
Planning and problem-solving training for patients with schizophrenia: a randomized controlled trial
Backenstraß Matthias
2011-04-01
Full Text Available Abstract Background The purpose of this study was to assess whether planning and problem-solving training is more effective in improving functional capacity in patients with schizophrenia than a training program addressing basic cognitive functions. Methods Eighty-nine patients with schizophrenia were randomly assigned either to a computer assisted training of planning and problem-solving or a training of basic cognition. Outcome variables included planning and problem-solving ability as well as functional capacity, which represents a proxy measure for functional outcome. Results Planning and problem-solving training improved one measure of planning and problem-solving more strongly than basic cognition training, while two other measures of planning did not show a differential effect. Participants in both groups improved over time in functional capacity. There was no differential effect of the interventions on functional capacity. Conclusion A differential effect of targeting specific cognitive functions on functional capacity could not be established. Small differences on cognitive outcome variables indicate a potential for differential effects. This will have to be addressed in further research including longer treatment programs and other settings. Trial registration ClinicalTrials.gov NCT00507988
Implicit theories and youth mental health problems: a random-effects meta-analysis.
Schleider, Jessica L; Abel, Madelaine R; Weisz, John R
2015-02-01
Compared to youths who believe that personal traits are malleable, those who believe that personal traits are fixed experience more academic and self-regulatory distress. Recently, studies have begun to explore relations between beliefs about the malleability of personal traits, or implicit theories, and youth mental health problems. We synthesized this emerging body of research in youths (ages 4-19) across 45 effect sizes from 17 research reports. Studies were included if they assessed youth mental health and implicit theories and did not manipulate implicit theory or affective/behavioral states prior to measuring these variables. Our random-effects meta-analysis using clustered data analysis techniques (i.e., effect sizes nested within samples) revealed that youths holding entity theories-the belief that personal traits are fixed-showed more pronounced mental health problems. This association between entity theories and mental health problems was evident across methodological factors and problem types (internalizing versus externalizing; psychopathology versus general distress). Limitations include the small number of eligible studies, insufficient data to test further demographic moderators, and few longitudinal studies on this topic. Overall, findings support the value of parsing the implicit theory-mental health link in youths. Implicit theories may prove to be promising targets for treatment and prevention of youth mental health problems.
Xi F. XU
2015-01-01
The Green-function-based multiscale stochastic finite element method （MSFEM） has been formulated based on the stochastic variational principle. In this study a fast computing procedure based on the MSFEM is developed to solve random field geotechnical problems with a typical coefficient of variance less than 1. A unique fast computing advantage of the procedure enables computation performed only on those locations of interest, therefore saving a lot of computation. The numerical example on soil settlement shows that the procedure achieves significant computing efficiency compared with Monte Carlo method.
Random location of multiple sparse priors for solving the MEG/EEG inverse problem.
Lopez, Jose D; Espinosa, Jairo J; Barnes, Gareth R
2012-01-01
MEG/EEG brain imaging has become an important tool in neuroimaging. Current techniques based in Bayesian approaches require an a-priori definition of patch locations on the cortical manifold. Too many patches results in a complex optimisation problem, too few an under sampling of the solution space. In this work random locations of the possible active regions of the brain are proposed to iteratively arrive at a solution. We use Bayesian model averaging to combine different possible solutions. The proposed methodology was tested with synthetic MEG datasets reducing the localisation error of the approaches based on fixed locations. Real data from a visual attention study was used for validation.
Restricted random search method based on taboo search in the multiple minima problem
Hong, Seung Do; Jhon, Mu Shik
1997-03-01
The restricted random search method is proposed as a simple Monte Carlo sampling method to search minima fast in the multiple minima problem. This method is based on taboo search applied recently to continuous test functions. The concept of the taboo region instead of the taboo list is used and therefore the sampling of a region near an old configuration is restricted in this method. This method is applied to 2-dimensional test functions and the argon clusters. This method is found to be a practical and efficient method to search near-global configurations of test functions and the argon clusters.
Inverse acoustic scattering problem in half-space with anisotropic random impedance
Helin, Tapio; Lassas, Matti; Päivärinta, Lassi
2017-02-01
We study an inverse acoustic scattering problem in half-space with a probabilistic impedance boundary value condition. The Robin coefficient (surface impedance) is assumed to be a Gaussian random function with a pseudodifferential operator describing the covariance. We measure the amplitude of the backscattered field averaged over the frequency band and assume that the data is generated by a single realization of λ. Our main result is to show that under certain conditions the principal symbol of the covariance operator of λ is uniquely determined. Most importantly, no approximations are needed and we can solve the full non-linear inverse problem. We concentrate on anisotropic models for the principal symbol, which leads to the analysis of a novel anisotropic spherical Radon transform and its invertibility.
Fuchs, Lynn S.; Zumeta, Rebecca O.; Schumacher, Robin Finelli; Powell, Sarah R.; Seethaler, Pamela M.; Hamlett, Carol L.; Fuchs, Douglas
2010-01-01
The purpose of this study was to assess the effects of schema-broadening instruction (SBI) on second graders’ word-problem-solving skills and their ability to represent the structure of word problems using algebraic equations. Teachers (n = 18) were randomly assigned to conventional word-problem instruction or SBI word-problem instruction, which taught students to represent the structural, defining features of word problems with overarching equations. Intervention lasted 16 weeks. We pretested and posttested 270 students on measures of word-problem skill; analyses that accounted for the nested structure of the data indicated superior word-problem learning for SBI students. Descriptive analyses of students’ word-problem work indicated that SBI helped students represent the structure of word problems with algebraic equations, suggesting that SBI promoted this aspect of students’ emerging algebraic reasoning. PMID:20539822
Particle swarm optimization with random keys applied to the nuclear reactor reload problem
Meneses, Anderson Alvarenga de Moura [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Nuclear; Fundacao Educacional de Macae (FUNEMAC), RJ (Brazil). Faculdade Professor Miguel Angelo da Silva Santos; Machado, Marcelo Dornellas; Medeiros, Jose Antonio Carlos Canedo; Schirru, Roberto [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Nuclear]. E-mails: ameneses@con.ufrj.br; marcelo@lmp.ufrj.br; canedo@lmp.ufrj.br; schirru@lmp.ufrj.br
2007-07-01
In 1995, Kennedy and Eberhart presented the Particle Swarm Optimization (PSO), an Artificial Intelligence metaheuristic technique to optimize non-linear continuous functions. The concept of Swarm Intelligence is based on the socials aspects of intelligence, it means, the ability of individuals to learn with their own experience in a group as well as to take advantage of the performance of other individuals. Some PSO models for discrete search spaces have been developed for combinatorial optimization, although none of them presented satisfactory results to optimize a combinatorial problem as the nuclear reactor fuel reloading problem (NRFRP). In this sense, we developed the Particle Swarm Optimization with Random Keys (PSORK) in previous research to solve Combinatorial Problems. Experiences demonstrated that PSORK performed comparable to or better than other techniques. Thus, PSORK metaheuristic is being applied in optimization studies of the NRFRP for Angra 1 Nuclear Power Plant. Results will be compared with Genetic Algorithms and the manual method provided by a specialist. In this experience, the problem is being modeled for an eight-core symmetry and three-dimensional geometry, aiming at the minimization of the Nuclear Enthalpy Power Peaking Factor as well as the maximization of the cycle length. (author)
Satisfiability of ATL with strategy contexts
François Laroussinie
2013-07-01
Full Text Available Various extensions of the temporal logic ATL have recently been introduced to express rich properties of multi-agent systems. Among these, ATLsc extends ATL with strategy contexts, while Strategy Logic has first-order quantification over strategies. There is a price to pay for the rich expressiveness of these logics: model-checking is non-elementary, and satisfiability is undecidable. We prove in this paper that satisfiability is decidable in several special cases. The most important one is when restricting to turn-based games. We prove that decidability also holds for concurrent games if the number of moves available to the agents is bounded. Finally, we prove that restricting strategy quantification to memoryless strategies brings back undecidability.
A watermarking algorithm satisfying topological chaos properties
Bahi, Jacques M
2008-01-01
A new watermarking algorithm is given, it is based on the so-called chaotic iterations and on the choice of some coefficients which are deduced from the description of the carrier medium. After defining these coefficients, chaotic discrete iterations are used to encrypt the watermark and to embed it in the carrier medium. This procedure generates a topological chaos and ensures that the required properties of a watermarking algorithm are satisfied. Key-words: Watermarking, Encryption, Chaotic iterations, Topological chaos, Information hiding
Superrosy dependent groups having finitely satisfiable generics
Ealy, Clifton; Pillay, Anand
2007-01-01
We study a model theoretic context (finite thorn rank, NIP, with finitely satisfiable generics) which is a common generalization of groups of finite Morley rank and definably compact groups in o-minimal structures. We show that assuming thorn rank 1, the group is abelian-by-finite, and assuming thorn rank 2 the group is solvable by finite. Also a field is algebraically closed.
The monomer-dimer problem and moment Lyapunov exponents of homogeneous Gaussian random fields
Vladimirov, Igor G
2012-01-01
We consider an "elastic" version of the statistical mechanical monomer-dimer problem on the n-dimensional integer lattice. Our setting includes the classical "rigid" formulation as a special case and extends it by allowing each dimer to consist of particles at arbitrarily distant sites of the lattice, with the energy of interaction between the particles in a dimer depending on their relative position. We reduce the free energy of the elastic dimer-monomer (EDM) system per lattice site in the thermodynamic limit to the moment Lyapunov exponent (MLE) of a homogeneous Gaussian random field (GRF) whose mean value and covariance function are the Boltzmann factors associated with the monomer energy and dimer potential. In particular, the classical monomer-dimer problem becomes related to the MLE of a moving average GRF. We outline an approach to recursive computation of the partition function for "Manhattan" EDM systems where the dimer potential is a weighted l1-distance and the auxiliary GRF is a Markov random fie...
A randomized Mirror-Prox method for solving structured large-scale matrix saddle-point problems
Baes, Michel; Nemirovski, Arkadi
2011-01-01
In this paper, we derive a randomized version of the Mirror-Prox method for solving some structured matrix saddle-point problems, such as the maximal eigenvalue minimization problem. Deterministic first-order schemes, such as Nesterov's Smoothing Techniques or standard Mirror-Prox methods, require the exact computation of a matrix exponential at every iteration, limiting the size of the problems they can solve. Our method allows us to use stochastic approximations of matrix exponentials. We prove that our randomized scheme decreases significantly the complexity of its deterministic counterpart for large-scale matrix saddle-point problems. Numerical experiments illustrate and confirm our theoretical results.
Dambrine, M.; Greff, I.; Harbrecht, H.; Puig, B.
2017-02-01
The present article is dedicated to the numerical solution of homogeneous Neumann boundary value problems on domains with a thin layer of different conductivity and of random thickness. By changing the boundary condition, the boundary value problem given on the random domain can be transformed into a boundary value problem on a fixed domain. The randomness is then contained in the coefficients of the new boundary condition. This thin coating can be expressed by a random Ventcell boundary condition and yields a second order accurate solution in the scale parameter ε of the layer's thickness. With the help of the Karhunen-Loève expansion, we transform this random boundary value problem into a deterministic, parametric one with a possibly high-dimensional parameter y. Based on the decay of the random fluctuations of the layer's thickness, we prove rates of decay of the derivatives of the random solution with respect to this parameter y which are robust in the scale parameter ε. Numerical results validate our theoretical findings.
Phase transition in a random fragmentation problem with applications to computer science
Dean, David S.; Majumdar, Satya N. [IRSAMC, Laboratoire de Physique Quantique (UMR 5626 du CNRS), Universite Paul Sabatier, Toulouse (France)
2002-08-16
We study a fragmentation problem where an initial object of size x is broken into m random pieces provided x>x{sub 0} where x{sub 0} is an atomic cut-off. Subsequently, the fragmentation process continues for each of those daughter pieces whose sizes are bigger than x{sub 0}. The process stops when all the fragments have sizes smaller than x{sub 0}. We show that the fluctuation of the total number of splitting events, characterized by the variance, generically undergoes a nontrivial phase transition as one tunes the branching number m through a critical value m=m{sub c}. For m
VLSI Circuit Configuration Using Satisfiability Logic in Hopfield Network
Mohd Asyraf Mansor
2016-09-01
Full Text Available Very large scale integration (VLSI circuit comprises of integrated circuit (IC with transistors in a single chip, widely used in many sophisticated electronic devices. In our paper, we proposed VLSI circuit design by implementing satisfiability problem in Hopfield neural network as circuit verification technique. We restrict our logic construction to 2-Satisfiability (2-SAT and 3- Satisfiability (3-SAT clauses in order to suit with the transistor configuration in VLSI circuit. In addition, we developed VLSI circuit based on Hopfield neural network in order to detect any possible error earlier than the manual circuit design. Microsoft Visual C++ 2013 is used as a platform for training, testing and validating of our proposed design. Hence, the performance of our proposed technique evaluated based on global VLSI configuration, circuit accuracy and the runtime. It has been observed that the VLSI circuits (HNN-2SAT and HNN-3SAT circuit developed by proposed design are better than the conventional circuit due to the early error detection in our circuit.
Observers for a class of systems with nonlinearities satisfying an incremental quadratic inequality
Acikmese, Ahmet Behcet; Martin, Corless
2004-01-01
We consider the problem of state estimation from nonlinear time-varying system whose nonlinearities satisfy an incremental quadratic inequality. Observers are presented which guarantee that the state estimation error exponentially converges to zero.
Robinson, Robert G; Jorge, Ricardo E; Moser, David J; Acion, Laura; Solodkin, Ana; Small, Steven L; Fonzetti, Pasquale; Hegel, Mark; Arndt, Stephan
2008-05-28
Depression occurs in more than half of patients who have experienced a stroke. Poststroke depression has been shown in numerous studies to be associated with both impaired recovery in activities of daily living and increased mortality. Prevention of depression thus represents a potentially important goal. To determine whether treatment with escitalopram or problem-solving therapy over the first year following acute stroke will decrease the number of depression cases that develop compared with placebo medication. A multisite randomized controlled trial for prevention of depression among 176 nondepressed patients was conducted within 3 months following acute stroke from July 9, 2003, to October 1, 2007. The 12-month trial included 3 groups: a double-blind placebo-controlled comparison of escitalopram (n = 59) with placebo (n = 58), and a nonblinded problem-solving therapy group (n = 59). The main outcome measure was the development of major or minor poststroke depression based on symptoms elicited by the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) (DSM-IV) and the diagnostic criteria from DSM-IV for depression due to stroke with major depressive-like episode or minor depression (ie, research criteria). Patients who received placebo were significantly more likely to develop depression than individuals who received escitalopram (11 major and 2 minor cases of depression [22.4%] vs 3 major and 2 minor cases of depression [8.5%], adjusted hazard ratio [HR], 4.5; 95% confidence interval [CI], 2.4-8.2; P < .001) and also more likely than individuals who received problem-solving therapy (5 major and 2 minor cases of depression [11.9%], adjusted HR, 2.2; 95% CI, 1.4-3.5; P < .001). These results were adjusted for history of mood disorders and remained significant after considering possible confounders such as age, sex, treatment site, and severity of impairment in the model. Using an intention
Borsari, Brian; Hustad, John T.P.; Mastroleo, Nadine R.; Tevyaw, Tracy O’Leary; Barnett, Nancy P.; Kahler, Christopher W.; Short, Erica Eaton; Monti, Peter M.
2012-01-01
Objective Over the past two decades, colleges and universities have seen a large increase in the number of students referred to the administration for alcohol policies violations. However, a substantial portion of mandated students may not require extensive treatment. Stepped care may maximize treatment efficiency and greatly reduce the demands on campus alcohol programs. Method Participants in the study (N = 598) were college students mandated to attend an alcohol program following a campus-based alcohol citation. All participants received Step 1: a 15-minute Brief Advice session that included the provision of a booklet containing advice to reduce drinking. Participants were assessed six weeks after receiving the Brief Advice, and those who continued to exhibit risky alcohol use (n = 405) were randomized to Step 2, a 60–90 minute brief motivational intervention (BMI) (n = 211) or an assessment-only control (n = 194). Follow-up assessments were conducted 3, 6, and 9 months after Step 2. Results Results indicated that the participants who received a BMI significantly reduced the number of alcohol-related problems compared to those who received assessment-only, despite no significant group differences in alcohol use. In addition, low risk drinkers (n = 102; who reported low alcohol use and related harms at 6-week follow-up and were not randomized to stepped care) showed a stable alcohol use pattern throughout the follow-up period, indicating they required no additional intervention. Conclusion Stepped care is an efficient and cost-effective method to reduce harms associated with alcohol use by mandated students. PMID:22924334
Learning Techniques for Automatic Test Pattern Generation using Boolean Satisfiability
Liu Xin
2013-07-01
Full Text Available Automatic Test Pattern Generation (ATPG is one of the core problems in testing of digital circuits. ATPG algorithms based on Boolean Satisfiability (SAT turned out to be very powerful, due to great advances in the performance of satisfiability solvers for propositional logic in the last two decades. SAT-based ATPG clearly outperforms classical approaches especially for hard-to-detect faults. But its inaccessibility of structural information and don’t care, there exists the over-specification problem of input patterns. In this paper we present techniques to delve into an additional layer to make use of structural properties of the circuit and value justification relations to a generic SAT algorithm. It joins binary decision graphs (BDD and SAT techniques to improve the efficiency of ATPG. It makes a study of inexpensive reconvergent fanout analysis of circuit to gather information on the local signal correlation by using BDD learning, then uses the above learned information to restrict and focus the overall search space of SAT-based ATPG. The learning technique is effective and lightweight. Experimental results show the effectiveness of the approach.
Kalchev, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ketelsen, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, P. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2013-11-07
Our paper proposes an adaptive strategy for reusing a previously constructed coarse space by algebraic multigrid to construct a two-level solver for a problem with nearby characteristics. Furthermore, a main target application is the solution of the linear problems that appear throughout a sequence of Markov chain Monte Carlo simulations of subsurface flow with uncertain permeability field. We demonstrate the efficacy of the method with extensive set of numerical experiments.
Dry, Matthew J.; Preiss, Kym; Wagemans, Johan
2012-01-01
We investigated human performance on the Euclidean Traveling Salesperson Problem (TSP) and Euclidean Minimum Spanning Tree Problem (MST-P) in regards to a factor that has previously received little attention within the literature: the spatial distributions of TSP and MST-P stimuli. First, we describe a method for quantifying the relative degree of…
Differences Between Highly Satisfied and Not Highly Satisfied Clients of Day Care Centers.
Handler, Ellen; Fredlund, Janet
This study analyzes the differences between those customers in two types of day care centers who are highly satisfied and who are not. Half were supported by client fees, and half used other sources of funding, e.g. tax support, and private philanthropic support. Parents and teachers of 100 children in day care centers in four different…
satisfies probabilistic k-anonymity criterion
Anna Oganian
2017-04-01
Full Text Available Before releasing databases which contain sensitive information about individuals, data publishers must apply Statistical Disclosure Limitation (SDL methods to them, in order to avoid disclosure of sensitive information on any identifiable data subject. SDL methods often consist of masking or synthesizing the original data records in such a way as to minimize the risk of disclosure of the sensitive information while providing data users with accurate information about the population of interest. In this paper we propose a new scheme for disclosure limitation, based on the idea of local synthesis of data. Our approach is predicated on model-based clustering. The proposed method satisfies the requirements of k-anonymity; in particular we use a variant of the k-anonymity privacy model, namely probabilistic k-anonymity, by incorporating constraints on cluster cardinality. Regarding data utility, for continuous attributes, we exactly preserve means and covariances of the original data, while approximately preserving higher-order moments and analyses on subdomains (defined by clusters and cluster combinations. For both continuous and categorical data, our experiments with medical data sets show that, from the point of view of data utility, local synthesis compares very favorably with other methods of disclosure limitation including the sequential regression approach for synthetic data generation.
An efficient algorithm for the vertex-disjoint paths problem in random graphs
Broder, A.Z. [Digital Systems Research Center, Palo Alto, CA (United States); Frieze, A.M.; Suen, S. [Carnegie-Mellon Univ., Pittsburgh, PA (United States); Upfal, E. [IBM Almaden Research Center, San Jose, CA (United States)
1996-12-31
Given a graph G = (V, E) and a set of pairs of vertices in V, we are interested in finding for each pair (a{sub i}, b{sub i}) a path connecting a{sub i} to b{sub i}, such that the set of paths so found is vertex-disjoint. (The problem is NP-complete for general graphs as well as for planar graphs. It is in P if the number of pairs is fixed.) Our model is that the graph is chosen first, then an adversary chooses the pairs of endpoints, subject only to obvious feasibility constraints, namely, all pairs must be disjoint, no more than a constant fraction of the vertices could be required for the paths, and not {open_quotes}too many{close_quotes} neighbors of a vertex can be endpoints. We present a randomized polynomial time algorithm that works for almost all graphs; more precisely in the G{sub n,m} or G{sub n,p} models, the algorithm succeeds with high probability for all edge densities above the connectivity threshold. The set of pairs that can be accommodated is optimal up to constant factors. Although the analysis is intricate, the algorithm itself is quite simple and suggests a practical heuristic. We include two applications of the main result, one in the context of circuit switching communication, the other in the context of topological embeddings of graphs.
Williams K
2014-06-01
Full Text Available Kristine Williams,1 Ruth Herman,2 Daniel Bontempo3 1College of Nursing, University of Iowa, Iowa City, IA, USA; 2School of Nursing, University of Kansas Medical Center, Kansas City, KS, USA; 3The Schiefelbusch Institute for Life Span Studies, University of Kansas, Dole Human Development Center, Lawrence, KS, USA Purpose of the study: Assisted living (AL residents are at risk for cognitive and functional declines that eventually reduce their ability to care for themselves, thereby triggering nursing home placement. In developing a method to slow this decline, the efficacy of Reasoning Exercises in Assisted Living (REAL, a cognitive training intervention that teaches everyday reasoning and problem-solving skills to AL residents, was tested. Design and methods: At thirteen randomized Midwestern facilities, AL residents whose Mini Mental State Examination scores ranged from 19–29 either were trained in REAL or a vitamin education attention control program or received no treatment at all. For 3 weeks, treated groups received personal training in their respective programs. Results: Scores on the Every Day Problems Test for Cognitively Challenged Elders (EPCCE and on the Direct Assessment of Functional Status (DAFS showed significant increases only for the REAL group. For EPCCE, change from baseline immediately postintervention was +3.10 (P<0.01, and there was significant retention at the 3-month follow-up (d=2.71; P<0.01. For DAFS, change from baseline immediately postintervention was +3.52 (P<0.001, although retention was not as strong. Neither the attention nor the no-treatment control groups had significant gains immediately postintervention or at follow-up assessments. Post hoc across-group comparison of baseline change also highlights the benefits of REAL training. For EPCCE, the magnitude of gain was significantly larger in the REAL group versus the no-treatment control group immediately postintervention (d=3.82; P<0.01 and at the 3-month
Ma, Yanfang; Xu, Jiuping
2015-06-01
This article puts forward a cloud theory-based particle swarm optimization (CTPSO) algorithm for solving a variant of the vehicle routing problem, namely a multiple decision maker vehicle routing problem with fuzzy random time windows (MDVRPFRTW). A new mathematical model is developed for the proposed problem in which fuzzy random theory is used to describe the time windows and bi-level programming is applied to describe the relationship between the multiple decision makers. To solve the problem, a cloud theory-based particle swarm optimization (CTPSO) is proposed. More specifically, this approach makes improvements in initialization, inertia weight and particle updates to overcome the shortcomings of the basic particle swarm optimization (PSO). Parameter tests and results analysis are presented to highlight the performance of the optimization method, and comparison of the algorithm with the basic PSO and the genetic algorithm demonstrates its efficiency.
Jitendra, Asha K; Harwell, Michael R; Dupuis, Danielle N; Karl, Stacy R
This article reports results from a study investigating the efficacy of a proportional problem-solving intervention, schema-based instruction (SBI), in seventh grade. Participants included 806 students with mathematical difficulties in problem solving (MD-PS) from an initial pool of 1,999 seventh grade students in a larger study. Teachers and their students in the larger study were randomly assigned to an SBI or control condition and teachers in both conditions then provided instruction on the topics of ratio, proportion, and percent. We found that students with MD-PS in SBI classrooms scored on average higher than their counterparts in control classrooms on a posttest and delayed posttest administered 9 weeks later. Given students' difficulties with proportional problem-solving and the consequences of these difficulties, an important contribution of this research is the finding that when provided with appropriate instruction, students with MD-PS are capable of enhanced proportional problem-solving performance.
Newton, J. Stephen; Horner, Robert H.; Algozzine, Bob; Todd, Anne W.; Algozzine, Kate
2012-01-01
Members of Positive Behavior Interventions and Supports (PBIS) teams from 34 elementary schools participated in a Team-Initiated Problem Solving (TIPS) Workshop and follow-up technical assistance. Within the context of a randomized wait-list controlled trial, team members who were the first recipients of the TIPS intervention demonstrated greater…
Somech, Lior Y.; Elizur, Yoel
2012-01-01
Objective: To evaluate the effectiveness and mechanisms of "Hitkashrut", a "common elements" co-parent training (PT) program for early intervention with preschoolers (3-5 years of age) at risk for conduct problems (CP). Method: A randomized controlled trial with 140 participants in PT and 69 in a minimal intervention control…
Hester, Reid K.; Delaney, Harold D.; Campbell, William
2011-01-01
Objective: To evaluate the effectiveness of a web-based protocol, ModerateDrinking.com (MD; "www.moderatedrinking.com") combined with use of the online resources of Moderation Management (MM; "www.moderation.org") as opposed to the use of the online resources of MM alone. Method: We randomly assigned 80 problem drinkers to…
Maaskant, A.M.; van Rooij, F.B.; Overbeek, G.J.; Oort, F.J.; Hermanns, J.M.A.
2016-01-01
The present randomized controlled trial examined the four months follow-up effectiveness of Parent Management Training Oregon (PMTO) for parents with foster children (aged 4–12) with severe externalizing behavior problems in long-term foster care arrangements. The aim of PMTO, a relative long and in
Rossi, A
1996-01-01
We present a generalization of the resonant neutrino conversion in matter, including a random component in the matter density profile. The study is focused on the effect of such matter perturbations upon both large and small mixing angle MSW solutions to the solar neutrino problem. This is carried out both for the active-active \
Choreographies : using Constraints to Satisfy Service Requests
Lazovik, Alexander; Aiello, Marco; Gennari, Rosella
2006-01-01
Interacting with a web service enabled marketplace to achieve a complex task involves sequencing a set of individual service operations, gathering information from the services, and making choices. In the context of choreographies of web services, we propose to encode the problem of issuing requests
Finite-temperature perturbation theory for the random directed polymer problem
Korshunov, S. E., E-mail: dimagesh@phys.ethz.ch [Russian Academy of Sciences, Landau Institute for Theoretical Physics (Russian Federation); Geshkenbein, V. B.; Blatter, G. [Theoretische Physik (Switzerland)
2013-09-15
We study the random directed polymer problem-the short-scale behavior of an elastic string (or polymer) in one transverse dimension subject to a disorder potential and finite temperature fluctuations. We are interested in the polymer short-scale wandering expressed through the displacement correlator Left-Pointing-Angle-Bracket [{delta}u(X)]{sup 2} Right-Pointing-Angle-Bracket , with {delta}u(X) being the difference in the displacements at two points separated by a distance X. While this object can be calculated at short scales using the perturbation theory in higher dimensions d > 2, this approach becomes ill-defined and the problem turns out to be nonperturbative in the lower dimensions and for an infinite-length polymer. In order to make progress, we redefine the task and analyze the wandering of a string of a finite length L. At zero temperature, we find that the displacement fluctuations Left-Pointing-Angle-Bracket [{delta}u(X)]{sup 2} Right-Pointing-Angle-Bracket {proportional_to} LX{sup 2} depend on L and scale with the square of the segment length X, which differs from a straightforward Larkin-type scaling. The result is best understood in terms of a typical squared angle Left-Pointing-Angle-Bracket {alpha}{sup 2} Right-Pointing-Angle-Bracket {proportional_to} L, where {alpha} = {partial_derivative}{sub x}u, from which the displacement scaling for the segment X follows naturally, Left-Pointing-Angle-Bracket [{delta}u(X)]{sup 2} Right-Pointing-Angle-Bracket {proportional_to} Left-Pointing-Angle-Bracket {alpha}{sup 2} Right-Pointing-Angle-Bracket X{sup 2}. At high temperatures, thermal fluctuations smear the disorder potential and the lowest-order results for disorder-induced fluctuations in both the displacement field and the angle vanish in the thermodynamic limit L {yields} {infinity}. The calculation up to the second order allows us to identify the regime of validity of the perturbative approach and provides a finite expression for the displacement
Fechtelpeter, Dennis
2011-01-01
Full Text Available Objective: To summarize the best available evidence on effectiveness of therapeutic or sport climbing in preventing or treating health problems. Methods: We searched Medline, Embase, CENTRAL, PsycINFO, PEDro, OTseeker and SportDiscus for randomized controlled trials published up to December 26, 2010. We included all trials assessing patient-relevant outcomes. Two reviewers independently selected relevant studies, assessed their methodological quality and extracted data. Quality of evidence was rated using the GRADE system. Data were entered into RevMan 5 to calculate effect sizes and 95% confidence intervals where appropriate.Results: Eligible for inclusion were four RCTs studying the effectiveness of climbing in (a geriatric patients, (b adults with multiple sclerosis, (c adults with chronic low-back pain and (d children with disabilities and poor motor function. The sample sizes ranged between 20 and 95. All trials had major methodological limitations. We found very low quality evidence that therapeutic climbing may improve activities of daily living in geriatric patients compared to physiotherapy as measured by the Barthel index (difference in mean change score: 2.32 [95%-CI: 0.45 to 4.19]. We found very low quality evidence that therapeutic climbing compared to standard exercise therapy may improve physical functioning (difference in mean change score: 16.15 [95%-CI: 4.45 to 27.85] and general physical health (13.14 [95%-CI: 3.61 to 22.67] as measured by the SF-36 in adults with chronic low back-pain. Conclusions: Evidence for the effectiveness of therapeutic climbing is limited to small trials at high risk of bias. The effects of therapeutic climbing are therefore unclear.
Critical properties of random Potts models
Kinzel, Wolfgang; Domany, Eytan
1981-04-01
The critical properties of Potts models with random bonds are considered in two dimensions. A position-space renormalization-group procedure, based on the Migdal-Kadanoff method, is developed. While all previous position-space calculations satisfied the Harris criterion and the resulting scaling relation only approximately, we found conditions under which these relations are exactly satisfied, and constructed our renormalization-group procedure accordingly. Numerical results for phase diagrams and thermodynamic functions for various random-bond Potts models are presented. In addition, some exact results obtained using a duality transformation, as well as an heuristic derivation of scaling properties that correspond to the percolation problem are given.
A New Bound for 3-Satisfiable MaxSat and its Algorithmic Application
Gutin, Gregory; Yeo, Anders
2011-01-01
Let $F$ be a CNF formula with $n$ variables and $m$ clauses. $F$ is $t$-satisfiable if for any $t$ clauses in $F$, there is a truth assignment which satisfies all of them. Lieberherr and Specker (1982) and, later, Yannakakis (1994) proved that in each 3-satisfiable CNF formula at least 2/3 of its clauses can be satisfied by a truth assignment. Yannakakis's proof utilizes the fact that 2/3 m$ is a lower bound on the expected number of clauses satisfied by a random truth assignment over a certain distribution. A CNF formula $F$ is called \\emph{expanding} if for every subset $X$ of the variables of $F$, the number of clauses containing variables of $X$ is not smaller than $|X|.$ In this paper we strengthen the 2/3 m bound by showing that, for every expanding 3-satisfiable CNF formula $F$, at least 2/3 m + \\rho n$ clauses of $F$ can be satisfied by a truth assignment, where $\\rho(>0.0019)$ is a constant. Our proof uses the probabilistic method with a sophisticated distribution for truth values. We use the bound 2...
[Intel random number generator-based true random number generator].
Huang, Feng; Shen, Hong
2004-09-01
To establish a true random number generator on the basis of certain Intel chips. The random numbers were acquired by programming using Microsoft Visual C++ 6.0 via register reading from the random number generator (RNG) unit of an Intel 815 chipset-based computer with Intel Security Driver (ISD). We tested the generator with 500 random numbers in NIST FIPS 140-1 and X(2) R-Squared test, and the result showed that the random number it generated satisfied the demand of independence and uniform distribution. We also compared the random numbers generated by Intel RNG-based true random number generator and those from the random number table statistically, by using the same amount of 7500 random numbers in the same value domain, which showed that the SD, SE and CV of Intel RNG-based random number generator were less than those of the random number table. The result of u test of two CVs revealed no significant difference between the two methods. Intel RNG-based random number generator can produce high-quality random numbers with good independence and uniform distribution, and solves some problems with random number table in acquisition of the random numbers.
SpecSatisfiabilityTool: A tool for testing the satisfiability of specifications on XML documents
Javier Albors
2015-01-01
Full Text Available We present a prototype that implements a set of logical rules to prove the satisfiability for a class of specifications on XML documents. Specifications are given by means of constrains built on Boolean XPath patterns. The main goal of this tool is to test whether a given specification is satisfiable or not, and justify the decision showing the execution history. It can also be used to test whether a given document is a model of a given specification and, as a by-product, it permits to look for all the relations (monomorphisms between two patterns and to combine patterns in different ways. The results of these operations are visually shown and therefore the tool makes these operations more understandable. The implementation of the algorithm has been written in Prolog but the prototype has a Java interface for an easy and friendly use. In this paper we show how to use this interface in order to test all the desired properties.
Bonfim Amaro Júnior
2017-01-01
Full Text Available The irregular strip packing problem (ISPP is a class of cutting and packing problem (C&P in which a set of items with arbitrary formats must be placed in a container with a variable length. The aim of this work is to minimize the area needed to accommodate the given demand. ISPP is present in various types of industries from manufacturers to exporters (e.g., shipbuilding, clothes, and glass. In this paper, we propose a parallel Biased Random-Key Genetic Algorithm (µ-BRKGA with multiple populations for the ISPP by applying a collision-free region (CFR concept as the positioning method, in order to obtain an efficient and fast layout solution. The layout problem for the proposed algorithm is represented by the placement order into the container and the corresponding orientation. In order to evaluate the proposed (µ-BRKGA algorithm, computational tests using benchmark problems were applied, analyzed, and compared with different approaches.
Fayolle, Guy; Malyshev, Vadim
2017-01-01
This monograph aims to promote original mathematical methods to determine the invariant measure of two-dimensional random walks in domains with boundaries. Such processes arise in numerous applications and are of interest in several areas of mathematical research, such as Stochastic Networks, Analytic Combinatorics, and Quantum Physics. This second edition consists of two parts. Part I is a revised upgrade of the first edition (1999), with additional recent results on the group of a random walk. The theoretical approach given therein has been developed by the authors since the early 1970s. By using Complex Function Theory, Boundary Value Problems, Riemann Surfaces, and Galois Theory, completely new methods are proposed for solving functional equations of two complex variables, which can also be applied to characterize the Transient Behavior of the walks, as well as to find explicit solutions to the one-dimensional Quantum Three-Body Problem, or to tackle a new class of Integrable Systems. Part II borrows spec...
Generalizations and Variants of the Largest Non-crossing Matching Problem in Random Bipartite Graphs
Kiwi, Marcos
2011-01-01
We are interested in the statistics of the length of the longest increasing subsequence of 2-rowed lexicographically sorted arrays chosen according to distinct families of distributions D = (D_n)_n, and when n goes to infinity. This framework encompasses well studied problems such as the so called Longest Increasing Subsequence problem, the Longest Common Subsequence problem, problems concerning directed bond percolation models, among others. We define several natural families of distinct distributions and characterize the asymptotic behavior of the expected length of a longest increasing subsequence chosen according to them. In particular, we consider generalizations to d-rowed arrays as well as symmetry restricted two-rowed arrays.
Decision Engines for Software Analysis Using Satisfiability Modulo Theories Solvers
Bjorner, Nikolaj
2010-01-01
The area of software analysis, testing and verification is now undergoing a revolution thanks to the use of automated and scalable support for logical methods. A well-recognized premise is that at the core of software analysis engines is invariably a component using logical formulas for describing states and transformations between system states. The process of using this information for discovering and checking program properties (including such important properties as safety and security) amounts to automatic theorem proving. In particular, theorem provers that directly support common software constructs offer a compelling basis. Such provers are commonly called satisfiability modulo theories (SMT) solvers. Z3 is a state-of-the-art SMT solver. It is developed at Microsoft Research. It can be used to check the satisfiability of logical formulas over one or more theories such as arithmetic, bit-vectors, lists, records and arrays. The talk describes some of the technology behind modern SMT solvers, including the solver Z3. Z3 is currently mainly targeted at solving problems that arise in software analysis and verification. It has been applied to various contexts, such as systems for dynamic symbolic simulation (Pex, SAGE, Vigilante), for program verification and extended static checking (Spec#/Boggie, VCC, HAVOC), for software model checking (Yogi, SLAM), model-based design (FORMULA), security protocol code (F7), program run-time analysis and invariant generation (VS3). We will describe how it integrates support for a variety of theories that arise naturally in the context of the applications. There are several new promising avenues and the talk will touch on some of these and the challenges related to SMT solvers. Proceedings
The cross-cultural importance of satisfying vital needs.
Alvarez, Allen Andrew A
2009-11-01
Ethical beliefs may vary across cultures but there are things that must be valued as preconditions to any cultural practice. Physical and mental abilities vital to believing, valuing and practising a culture are such preconditions and it is always important to protect them. If one is to practise a distinct culture, she must at least have these basic abilities. Access to basic healthcare is one way to ensure that vital abilities are protected. John Rawls argued that access to all-purpose primary goods must be ensured. Amartya Sen and Martha Nussbaum claim that universal capabilities are what resources are meant to enable. Len Doyal and Ian Gough identify physical health and autonomy as basic needs of every person in every culture. When we disagree on what to prioritize, when resources to satisfy competing demands are scarce, our common needs can provide a point of normative convergence. Need-based rationing, however, has been criticized for being too indeterminate to give guidance for deciding which healthcare services to prioritize and for tending to create a bottomless-pit problem. But there is a difference between needing something (first-order need) and needing to have the ability to need (second-order need). Even if we disagree about which first-order need to prioritize, we must accept the importance of satisfying our second-order need to have the ability to value things. We all have a second-order need for basic healthcare as a means to protect our vital abilities even if we differ in what our cultures consider to be particular first-order needs.
Hanisch, Charlotte; Hautmann, Christopher; Plück, Julia; Eichelberger, Ilka; Döpfner, Manfred
2014-01-01
Background: Our indicated Prevention program for preschool children with Externalizing Problem behavior (PEP) demonstrated improved parenting and child problem behavior in a randomized controlled efficacy trial and in a study with an effectiveness design. The aim of the present analysis of data from the randomized controlled trial was to identify…
Hanisch, Charlotte; Hautmann, Christopher; Plück, Julia; Eichelberger, Ilka; Döpfner, Manfred
2014-01-01
Background: Our indicated Prevention program for preschool children with Externalizing Problem behavior (PEP) demonstrated improved parenting and child problem behavior in a randomized controlled efficacy trial and in a study with an effectiveness design. The aim of the present analysis of data from the randomized controlled trial was to identify…
Reentry trajectory optimization for hypersonic vehicle satisfying complex constraints
Jiang Zhao; Rui Zhou
2013-01-01
The reentry trajectory optimization for hypersonic vehicle (HV) is a current problem of great interest. Some complex constraints, such as waypoints for reconnaissance and no-fly zones for threat avoidance, are inevitably involved in a global strike mission. Of the many direct methods, Gauss pseudospectral method (GPM) has been demonstrated as an effective tool to solve the tra-jectory optimization problem with typical constraints. However, a series of difficulties arises for complex constraints, such as the uncertainty of passage time for waypoints and the inaccuracy of approximate trajectory near no-fly zones. The research herein proposes a multi-phase technique based on the GPM to generate an optimal reentry trajectory for HV satisfying waypoint and no-fly zone constraints. Three kinds of specific breaks are introduced to divide the full trajectory into multiple phases. The continuity conditions are presented to ensure a smooth connection between each pair of phases. Numerical examples for reentry trajectory optimization in free-space flight and with complex constraints are used to demonstrate the proposed technique. Simulation results show the feasible application of multi-phase technique in reentry trajectory optimization with way-point and no-fly zone constraints.
What is satisfying about satisfying events? Testing 10 candidate psychological needs.
Sheldon, K M; Elliot, A J; Kim, Y; Kasser, T
2001-02-01
Three studies compared 10 candidate psychological needs in an attempt to determine which are truly most fundamental for humans. Participants described "most satisfying events" within their lives and then rated the salience of each of the 10 candidate needs within these events. Supporting self-determination theory postulates (Ryan & Deci, 2000)--autonomy, competence, and relatedness, were consistently among the top 4 needs, in terms of both their salience and their association with event-related affect. Self-esteem was also important, whereas self-actualization or meaning, physical thriving, popularity or influence, and money-luxury were less important. This basic pattern emerged within three different time frames and within both U.S. and South Korean samples and also within a final study that asked, "What's unsatisfying about unsatisfying events?" Implications for hierarchical theories of needs are discussed.
Freund, Kirsten S.; Lous, Jorgen
2012-01-01
Patients with many problems often face difficulties in modifying their behavior as desired. Uncovered basic needs may be an important barrier. This research tests the effect of patient-centered consultations for 20- to 44-year-old patients with multiple psychosocial and lifestyle problems. We focus on resources and barriers for obtaining…
Lower-fat menu items in restaurants satisfy customers.
Fitzpatrick, M P; Chapman, G E; Barr, S I
1997-05-01
To evaluate a restaurant-based nutrition program by measuring customer satisfaction with lower-fat menu items and assessing patrons' reactions to the program. Questionnaires to assess satisfaction with menu items were administered to patrons in eight of the nine restaurants that volunteered to participate in the nutrition program. One patron from each participating restaurant was randomly selected for a semistructured interview about nutrition programming in restaurants. Persons dining in eight participating restaurants over a 1-week period (n = 686). Independent samples t tests were used to compare respondents' satisfaction with lower-fat and regular menu items. Two-way analysis of variance tests were completed using overall satisfaction as the dependent variable and menu-item classification (ie, lower fat or regular) and one of eight other menu item and respondent characteristics as independent variables. Qualitative methods were used to analyze interview transcripts. Of 1,127 menu items rated for satisfaction, 205 were lower fat, 878 were regular, and 44 were of unknown classification. Customers were significantly more satisfied with lower-fat than with regular menu items (P satisfaction did not vary by any of the other independent variables. Interview results indicate the importance of restaurant during as an indulgent experience. High satisfaction with lower-fat menu items suggests that customers will support restaurant providing such choices. Dietitians can use these findings to encourage restaurateurs to include lower-fat choices on their menus, and to assure clients that their expectations of being indulged are not incompatible with these choices.
Exchange Rings Satisfying the n-Stable Range Condition, Ⅱ
Huanyin Chen; Fu-an Li
2003-01-01
This is a continuation of the paper [14]. It is shown that any finite subdirect product of exchange rings satisfying the n-stable range condition is still an exchange ring satisfying the n-stable range condition. Furthermore, we give necessary and sufficient conditions on matrices over an exchange ring R, under which R satisfies the n-stable range condition. This generalizes the corresponding results for unit-regular rings and the stable range one condition.
Certified Satisfiability Module Theories (SMT) Solving for System Verification
2017-01-01
CERTIFIED SATISFIABILITY MODULO THEORIES (SMT) SOLVING FOR SYSTEM VERIFICATION NEW YORK UNIVERSITY JANUARY 2017 FINAL TECHNICAL REPORT APPROVED...COVERED (From - To) AUG 2013 – JUL 2016 4. TITLE AND SUBTITLE CERTIFIED SATISFIABILITY MODULO THEORIES (SMT) SOLVING FOR SYSTEM VERIFICATION 5a...describes the results of efforts to do exactly this. CVC4, a modern, open - source solver for Satisfiability Modulo Theories (SMT), has been instrumented
On the expected value function of a simple integer recourse problem with random technology matrix
Klein Haneveld, Willem K.; van der Vlerk, Maarten H.
1994-01-01
In this paper we consider the expected value function of a stochastic simple recourse program with random technology matrix and integer variables in the second stage. Due to its separability the analysis is straightforward. Conditions for finiteness, continuity, Lipschitz continuity and
Phase Transitions for the Cavity Approach to the Clique Problem on Random Graphs
Gaudillière, Alexandre; Scoppola, Benedetto; Scoppola, Elisabetta; Viale, Massimiliano
2011-12-01
We give a rigorous proof of two phase transitions for a disordered statistical mechanics system used to define an algorithm to find large cliques inside Erdös random graphs. Such a system is a conservative probabilistic cellular automaton inspired by the cavity method originally introduced in spin glass theory.
Toneatto, Tony
2016-01-01
Empirically supported treatments for problem gambling tend to be multimodal combining cognitive, behavior and motivational interventions. Since problem gamblers often prefer briefer treatments it is important that interventions adopt strategies that are optimally effective. In this study, 99 community-recruited problem gamblers (74% male, mean age: 47.5 years) were randomized to one of four treatments: six sessions of cognitive therapy, behavior therapy, and motivational therapy or a single-session intervention. The sample was followed up for 12 months post-treatment. In both the Intent-to-Treat and Completer statistical analyses, no significant group differences on key gambling variables (i.e., frequency, expenditures, severity) were found. All four treatments showed significant improvement as a result of treatment that endured throughout the follow-up period. These results, although preliminary, suggest that very brief, single-session interventions may be as effective as longer treatments.
Maciej Goćwin
2008-01-01
Full Text Available The complexity of initial-value problems is well studied for systems of equations of first order. In this paper, we study the \\(\\varepsilon\\-complexity for initial-value problems for scalar equations of higher order. We consider two models of computation, the randomized model and the quantum model. We construct almost optimal algorithms adjusted to scalar equations of higher order, without passing to systems of first order equations. The analysis of these algorithms allows us to establish upper complexity bounds. We also show (almost matching lower complexity bounds. The \\(\\varepsilon\\-complexity in the randomized and quantum setting depends on the regularity of the right-hand side function, but is independent of the order of equation. Comparing the obtained bounds with results known in the deterministic case, we see that randomized algorithms give us a speed-up by \\(1/2\\, and quantum algorithms by \\(1\\ in the exponent. Hence, the speed-up does not depend on the order of equation, and is the same as for the systems of equations of first order. We also include results of some numerical experiments which confirm theoretical results.
Satisfying states of triangulations of a convex n-gon
Jiménez, Andrea; Loebl, Martin
2009-01-01
In this work we count the number of satisfying states of triangulations of a convex n-gon using the transfer matrix method. We show an exponential (in n) lower bound. We also give the exact formula for the number of satisfying states of a strip of triangles.
Sigmarsdóttir, Margrét; Degarmo, David S; Forgatch, Marion S; Guðmundsdóttir, Edda Vikar
2013-12-01
Findings are presented from an Icelandic randomized control trial (RCT) evaluating parent management training - Oregon model (PMTO™), a parent training intervention designed to improve parenting practices and reduce child behavior problems. In a prior report from this effectiveness study that focused on child outcomes, children in the PMTO condition showed greater reductions in reported child adjustment problems relative to the comparison group. The present report focuses on observed parenting practices as the targeted outcome, with risk by treatment moderators also tested. It was hypothesized that mothers assigned to the PMTO condition would show greater gains in pre-post parenting practices relative to controls. The sample was recruited from five municipalities throughout Iceland and included 102 participating families of children with behavior problems. Cases were referred by community professionals and randomly assigned to either PMTO (n = 51) or community services usually offered (n = 51). Child age ranged from 5 to 12 years; 73% were boys. Contrary to expectations, findings showed no main effects for changes in maternal parenting. However, evaluation of risk by treatment moderators showed greater gains in parenting practices for mothers who increased in depressed mood within the PMTO group relative to their counterparts in the comparison group. This finding suggests that PMTO prevented the expected damaging effects of depression on maternal parenting. Failure to find hypothesized main effects may indicate that there were some unobserved factors regarding the measurement and a need to further adapt the global observational procedures to Icelandic culture.
Weiss, Bahr; Han, Susan; Harris, Vicki; Catron, Thomas; Ngo, Victoria K; Caron, Annalise; Gallop, Robert; Guth, Carol
2013-12-01
Adolescent conduct problems exact serious social as well as personal costs, and effective treatments are essential. One of the most widely disseminated and effective programs for the treatment of serious conduct problems in adolescents is Multisystemic Therapy (MST). However, most evaluations of MST have involved the developers of MST. The purpose of the present study was to conduct an independent evaluation of MST, with non-court-referred adolescents with conduct problems. Participants were 164 adolescents ages 11-18 years who were recruited from self-contained behavior intervention classrooms in public schools. Adolescents and their families were randomly assigned to receive MST or services as usual. Outcome measures assessed conduct problems, school functioning, and court records of criminal behavior. Participants were followed for 18 months after baseline using parent, adolescent, and teacher reports; arrest data were collected for 2.5 years postbaseline. Two of 4 primary outcome measures focused on externalizing problems showed significant treatment effects favoring MST. Several secondary and intervention targets pertaining to family functioning and parent psychopathology showed positive effects of MST, and no negative effects were identified. Results provide some further support for the effectiveness of MST, although smaller effect sizes than previous studies also suggest the complexity of successful dissemination, particularly to non-court-referred populations.
An approximation algorithm for the Noah's Ark problem with random feature loss.
Hickey, Glenn; Blanchette, Mathieu; Carmi, Paz; Maheshwari, Anil; Zeh, Norbert
2011-01-01
The phylogenetic diversity (PD) of a set of species is a measure of their evolutionary distinctness based on a phylogenetic tree. PD is increasingly being adopted as an index of biodiversity in ecological conservation projects. The Noah's Ark Problem (NAP) is an NP-Hard optimization problem that abstracts a fundamental conservation challenge in asking to maximize the expected PD of a set of taxa given a fixed budget, where each taxon is associated with a cost of conservation and a probability of extinction. Only simplified instances of the problem, where one or more parameters are fixed as constants, have as of yet been addressed in the literature. Furthermore, it has been argued that PD is not an appropriate metric for models that allow information to be lost along paths in the tree. We therefore generalize the NAP to incorporate a proposed model of feature loss according to an exponential distribution and term this problem NAP with Loss (NAPL). In this paper, we present a pseudopolynomial time approximation scheme for NAPL.
Klein, Daniel N.; Leon, Andrew C.; Li, Chunshan; D'Zurilla, Thomas J.; Black, Sarah R.; Vivian, Dina; Dowling, Frank; Arnow, Bruce A.; Manber, Rachel; Markowitz, John C.; Kocsis, James H.
2011-01-01
Objective: Depression is associated with poor social problem solving, and psychotherapies that focus on problem-solving skills are efficacious in treating depression. We examined the associations between treatment, social problem solving, and depression in a randomized clinical trial testing the efficacy of psychotherapy augmentation for…
Klein, Daniel N.; Leon, Andrew C.; Li, Chunshan; D'Zurilla, Thomas J.; Black, Sarah R.; Vivian, Dina; Dowling, Frank; Arnow, Bruce A.; Manber, Rachel; Markowitz, John C.; Kocsis, James H.
2011-01-01
Objective: Depression is associated with poor social problem solving, and psychotherapies that focus on problem-solving skills are efficacious in treating depression. We examined the associations between treatment, social problem solving, and depression in a randomized clinical trial testing the efficacy of psychotherapy augmentation for…
Progress and problems for randomized clinical trials: from streptomycin to the era of megatrials.
Hilbrich, Lutz; Sleight, Peter
2006-09-01
Randomized clinical trials (RCTs) are the definitive contributors to evidence-based medicine. RCTs assessing serious outcomes in cardiovascular disease have grown, with 'megatrials' becoming more common with the realization that wrong conclusions resulted from random error in inadequately sized trials. Simple design and a heterogeneous patient population were early features, but multinational trials have increased in scientific, logistical, bureaucratic, regulatory, and legal complexity. These studies now exceed the financial means of academia or medical charities. Governments have left the bill with the pharmaceutical industry, encouraging a symbiosis with academics, who contribute medical and scientific expertise, and access to patients. Industry provides pharmacological, pharmaceutical, technical and regulatory know-how, good clinical practice expertise, and legal assistance during the trial. Study supervision is then in the hands of an independent steering committee and associated subcommittees, until appropriate dissemination of results. Prospectively defined interaction with the sponsor facilitates unbiased design and conduct, but arrangements need careful implementation to avoid conflicts of interest. The patient is protected by a strong data safety monitoring board that is wholly independent. Megatrials are under threat from over-regulation, increasing costs, and difficulties in execution. These issues merit urgent public and political education and debate.
A New Fuzzy Set Theory Satisfying All Classical Set Formulas
Qing-Shi Gao; Xiao-Yu Gao; Yue Hu
2009-01-01
A new fuzzy set theory, C-fuzzy set theory, is introduced in this paper. It is a particular case of the classical set theory and satisfies all formulas of the classical set theory. To add a limitation to C-fuzzy set system, in which all fuzzy sets must be "non-uniform inclusive" to each other, then it forms a family of sub-systems, the Z-fuzzy set family. It can be proved that the Z0-fuzzy set system, one of Z-fuzzy set systems, is equivalent to Zadeh's fuzzy set system. Analysis shows that 1) Zadeh's fuzzy set system defines the relations A = B and A ∈B between two fuzzy sets A and B as "Vu e U,(u A E (u)=μB(U))" and "Au ∈ U, (μA(U) ≤μB(μ))" respectively is inappropriate, because it makes all fuzzy sets be "non-uniformly inclusive"; 2) it is also inappropriate to define two fuzzy sets' union and intersection operations as the max and rain of their grades of membership, because this prevents fuzzy set's ability to correctly reflect different kinds of fuzzy phenomenon in the natural world. Then it has to work around the problem by invent unnatural functions that are hard to understand, such as augmenting max and min for union and intersection to min{a + b, 1} and max{a + b - 1, 0}, but these functions are incorrect on inclusive case. If both pairs of definitions are used together, not only are they unnatural, but also they are still unable to cover all possible set relationships in the natural world; and 3) it is incorrect to define the set complement as 1 -μA(μ), because it can be proved that set complement cannot exist in Zadeh's fuzzy set, and it causes confusion in logic and thinking. And it is seriously mistaken to believe that logics of fuzzy sets necessarily go against classical and normal thinking, logic, and conception. The C-fuzzy set theory proposed in this paper overcomes all of the above errors and shortcomings, and more reasonably reflects fuzzy phenomenon in the natural world. It satisfies all relations, formulas, and operations of the
Reflected BSDEs with Random Default Time and Related Mixed Optimal Stopping-control Problems
Dong-mei Guo; Xiao-ming Xu
2013-01-01
In this paper we study the one-dimensional reflected backward stochastic differential equations which are driven by Brownian motion as well as a mutually independent martingale appearing in a defaultable setting.Using a penalization method,we prove the existence and uniqueness of the solutions to these equations.As an application,we show that under proper assumptions the solution of the reflected equation is the value of the related mixed optimal stopping-control problem.
Semi-random simulation method for calculating 3-D radiation transfer problems in cavity
冯庭桂; 赖东显
1996-01-01
One of the most important issues in inertial confinement fusion (ICF) is to study the uniformity of the radiation field around the implosion pellet containing fuel.To this end,a numerical method linking Monte Carlo with iteration method is presented for calculating the radiation transfer problems in a cavity.The detail of the calculation scheme is described and some numerical examples are also given.
Cerrito, Serenella; David, Amelie; Goranko, Valentin
2014-01-01
We develop a sound, complete and practically implementable tableaux-based decision method for constructive satisfiability testing and model synthesis in the fragment ATL+ of the full Alternating time temporal logic ATL∗. The method extends in an essential way a previously developed tableaux......-based decision method for ATL and works in 2EXPTIME, which is the optimal worst case complexity of the satisfiability problem for ATL+. We also discuss how suitable parameterizations and syntactic restrictions on the class of input ATL+ formulae can reduce the complexity of the satisfiability problem....
On $\\gamma$-vectors satisfying the Kruskal-Katona inequalities
Nevo, Eran
2009-01-01
We present examples of flag homology spheres whose $\\gamma$-vectors satisfy the Kruskal-Katona inequalities. This includes several families of well-studied simplicial complexes, including Coxeter complexes and the simplicial complexes dual to the associahedron and to the cyclohedron. In another direction, we show that if a flag $(d-1)$-sphere has at most $2d+2$ vertices its $\\gamma$-vector satisfies the Kruskal-Katona inequalities. We conjecture that if $\\Delta$ is a flag homology sphere then $\\gamma(\\Delta)$ satisfies the Kruskal-Katona inequalities. This conjecture is a significant refinement of Gal's conjecture, which asserts that such $\\gamma$-vectors are nonnegative.
A surface-scattering model satisfying energy conservation and reciprocity
Sasihithlu, Karthik; Hugonin, Jean-Paul; Greffet, Jean-Jacques
2015-01-01
In order for surface scattering models to be accurate they must necessarily satisfy energy conservation and reciprocity principles. Roughness scattering models based on Kirchoff's approximation or perturbation theory do not satisfy these criteria in all frequency ranges. Here we present a surface scattering model based on analysis of scattering from a layer of particles on top of a substrate in the dipole approximation which satisfies both energy conservation and reciprocity and is thus accurate in all frequency ranges. The model takes into account the absorption in the substrate induced by the particles but does not take into account the near-field interactions between the particles.
Satisfiability and reasoning mechanism of terminological cycles in description logic νL
WANG Ju; JIANG YunCheng; SHEN YuMing
2008-01-01
The current research works and the existing problems of terminological cycles in description logics are analyzed in this paper. Referring to the works of Baader F and Nebel B, we aim in a new direction. Firstly, description logic vL, is defined, and the description graphs GT and GJ are redefined. A syntax condition for the satisfi-ability of membership relation is given. By using this syntax condition, we prove the following: The subsumption reasoning in vL with respect to gfp-model, Ifp-model and descriptive model is polynomial.
Nobili, Alessandro; Riva, Emma; Tettamanti, Mauro; Lucca, Ugo; Liscio, Mariarosaria; Petrucci, Bianca; Porro, Gabriella Salvini
2004-01-01
The objective was to assess the effect of a structured intervention on caregiver stress and the institutionalization rate of patients with dementia and problem behaviors. Caregivers contacting the Federazione Alzheimer Italia (AI) to receive help, advice, or information in relation to problem behaviors of outpatients were enrolled. Eligible caregiver-patient dyads were randomized to receive either a structured intervention or the counseling AI usually provides (control group). After basal assessment, families were reassessed at 6 and 12 months. Problem behavior (particularly agitation) was the only variable significantly correlated (P = 0.006) with the baseline caregivers' stress score. Thirty-nine families completed the 12-month follow-up; the mean problem behavior score was significantly lower in the intervention than the control group (p < 0.03); the time needed for care of the patient increased by 0.5 +/- 9.7 hours/day in the control group and decreased by 0.3 +/- 4.1 in the intervention group (p = 0.4, Wilcoxon test). The main determinant of institutionalization seemed to be the level of caregiver stress (p = 0.03). In patients of the intervention group, there was a significant reduction in the frequency of delusions. This pilot study suggests that caregiver stress is relieved by a structured intervention. The number of families lost to follow-up, the relatively short duration of the study, and the ceiling effect due to the severity of the clinical characteristics of patients probably all partly dilute the observed findings.
Silverstein, Michael; Feinberg, Emily; Cabral, Howard; Sauder, Sara; Egbert, Lucia; Schainker, Elisabeth; Kamholz, Karen; Hegel, Mark; Beardslee, William
2011-08-01
We sought to assess the feasibility and document key study processes of a problem-solving intervention to prevent depression among low-income mothers of preterm infants. A randomized controlled pilot trial (n = 50) of problem-solving education (PSE) was conducted. We assessed intervention provider training and fidelity; recruitment and retention of subjects; intervention acceptability; and investigators' ability to conduct monthly outcome assessments, from which we could obtain empirical estimates of depression symptoms, stress, and functioning over 6 months. Four of four bachelor-level providers were able to deliver PSE appropriately with standardized subjects within 4 weeks of training. Of 12 randomly audited PSE sessions with actual subjects, all met treatment fidelity criteria. Nineteen of 25 PSE subjects (76%) received full four-session courses; no subjects reported negative experiences with PSE. Eighty-eight percent of scheduled follow-up assessments were completed. Forty-four percent of control group mothers experienced an episode of moderately severe depression symptoms over the follow-up period, compared to 24% of PSE mothers. Control mothers experienced an average 1.19 symptomatic episodes over the 6 months of follow-up, compared to 0.52 among PSE mothers. PSE appears feasible and may be a promising strategy to prevent depression among mothers of preterm infants.
Sandoval, Luis R; Buckey, Jay C; Ainslie, Ricardo; Tombari, Martin; Stone, William; Hegel, Mark T
2017-05-01
This study evaluated the efficacy of an interactive media-based, computer-delivered depression treatment program (imbPST) compared to a no-treatment control condition (NTC) in a parallel-group, randomized, controlled trial conducted in an outpatient psychiatric research clinic. 45 adult participants with major depressive disorder or dysthymia were randomized to receive either 6 weekly sessions of imbPST or no treatment (No Treatment Control; NTC). The primary outcome measure was the Beck Depression Inventory II (BDI-II). There was a significant Group x Time interaction effect [F (1.73, 43)= 58.78; p<.001; η2=.58, Cohens d=1.94], such that the patients receiving imbPST had a significantly greater reduction in depressive symptoms compared to the patients in the NTC condition. Participants in the imbPST group improved their depression symptoms significantly from moderate (BDI-II=21.9±4.20) to mild levels of depression (BDI-II=17.9±4.0) after receiving 3 weekly sessions of imbPST (p<0.001), and progressed to still milder levels of depression after six weekly sessions (BDI-II=14.5±3.7, p<0.001). NTC participants showed no significant reduction in BDI-II scores (BDI-II=21.8±4.2 pre, BDI-II=21.5±5.2 post, N.S.). Additionally, 40% of the imbPST group showed a clinically significant and reliable change in depression levels while none of the NTC group met this criterion. imbPST participants rated the program highly usable on the system usability scale (SUS) after the first session (SUS Session 1=74.6±7.2) and usability scores increased significantly by the last session (SUS Session 6=85.4±5.6). We conclude that imbPST is an effective, engaging, and easily used depression treatment program that warrants further evaluation with heterogeneous depressed populations in a stand-alone, self-administered fashion. Copyright © 2016. Published by Elsevier Ltd.
Random Walks, Electric Networks and The Transience Class problem of Sandpiles
Choure, Ayush
2011-01-01
The Abelian Sandpile Model is a discrete diffusion process defined on graphs (Dhar \\cite{DD90}, Dhar et al. \\cite{DD95}) which serves as the standard model of \\textit{self-organized criticality}. The transience class of a sandpile is defined as the maximum number of particles that can be added without making the system recurrent (\\cite{BT05}). We develop the theory of discrete diffusions in contrast to continuous harmonic functions on graphs and establish deep connections between standard results in the study of random walks on graphs and sandpiles on graphs. Using this connection and building other necessary machinery we improve the main result of Babai and Gorodezky (SODA 2007,\\cite{LB07}) of the bound on the transience class of an $n \\times n$ grid, from $O(n^{30})$ to $O(n^{7})$. Proving that the transience class is small validates the general notion that for most natural phenomenon, the time during which the system is transient is small. In addition, we use the machinery developed to prove a number of au...
Ye, Chenglin; Giangregorio, Lora; Holbrook, Anne; Pullenayegum, Eleanor; Goldsmith, Charlie H; Thabane, Lehana
2011-05-01
It is not uncommon for a participant to withdraw from a randomized controlled trial (RCT). The withdrawal of a participant results in missing data and the potential for withdrawal bias. Data withdrawal, or a request from a participant to withdraw all of their previously collected data from a study, is particularly problematic because it leaves little opportunity to characterize or statistically address those that have withdrawn to minimize withdrawal bias. The aim of this commentary is to (1) provide a synthesis of available information on the ethical and methodological issues related to data withdrawal in RCTs and (2) provide some suggestions on how to minimize the impact of data withdrawal during the execution or analysis phases of an RCT. We searched PubMed, EMBASE and JSTOR for published articles on data withdrawal. In addition, we used internet sources as an additional tool to identify content on data withdrawal from research ethics guidelines, legislation, research ethics boards, funding agencies, professional organizations and researchers. We did not find any definitive guidelines for dealing with data withdrawal. We propose recommendations for minimizing the occurrence of data withdrawal, including explicit and clear descriptions in consent forms of how data will be handled after participant withdrawal. We also suggest using imputation techniques to deal with the missing data during analysis. The current commentary can be used to minimize the impact of data withdrawal in RCTs. Copyright © 2011 Elsevier Inc. All rights reserved.
Groups Satisfying the Maximal Condition on Non-modular Subgroups
Maria De Falco; Carmela Musella
2005-01-01
In this paper, (generalized) soluble groups for which the set of non-modular subgroups verifies the maximal condition and groups for which the set of non-permutable subgroups satisfies the same property are classified.
Exchange Rings Satisfying the n-Stable Range Condition, I
Huanyin Chen; Fu-an Li
2002-01-01
We give some necessary and sufficient conditions on an exchange ring R, under which R satisfies the n-stable range condition. We also prove that every simple separative exchange ring with finite stable range must have stable range one.
Paschall, Mallie J.; Antin, Tamar; Ringwalt, Christopher L.; Saltz, Robert F.
2011-01-01
Objective: AlcoholEdu for College is a 2- to 3-hour online course for incoming college freshmen. This study was the first multicampus trial to examine effects of AlcoholEdu for College on alcohol-related problems among freshmen. Method: Thirty universi participated in the study. Fifteen were randomly assigned to receive AlcoholEdu, and the other 15 were assigned to the control condition. AlcoholEdu was implemented by intervention schools during the summer and/or fall semester. Cross-sectional surveys of freshmen were conducted at each university beginning before the intervention in spring 2008/2009; post-intervention surveys were administered in fall 2008/2009 and spring 2009/2010. The surveys included questions about the past-30-day frequency of 28 alcohol-related problems, from which we created indices for the total number of problems and problems in seven domains: physiological, academic, social, driving under the influence/riding with drinking drivers, aggression, sexual risk taking, and victimization. Multilevel Poisson regression analyses were conducted to examine intent-to-treat and dosage effects of AlcoholEdu for College on these outcomes. Results: Multilevel intent-to-treat analyses indicated significant reductions in the risk for past-30-day alcohol problems in general and problems in the physiological, social, and victimization domains during the fall semester immediately after completion of the course. However, these effects did not persist in the spring semester. Additional analyses suggested stronger AlcoholEdu effects on these outcomes at colleges with higher rates of student course completion. No AlcoholEdu effects were observed for alcohol-related problems in the other four domains. Conclusions: AlcoholEdu for College appears to have beneficial short-term effects on victimization and the most common types of alcohol-related problems among freshmen. Universities may benefit the most by mandating AlcoholEdu for College for all incoming freshmen and
Chiu, Singa Wang; Lin, Hong-Dar; Song, Ming-Syuan; Chen, Hsin-Mei; Chiu, Yuan-Shyi P
2015-01-01
In real supply chain environments, the discontinuous multidelivery policy is often used when finished products need to be transported to retailers or customers outside the production units. To address this real-life production-shipment situation, this study extends recent work using an economic production quantity- (EPQ-) based inventory model with a continuous inventory issuing policy, defective items, and machine breakdown by incorporating a multiple delivery policy into the model to replace the continuous policy and investigates the effect on the optimal run time decision for this specific EPQ model. Next, we further expand the scope of the problem to combine the retailer's stock holding cost into our study. This enhanced EPQ-based model can be used to reflect the situation found in contemporary manufacturing firms in which finished products are delivered to the producer's own retail stores and stocked there for sale. A second model is developed and studied. With the help of mathematical modeling and optimization techniques, the optimal run times that minimize the expected total system costs comprising costs incurred in production units, transportation, and retail stores are derived, for both models. Numerical examples are provided to demonstrate the applicability of our research results.
Gardner, Frances; Shaw, Daniel S; Dishion, Thomas J; Burton, Jennifer; Supplee, Lauren
2007-09-01
Despite knowledge of early pathways to conduct problems, few preventive interventions are specifically designed to modify disruptive behavior in toddlerhood. One potential prevention target is proactive and positive parenting, which is associated with reduced risk of conduct problems in preschoolers. This randomized trial with 120 low-income 2-year-old boys examined whether a brief family-centered intervention that reduces disruptive behavior (D. Shaw, T. Dishion, L. Supplee, F. Gardner, & K. Arnds, 2006) also leads to increases in proactive and positive parenting. It also explored whether change in parenting predicts change in disruptive behavior. In the intervention group, proactive and positive parenting skills increased among parents of 3-year-olds. Change in proactive and positive parenting of 2- to 3-year-old toddlers correlated with change in child disruptive behavior, although the mediation effect of positive parenting was of only borderline significance. Findings suggest that even within a brief and multifaceted preventive intervention, change in proactive parenting skills contributes modestly but significantly to change in child problem behavior.
Khushbu Rani
2016-03-01
Full Text Available Introduction: Menstrual disorders are common problems among women in the reproductive age group. Yuga interventions may decrease the physical and psychological problems related to menstrual disorders. The present study was aimed to assess the effect of Yoga Nidra on psychological problems in patients with menstrual disorders. Methods: A total number of 100 women recruited from the department of obstetrics and gynecology and were then randomly allocated into two groups: a intervention received yogic intervention and medication for 6 month, and b control group received no yogic intervention and they only received prescribed medication. Psychological General Well-Being Index (PGWBI and hormonal profile were assessed at the time of before and after six months on both groups. Results: The mean score of anxiety, depression, positive well-being, general health, and vitality scores, as well as hormonal levels, in posttest were significantly different in intervention group as compared with pretest. But there was no significant difference in control group. Conclusion: Yoga Nidra can be a successful therapy to overcome the psychiatric morbidity associated with menstrual irregularities. Therefore, Yogic relaxation training (Yoga Nidra could be prescribed as an adjunct to conventional drug therapy for menstrual dysfunction.
Pfeiffer, Klaus; Beische, Denis; Hautzinger, Martin; Berry, Jack W; Wengert, Julia; Hoffrichter, Ruth; Becker, Clemens; van Schayck, Rudolf; Elliott, Timothy R
2014-08-01
Intervention trials for stroke caregivers after the early poststroke period are lacking. To address this gap, we examined the effectiveness of a problem-solving intervention (PSI) for stroke caregivers who provided care for at least 6 months and who experienced significant strain in their role. One hundred twenty-two family caregivers (age = 66.2 years, 77.9% female) were randomly allocated to a PSI or control group. The PSI was composed of 2 home visits and 18 telephone calls delivered over a 3-month intensive intervention and a 9-month maintenance period. PSI and control groups received monthly information letters in addition to usual care. Primary caregiver outcomes were depressive symptoms (measure: Center for Epidemiologic Studies-Depression Scale) and sense of competence (measure: Sense of Competence Questionnaire). In covariance analyses, caregivers of the PSI group showed significantly lower levels of depressive symptoms after 3 months (p caregiver social-problem-solving abilities. Although beneficial effects were observed among caregivers in the PSI group, the lack of effects on problem-solving abilities implies other characteristics of the intervention might account for these benefits. The relative intensity and therapeutic contact during the first 3 months of the intervention may be particularly helpful to caregivers of stroke survivors. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Yekini Shehu
2010-01-01
real Banach space which is also uniformly smooth using the properties of generalized f-projection operator. Using this result, we discuss strong convergence theorem concerning general H-monotone mappings and system of generalized mixed equilibrium problems in Banach spaces. Our results extend many known recent results in the literature.
Levin, Michael E; Haeger, Jack A; Pierce, Benjamin G; Twohig, Michael P
2016-07-20
There are significant challenges in addressing the mental health needs of college students. The current study tested an acceptance and commitment therapy (ACT), web-based self-help program to treat a broad range of psychological problems students struggle with. A sample of 79 college students was randomized to web-based ACT or a waitlist condition, with assessments at baseline and posttreatment. Results indicated adequate acceptability and program engagement for the ACT website. Relative to waitlist, participants receiving ACT improved on overall distress, general anxiety, social anxiety, depression, academic concerns, and positive mental health. There were no between-group effects on eating concerns, alcohol use, or hostility, or on some key ACT process of change measures. ACT participants improved more on mindful acceptance and obstruction to valued living, both of which mediated treatment outcomes. Results are discussed in the context of lessons learned with the website prototype, and areas for further research are presented. © The Author(s) 2016.
Palermo, Tonya M; Law, Emily F; Bromberg, Maggie; Fales, Jessica; Eccleston, Christopher; Wilson, Anna C
2016-06-01
This pilot randomized controlled trial aimed to determine the feasibility, acceptability, and preliminary efficacy of parental problem-solving skills training (PSST) compared with treatment as usual on improving parental mental health symptoms, physical health and well-being, and parenting behaviors. Effects of parent PSST on child outcomes (pain, emotional, and physical functioning) were also examined. Participants included 61 parents of children aged 10 to 17 years with chronic pain randomized to PSST (n = 31) or treatment as usual (n = 30) groups. Parents receiving PSST participated in 4 to 6 individual sessions of training in problem-solving skills. Outcomes were assessed at pretreatment, immediately after treatment, and at a 3-month follow-up. Feasibility was determined by therapy session attendance, therapist ratings, and parent treatment acceptability ratings. Feasibility of PSST delivery in this population was demonstrated by high compliance with therapy attendance, excellent retention, high therapist ratings of treatment engagement, and high parent ratings of treatment acceptability. PSST was associated with posttreatment improvements in parental depression (d = -0.68), general mental health (d = 0.64), and pain catastrophizing (d = -0.48), as well as in child depression (d = -0.49), child general anxiety (d = -0.56), and child pain-specific anxiety (d = -0.82). Several effects were maintained at the 3-month follow-up. Findings demonstrate that PSST is feasible and acceptable to parents of youths with chronic pain. Treatment outcome analyses show promising but mixed patterns of effects of PSST on parent and child mental health outcomes. Further rigorous trials of PSST are needed to extend these pilot results.
Random fixed points and random differential inclusions
Nikolaos S. Papageorgiou
1988-01-01
Full Text Available In this paper, first, we study random best approximations to random sets, using fixed point techniques, obtaining this way stochastic analogues of earlier deterministic results by Browder-Petryshyn, KyFan and Reich. Then we prove two fixed point theorems for random multifunctions with stochastic domain that satisfy certain tangential conditions. Finally we consider a random differential inclusion with upper semicontinuous orientor field and establish the existence of random solutions.
Weight hierarchies of linear codes satisfying the almost chain condition
无
2003-01-01
The weight hierarchy of a linear [n, k; q] code C over GF(q) is the sequence (d1, d2,…,dk) where dr is the size of the smallest support of an r-dimensional subcode of C. An [n, k; q] codehas dimension r and support of size dr for all r. Further, C satisfies the almost chain condition ifit does not satisfy the chain condition, but there exist subcodes Dr of dimension r and support offor a sequence to be the weight hierarchy of a code satisfying the almost chain condition is given.Further, explicit constructions of such codes are given, showing that in almost all cases, the necessaryconditions are also sufficient.
Rochman, Auliya Noor; Prasetyo, Hari; Nugroho, Munajat Tri
2017-06-01
Vehicle Routing Problem (VRP) often occurs when the manufacturers need to distribute their product to some customers/outlets. The distribution process is typically restricted by the capacity of the vehicle and the working hours at the distributor. This type of VRP is also known as Capacitated Vehicle Routing Problem with Time Windows (CVRPTW). A Biased Random Key Genetic Algorithm (BRKGA) was designed and coded in MATLAB to solve the CVRPTW case of soft drink distribution. The standard BRKGA was then modified by applying chromosome insertion into the initial population and defining chromosome gender for parent undergoing crossover operation. The performance of the established algorithms was then compared to a heuristic procedure for solving a soft drink distribution. Some findings are revealed (1) the total distribution cost of BRKGA with insertion (BRKGA-I) results in a cost saving of 39% compared to the total cost of heuristic method, (2) BRKGA with the gender selection (BRKGA-GS) could further improve the performance of the heuristic method. However, the BRKGA-GS tends to yield worse results compared to that obtained from the standard BRKGA.
Computational Hardness of Enumerating Satisfying Spin-Assignments in Triangulations
Jiménez, Andrea
2011-01-01
Satisfying spin-assignments in triangulations of a surface are states of minimum energy of the antiferromagnetic Ising model on triangulations which correspond (via geometric duality) to perfect matchings in cubic bridgeless graphs. In this work we show that it is NP-complete to decide whether or not a surface triangulation admits a satisfying spin-assignment, and that it is #P-complete to determine the number of such assignments. Both results are derived via an elaborate (and atypical) reduction that maps a Boolean formula in 3-conjunctive normal form into a triangulation of an orientable closed surface.
Visser, Marieke M; Heijenbrok-Kal, Majanka H; Van't Spijker, Adriaan; Lannoo, Engelien; Busschbach, Jan J V; Ribbers, Gerard M
2016-01-01
This study investigated whether problem-solving therapy (PST) is an effective group intervention for improving coping strategy and health-related quality of life (HRQoL) in patients with stroke. In this multicenter randomized controlled trial, the intervention group received PST as add-on to standard outpatient rehabilitation, the control group received outpatient rehabilitation only. Measurements were performed at baseline, directly after the intervention, and 6 and 12 months later. Data were analyzed using linear-mixed models. Primary outcomes were task-oriented coping as measured by the Coping Inventory for Stressful Situations and psychosocial HRQoL as measured by the Stroke-Specific Quality of Life Scale. Secondary outcomes were the EuroQol EQ-5D-5L utility score, emotion-oriented and avoidant coping as measured by the Coping Inventory for Stressful Situations, problem-solving skills as measured by the Social Problem Solving Inventory-Revised, and depression as measured by the Center for Epidemiological Studies Depression Scale. Included were 166 patients with stroke, mean age 53.06 years (SD, 10.19), 53% men, median time poststroke 7.29 months (interquartile range, 4.90-10.61 months). Six months post intervention, the PST group showed significant improvement when compared with the control group in task-oriented coping (P=0.008), but not stroke-specific psychosocial HRQoL. Furthermore, avoidant coping (P=0.039) and the utility value for general HRQoL (P=0.034) improved more in the PST group than in the control after 6 months. PST seems to improve task-oriented coping but not disease-specific psychosocial HRQoL after stroke >6-month follow-up. Furthermore, we found indications that PST may improve generic HRQoL recovery and avoidant coping. URL: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2509. Unique identifier: CNTR2509. © 2015 American Heart Association, Inc.
How satisfying is rural life? Fact and value
R. Veenhoven (Ruut)
1994-01-01
textabstractABSTRACT It is widely believed that life in the country is more satisfying than life in the city. This belief is propagated in romantic arts as well as in some social scientific theories. The belief is firmly rooted in public opinion, especially in the most urbanized parts of the world.
How satisfying is rural life? Fact and value
R. Veenhoven (Ruut)
1994-01-01
textabstractABSTRACT It is widely believed that life in the country is more satisfying than life in the city. This belief is propagated in romantic arts as well as in some social scientific theories. The belief is firmly rooted in public opinion, especially in the most urbanized parts of the world.
10 CFR 490.202 - Acquisitions satisfying the mandate.
2010-01-01
....202 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Mandatory State Fleet Program § 490.202 Acquisitions satisfying the mandate. The following actions within a model... operate on alternative fuels within four months after the vehicle is acquired for a State fleet; and...
Identifying Satisfied/Dissatisfied Service Encounters in Higher Education
Chahal, Hardeep; Devi, Pinkey
2013-01-01
Purpose: This paper seeks to explore satisfactory and dissatisfactory service encounters in higher education. Design/methodology/approach: The data are collected through the well established critical incident technique (CIT) method. All the satisfied and dissatisfied critical incidents are then grouped on the basis of Bitner et al.'s…
Using a satisfiability solver to identify deterministic finite state automata
Heule, M.J.H.; Verwer, S.
2009-01-01
We present an exact algorithm for identification of deterministic finite automata (DFA) which is based on satisfiability (SAT) solvers. Despite the size of the low level SAT representation, our approach seems to be competitive with alternative techniques. Our contributions are threefold: First, we p
Anatomy of Alternating Quantifier Satisfiability (Work in progress)
Dung, Phan Anh; Bjørner, Nikolaj; Monniaux, David
We report on work in progress to generalize an algorithm recently introduced in [10] for checking satisfiability of formulas with quantifier alternation. The algorithm uses two auxiliary procedures: a procedure for producing a candidate formula for quantifier elimination and a procedure for elimi...
Wade, Shari L; Walz, Nicolay C; Carey, JoAnne; Williams, Kendra M; Cass, Jennifer; Herren, Luke; Mark, Erin; Yeates, Keith Owen
2010-01-01
To examine the efficacy of teen online problem solving (TOPS) in improving executive function (EF) deficits following traumatic brain injury (TBI) in adolescence. Families of adolescents (aged 11-18 years) with moderate to severe TBI were recruited from the trauma registry of 2 tertiary-care children's hospitals and then randomly assigned to receive TOPS (n = 20), a cognitive-behavioral, skill-building intervention, or access to online resources regarding TBI (Internet resource comparison; n = 21). Parent and teen reports of EF were assessed at baseline and a posttreatment follow-up (mean = 7.88 months later). Improvements in self-reported EF skills were moderated by TBI severity, with teens with severe TBI in the TOPS treatment reporting significantly greater improvements than did those with severe TBI in the Internet resource comparison. The treatment groups did not differ on parent ratings of EF at the follow up. Findings suggest that TOPS may be effective in improving EF skills among teens with severe TBI.
Rees, Gwyneth; O'Hare, Fleur; Saeed, Marian; Sudholz, Bronwyn; Sturrock, Bonnie A; Xie, Jing; Speight, Jane; Lamoureux, Ecosse L
2017-01-01
Objective To provide preliminary evidence for the impact of problem-solving therapy for diabetes (PST-D) in adults with diabetic retinopathy (DR) and diabetes distress. Research design and methods In a pilot randomized controlled trial, 40 participants with DR and diabetes distress were allocated to the PST-D or control groups. Diabetes distress (DDS), depressive symptoms (PHQ-9), self-care activities (SDSCA), and HbA1c were assessed at baseline, and 3 and 6-month follow-ups. Results At the 6-month follow-up, the PST-D group showed significant improvements relative to the control group, in ‘regimen-related distress’ (PST-D: −1.3±1.4; control: −0.4±1.1), depressive symptoms (PST-D: −4.3±6.1; control: −0.3±4.6), and HbA1c (PST-D: −1.2%±1.01; control: 0.2%±1.2%) (all ppsychological outcomes and glycemic control. A fully powered study is required to confirm these findings and examine mechanisms of change in HbA1c. Trial registration number ACTRN12616001010482; results. PMID:28243448
Muench, Frederick; van Stolk-Cooke, Katherine; Kuerbis, Alexis; Stadler, Gertraud; Baumel, Amit; Shao, Sijing; McKay, James R; Morgenstern, Jon
2017-01-01
Recent evidence suggests that text messaging may help to reduce problem drinking as an extension to in-person services, but very little is known about the effectiveness of remote messaging on problem drinking as a stand-alone intervention, or how different types of messages may improve drinking outcomes in those seeking to moderate their alcohol consumption. We conducted an exploratory, single-blind randomized controlled pilot study comparing four different types of alcohol reduction-themed text messages sent daily to weekly drink self-tracking texts in order to determine their impact on drinking outcomes over a 12-week period in 152 participants (≈ 30 per group) seeking to reduce their drinking on the internet. Messaging interventions included: weekly drink self-tracking mobile assessment texts (MA), loss-framed texts (LF), gain-framed texts (GF), static tailored texts (ST), and adaptive tailored texts (TA). Poisson and least squares regressions were used to compare differences between each active messaging group and the MA control. When adjusting for baseline drinking, participants in all messaging groups except GF significantly reduced the number of drinks consumed per week and the number of heavy drinking days compared to MA. Only the TA and GF groups were significantly different from MA in reducing the number of drinking days. While the TA group yielded the largest effect sizes on all outcome measures, there were no significant differences between active messaging groups on any outcome measure. 79.6% of individuals enrolled in the study wanted to continue receiving messages for an additional 12 weeks at the end of the study. Results of this pilot study indicate that remote automated text messages delivered daily can help adult problem drinkers reduce drinking frequency and quantity significantly more than once-a-week self-tracking messages only, and that tailored adaptive texts yield the largest effect sizes across outcomes compared to MA. Larger samples are
Satisfying the demand for financial information in public traded companies
Holm, Claus
A public traded company which wishes to comply with IAS standards and stock exchange requirements for full public disclosure of relevant information faces a major communication task. The Investor Relation policy of such a company has to satisfy a demand for financial information which seems...... and detailed information is, however, in stark contrast to reports on the demands by leading financial analysts. In the ongoing process of improving Investor Relation policies, the companies are often meet by financial analysts looking for condensed figures and tell-all financial ratios. This paper examines...... that Investor Relation policies are still made from a supply viewpoint, i.e., the perceived need for the company to provide specific information even when presenting the condensed information through key figures and financial ratios. There is no panacea in satisfying the demand for comparable financial figures....
High Quality Test Pattern Generation and Boolean Satisfiability
Eggersglüß, Stephan
2012-01-01
This book provides an overview of automatic test pattern generation (ATPG) and introduces novel techniques to complement classical ATPG, based on Boolean Satisfiability (SAT). A fast and highly fault efficient SAT-based ATPG framework is presented which is also able to generate high-quality delay tests such as robust path delay tests, as well as tests with long propagation paths to detect small delay defects. The aim of the techniques and methodologies presented in this book is to improve SAT-based ATPG, in order to make it applicable in industrial practice. Readers will learn to improve the performance and robustness of the overall test generation process, so that the ATPG algorithm reliably will generate test patterns for most targeted faults in acceptable run time to meet the high fault coverage demands of industry. The techniques and improvements presented in this book provide the following advantages: Provides a comprehensive introduction to test generation and Boolean Satisfiability (SAT); Describes a...
Does horizon entropy satisfy a Quantum Null Energy Conjecture?
Fu, Zicao
2016-01-01
A modern version of the idea that the area of event horizons gives $4G$ times an entropy is the Hubeny-Rangamani Causal Holographic Information (CHI) proposal for holographic field theories. Given a region $R$ of a holographic QFTs, CHI computes $A/4G$ on a certain cut of an event horizon in the gravitational dual. The result is naturally interpreted as a coarse-grained entropy. CHI is known to be finitely greater than the fine-grained Hubeny-Rangamani-Takayanagi (HRT) entropy when $\\partial R$ lies on a Killing horizon of the QFT spacetime, and in this context satisfies other non-trivial properties expected of an entropy. Here we present evidence that it also satisfies the quantum null energy condition (QNEC), which bounds the second derivative of the entropy of a quantum field theory on one side of a non-expanding null surface by the flux of stress-energy across the surface. In particular, we show CHI to satisfy the QNEC in 1+1 holographic CFTs when evaluated in states dual to conical defects in AdS$_3$. Th...
Cook, David A.; Thompson, Warren G.; Thomas, Kris G.; Thomas, Matthew R.
2009-01-01
Background: Adaptation to learning styles has been proposed to enhance learning. Objective: We hypothesized that learners with sensing learning style would perform better using a problem-first instructional method while intuitive learners would do better using an information-first method. Design: Randomized, controlled, crossover trial. Setting:…
Energy levels of one-dimensional systems satisfying the minimal length uncertainty relation
Bernardo, Reginald Christian S.; Esguerra, Jose Perico H.
2016-10-01
The standard approach to calculating the energy levels for quantum systems satisfying the minimal length uncertainty relation is to solve an eigenvalue problem involving a fourth- or higher-order differential equation in quasiposition space. It is shown that the problem can be reformulated so that the energy levels of these systems can be obtained by solving only a second-order quasiposition eigenvalue equation. Through this formulation the energy levels are calculated for the following potentials: particle in a box, harmonic oscillator, Pöschl-Teller well, Gaussian well, and double-Gaussian well. For the particle in a box, the second-order quasiposition eigenvalue equation is a second-order differential equation with constant coefficients. For the harmonic oscillator, Pöschl-Teller well, Gaussian well, and double-Gaussian well, a method that involves using Wronskians has been used to solve the second-order quasiposition eigenvalue equation. It is observed for all of these quantum systems that the introduction of a nonzero minimal length uncertainty induces a positive shift in the energy levels. It is shown that the calculation of energy levels in systems satisfying the minimal length uncertainty relation is not limited to a small number of problems like particle in a box and the harmonic oscillator but can be extended to a wider class of problems involving potentials such as the Pöschl-Teller and Gaussian wells.
Energy levels of one-dimensional systems satisfying the minimal length uncertainty relation
Bernardo, Reginald Christian S., E-mail: rcbernardo@nip.upd.edu.ph; Esguerra, Jose Perico H., E-mail: jesguerra@nip.upd.edu.ph
2016-10-15
The standard approach to calculating the energy levels for quantum systems satisfying the minimal length uncertainty relation is to solve an eigenvalue problem involving a fourth- or higher-order differential equation in quasiposition space. It is shown that the problem can be reformulated so that the energy levels of these systems can be obtained by solving only a second-order quasiposition eigenvalue equation. Through this formulation the energy levels are calculated for the following potentials: particle in a box, harmonic oscillator, Pöschl–Teller well, Gaussian well, and double-Gaussian well. For the particle in a box, the second-order quasiposition eigenvalue equation is a second-order differential equation with constant coefficients. For the harmonic oscillator, Pöschl–Teller well, Gaussian well, and double-Gaussian well, a method that involves using Wronskians has been used to solve the second-order quasiposition eigenvalue equation. It is observed for all of these quantum systems that the introduction of a nonzero minimal length uncertainty induces a positive shift in the energy levels. It is shown that the calculation of energy levels in systems satisfying the minimal length uncertainty relation is not limited to a small number of problems like particle in a box and the harmonic oscillator but can be extended to a wider class of problems involving potentials such as the Pöschl–Teller and Gaussian wells.
Hegel, Mark T.; Lyons, Kathleen D.; Hull, Jay G.; Kaufman, Peter; Urquhart, Laura; Li, Zhongze; Ahles, Tim A.
2010-01-01
Objective Breast cancer patients receiving adjuvant chemotherapy often experience functional effects of treatment that limit participation in life activities. The purpose of this study was to examine the feasibility of conducting a randomized controlled trial (RCT) of a novel intervention for these restrictions, determine acceptability of the intervention, and preliminarily assess its effects. Methods A pilot RCT of a telephone-delivered Problem Solving and Occupational Therapy intervention (PST-OT) to improve participation restrictions in rural breast cancer patients undergoing chemotherapy. Thirty-one participants with Stages 1-3 breast cancer were randomized to 6 weekly sessions of PST-OT (n=15) and Usual Care (n=16). The primary study outcome was the feasibility of conducting the trial. Secondary outcomes were functional, quality of life and emotional status as assessed at baseline, 6 weeks and 12 weeks. Results Of 46 patients referred 31 were enrolled (67% recruitment rate), of which 6 participants withdrew (81% retention rate). Twenty-four participants completed all study-related assessments (77%). Ninety-two percent of PST-OT participants were highly satisfied with the intervention, and 92% reported PST-OT to be helpful/very helpful for overcoming participation restrictions. Ninety-seven percent of planned PST-OT treatment sessions were completed. Completion rates for PST-OT homework tasks were high. Measures of functioning, quality of life and emotional state favored the PST-OT condition. Conclusion This pilot study suggests that an RCT of the PST-OT intervention is feasible to conduct with rural breast cancer patients undergoing adjuvant chemotherapy and that PST-OT may have positive effects on function, quality of life, and emotional state. PMID:20821373
Hegel, Mark T; Lyons, Kathleen D; Hull, Jay G; Kaufman, Peter; Urquhart, Laura; Li, Zhongze; Ahles, Tim A
2011-10-01
Breast cancer patients receiving adjuvant chemotherapy often experience functional effects of treatment that limit participation in life activities. The purpose of this study was to examine the feasibility of conducting a randomized controlled trial (RCT) of a novel intervention for these restrictions, determine acceptability of the intervention, and preliminarily assess its effects. A pilot RCT of a telephone-delivered Problem-solving and Occupational Therapy intervention (PST-OT) to improve participation restrictions in rural breast cancer patients undergoing chemotherapy. Thirty-one participants with Stages 1-3 breast cancer were randomized to 6 weekly sessions of PST-OT (n = 15) and usual care (n = 16). The primary study outcome was the feasibility of conducting the trial. Secondary outcomes were functional, quality of life and emotional status as assessed at baseline, 6 and 12 weeks. Of 46 patients referred 31 were enrolled (67% recruitment rate), of which 6 participants withdrew (81% retention rate). Twenty-four participants completed all study-related assessments (77%). Ninety-two percent of PST-OT participants were highly satisfied with the intervention, and 92% reported PST-OT to be helpful/very helpful for overcoming participation restrictions. Ninety-seven percent of planned PST-OT treatment sessions were completed. Completion rates for PST-OT homework tasks were high. Measures of functioning, quality of life, and emotional state favored the PST-OT condition. This pilot study suggests that an RCT of the PST-OT intervention is feasible to conduct with rural breast cancer patients undergoing adjuvant chemotherapy and that PST-OT may have positive effects on function, quality of life, and emotional state. 2010 John Wiley & Sons, Ltd.
Does horizon entropy satisfy a quantum null energy conjecture?
Fu, Zicao; Marolf, Donald
2016-12-01
A modern version of the idea that the area of event horizons gives 4G times an entropy is the Hubeny-Rangamani causal holographic information (CHI) proposal for holographic field theories. Given a region R of a holographic QFTs, CHI computes A/4G on a certain cut of an event horizon in the gravitational dual. The result is naturally interpreted as a coarse-grained entropy for the QFT. CHI is known to be finitely greater than the fine-grained Hubeny-Rangamani-Takayanagi (HRT) entropy when \\partial R lies on a Killing horizon of the QFT spacetime, and in this context satisfies other non-trivial properties expected of an entropy. Here we present evidence that it also satisfies the quantum null energy condition (QNEC), which bounds the second derivative of the entropy of a quantum field theory on one side of a non-expanding null surface by the flux of stress-energy across the surface. In particular, we show CHI to satisfy the QNEC in 1 + 1 holographic CFTs when evaluated in states dual to conical defects in AdS3. This surprising result further supports the idea that CHI defines a useful notion of coarse-grained holographic entropy, and suggests unprecedented bounds on the rate at which bulk horizon generators emerge from a caustic. To supplement our motivation, we include an appendix deriving a corresponding coarse-grained generalized second law for 1 + 1 holographic CFTs perturbatively coupled to dilaton gravity.
Kaplan, Sezgin; Rabadi, Ghaith
2013-01-01
This article addresses the aerial refuelling scheduling problem (ARSP), where a set of fighter jets (jobs) with certain ready times must be refuelled from tankers (machines) by their due dates; otherwise, they reach a low fuel level (deadline) incurring a high cost. ARSP is an identical parallel machine scheduling problem with release times and due date-to-deadline windows to minimize the total weighted tardiness. A simulated annealing (SA) and metaheuristic for randomized priority search (Meta-RaPS) with the newly introduced composite dispatching rule, apparent piecewise tardiness cost with ready times (APTCR), are applied to the problem. Computational experiments compared the algorithms' solutions to optimal solutions for small problems and to each other for larger problems. To obtain optimal solutions, a mixed integer program with a piecewise weighted tardiness objective function was solved for up to 12 jobs. The results show that Meta-RaPS performs better in terms of average relative error but SA is more efficient.
Fractional Stochastic Differential Equations Satisfying Fluctuation-Dissipation Theorem
Li, Lei; Liu, Jian-Guo; Lu, Jianfeng
2017-09-01
We propose in this work a fractional stochastic differential equation (FSDE) model consistent with the over-damped limit of the generalized Langevin equation model. As a result of the `fluctuation-dissipation theorem', the differential equations driven by fractional Brownian noise to model memory effects should be paired with Caputo derivatives, and this FSDE model should be understood in an integral form. We establish the existence of strong solutions for such equations and discuss the ergodicity and convergence to Gibbs measure. In the linear forcing regime, we show rigorously the algebraic convergence to Gibbs measure when the `fluctuation-dissipation theorem' is satisfied, and this verifies that satisfying `fluctuation-dissipation theorem' indeed leads to the correct physical behavior. We further discuss possible approaches to analyze the ergodicity and convergence to Gibbs measure in the nonlinear forcing regime, while leave the rigorous analysis for future works. The FSDE model proposed is suitable for systems in contact with heat bath with power-law kernel and subdiffusion behaviors.
The structure of boundary parameter property satisfying sets
Whale, B E
2010-01-01
Precise definitions of singularities in General Relativity rely on a set of curves. Many boundary constructions force a particular set of curves by virtue of the construction. The abstract boundary, however, allows the set of curves to be chosen. This set, therefore, plays a very important role in the use of the abstract boundary as the definition of a singularity or point at infinity depends on it. The sets of curves used in the abstract boundary must satisfy the boundary parameter property. This property obfuscates the construction of and relationships between these sets of curves. In this paper we lay the ground work for an analysis of these sets of curves by showing that they are in one-to-one correspondence with certain sets of inextendible curves. As an application of this result we show how the usual set operations can be extended to boundary parameter property satisfying sets of curves, allowing for their comparison. These results provide an interpretation of what information boundary parameter proper...
Leading change to create a healthy and satisfying work environment.
Sanders, Carolyn L; Krugman, Mary; Schloffman, Danielle H
2013-01-01
Nurse executives must take a leadership role in creating a healthy work environment for nurses and all disciplines. Engaging in partnerships and empowering clinical nurses to construct the solutions to barriers that may stand in the way of the goal of a satisfied and healthy workforce are important strategies toward success. This publication outlines many projects a 3-time Magnet-designated academic hospital has implemented, working with our shared leadership councils, to meet the standards for a healthy work environment. These initiatives, from the unit to the hospital level, included standardizing a culture change of uninterrupted meal breaks, the creation of intensive care unit Zen rooms, strategies to better manage increased patient volumes, best practices for facility design, enhancing physician-nurse relations, and a hospital wellness program. Data were benchmarked against national nurse and employee surveys to compare progress and report outcomes. Two important nursing organization structures that have contributed to the success of a healthy and satisfied nursing work environment include UEXCEL, a longstanding clinical nurse professional practice program, and the hospital's 11-year participation in the University HealthSystem Consortium/American Association of Colleges of Nursing National Post-Baccalaureate Nurse Residency Program. A highly engaged, well-educated, and committed nursing workforce, nurtured by a strong leadership team, has created a positive work environment characterized by low turnover and high retention.
Accelerating Activation Function for 3- Satisfiability Logic Programming
Mohd Asyraf Mansor
2016-10-01
Full Text Available This paper presents the technique for accelerating 3-Satisfiability (3-SAT logic programming in Hopfield neural network. The core impetus for this work is to integrate activation function for doing 3-SAT logic programming in Hopfield neural network as a single hybrid network. In logic programming, the activation function can be used as a dynamic post optimization paradigm to transform the activation level of a unit (neuron into an output signal. In this paper, we proposed Hyperbolic tangent activation function and Elliot symmetric activation function. Next, we compare the performance of proposed activation functions with a conventional function, namely McCu lloch-Pitts function. In this study, we evaluate the performances between these functions through computer simulations. Microsoft Visual C++ 2013 was used as a platform for training, validating and testing of the network. We restrict our analysis to 3-Satisfiability (3-SAT clauses. Moreover, evaluations are made between these activation functions to see the robustness via aspects of global solutions, global Hamming distance, and CPU time.
Klein, Daniel N.; Leon, Andrew C.; Li, Chunshan; D’Zurilla, Thomas J.; Black, Sarah R.; Vivian, Dina; Dowling, Frank; Arnow, Bruce A.; Manber, Rachel; Markowitz, John C.; Kocsis, James H.
2011-01-01
Objective Depression is associated with poor social problem-solving, and psychotherapies that focus on problem-solving skills are efficacious in treating depression. We examined the associations between treatment, social problem solving, and depression in a randomized clinical trial testing the efficacy of psychotherapy augmentation for chronically depressed patients who failed to fully respond to an initial trial of pharmacotherapy (Kocsis et al., 2009). Method Participants with chronic depression (n = 491) received Cognitive Behavioral Analysis System of Psychotherapy (CBASP), which emphasizes interpersonal problem-solving, plus medication; Brief Supportive Psychotherapy (BSP) plus medication; or medication alone for 12 weeks. Results CBASP plus pharmacotherapy was associated with significantly greater improvement in social problem solving than BSP plus pharmacotherapy, and a trend for greater improvement in problem solving than pharmacotherapy alone. In addition, change in social problem solving predicted subsequent change in depressive symptoms over time. However, the magnitude of the associations between changes in social problem solving and subsequent depressive symptoms did not differ across treatment conditions. Conclusions It does not appear that improved social problem solving is a mechanism that uniquely distinguishes CBASP from other treatment approaches. PMID:21500885
Random walks on coset spaces with applications to Furstenberg entropy
Bowen, Lewis
2010-01-01
We study the Poisson boundary of a random walk on the coset space of a random subgroup of a locally compact group whose law is conjugation-invariant. Then we construct a path of ergodic stationary actions of the free group on which the Furstenberg entropy varies continuously, thereby solving the Furstenberg entropy realization problem for free groups. This result is motivated by the general problem of understanding the structure of stationary actions and more specifically by works of Nevo and Zimmer which proved the Furstenberg entropies of stationary actions of a higher rank semisimple Lie group satisfying a certain mixing condition are restricted to a finite set.
Exact Rotating Magnetic Traversable Wormholes satisfying the Energy Conditions
Matos, Tonatiuh
2015-01-01
In this work we wonder if there is a way to generate a wormhole (WH) in nature using "normal" matter. In order to give a first answer to this question, we study a massless scalar field coupled to an electromagnetic one (dilatonic field) with an arbitrary coupling constant, as source of gravitation. We obtain an exact solution of the Einstein equations using this source that represents a magnetized rotating WH. This space-time has a naked ring singularity, probably untouchable as in \\cite{Matos:2012gj}, but otherwise regular. The WH throat lies on the disc bounded by the ring singularity, which keeps the throat open without requiring exotic matter, that means, satisfying all the energy conditions. After analyzing the geodesic motion and the tidal forces we find that a test particle can go through the WH without troubles.
Can quantum probes satisfy the weak equivalence principle?
Seveso, Luigi, E-mail: luigi.seveso@unimi.it [Quantum Technology Lab, Dipartimento di Fisica, Università degli Studi di Milano, I-20133 Milano (Italy); Paris, Matteo G.A. [Quantum Technology Lab, Dipartimento di Fisica, Università degli Studi di Milano, I-20133 Milano (Italy); INFN, Sezione di Milano, I-20133 Milano (Italy)
2017-05-15
We address the question whether quantum probes in a gravitational field can be considered as test particles obeying the weak equivalence principle (WEP). A formulation of the WEP is proposed which applies also in the quantum regime, while maintaining the physical content of its classical counterpart. Such formulation requires the introduction of a gravitational field not to modify the Fisher information about the mass of a freely-falling probe, extractable through measurements of its position. We discover that, while in a uniform field quantum probes satisfy our formulation of the WEP exactly, gravity gradients can encode nontrivial information about the particle’s mass in its wavefunction, leading to violations of the WEP. - Highlights: • Can quantum probes under gravity be approximated as test-bodies? • A formulation of the weak equivalence principle for quantum probes is proposed. • Quantum probes are found to violate it as a matter of principle.
From Satisfying to Violating the Null Energy Condition
Elder, Benjamin; Khoury, Justin
2013-01-01
We construct a theory which admits a time-dependent solution smoothly interpolating between a null energy condition (NEC)-satisfying phase at early times and a NEC-violating phase at late times. We first review earlier attempts to violate the NEC and an argument of Rubakov, presented in 1305.2614, which forbids the existence of such interpolating solutions in a single-field dilation-invariant theory. We then construct a theory which, in addition to possessing a Poincar\\'e-invariant vacuum, does admit such a solution. For a wide range of parameters, perturbations around this solution are at all times stable, comfortably subluminal and weakly-coupled. The theory requires us to explicitly break dilation-invariance, so it is unlikely that the theory is fully stable under quantum corrections, but we argue that the existence of a healthy interpolating solution is quantum-mechanically robust.
Quiet planting in the locked constraints satisfaction problems
Zdeborova, Lenka [Los Alamos National Laboratory; Krzakala, Florent [Los Alamos National Laboratory
2009-01-01
We study the planted ensemble of locked constraint satisfaction problems. We describe the connection between the random and planted ensembles. The use of the cavity method is combined with arguments from reconstruction on trees and first and second moment considerations; in particular the connection with the reconstruction on trees appears to be crucial. Our main result is the location of the hard region in the planted ensemble, thus providing hard satisfiable benchmarks. In a part of that hard region instances have with high probability a single satisfying assignment.
Random fixed points of non-self maps and random approximations
Ismat Beg
1997-01-01
Full Text Available In this paper we prove random fixed point theorems in reflexive Banach spaces for nonexpansive random operators satisfying inward or Leray-Schauder condition and establish a random approximation theorem.
Molander, Peter; Hesser, Hugo; Weineland, Sandra; Bergwall, Kajsa; Buck, Sonia; Hansson-Malmlöf, Johan; Lantz, Henning; Lunner, Thomas; Andersson, Gerhard
2015-09-01
Psychological distress and psychiatric symptoms are prevalent among people with hearing loss or other audiological conditions, but psychological interventions for these groups are rare. This article describes the study protocol for a randomized controlled trial for evaluating the effect of a psychological treatment delivered over the Internet for individuals with hearing problems and concurrent psychological distress. Participants who are significantly distressed will be randomized to either an 8-week Internet-delivered acceptance-based cognitive behavioral therapy (i.e., acceptance and commitment therapy [ACT]), or wa it-list control. We aim to include measures of distress associated with hearing difficulties, anxiety, and depression. In addition, we aim to measure acceptance associated with hearing difficulties as well as quality of life. The results of the trial may further our understanding of how to best treat people who present problems with both psychological distress and hearing in using the Internet.
The Convergence in Distribution Problems of the Random Bernstein Polynomial%随机Bernstein多项式的依分布收敛问题
于巍; 许爽爽; 姜雪
2013-01-01
利用随机的Bernstein多项式研究随机逼近问题具有一定的意义.借助弱收敛的概念,从分布函数的角度,讨论了随机Bernstein多项式依分布收敛问题.同时,与依概率收敛结果相比较,以此说明Bernstein多项式序列依分布收敛适用的范围更广.%It is very meaningful for studying the approximation problem of the random Bernstein polynomial.In this paper,the convergence in distribution problems of the random Bernstein polynomial is discussed in use of the weak convergence.Comparing with the convergence in probability,the convergence in distribution is more useful.
Wensheng Guo
Full Text Available In biological systems, the dynamic analysis method has gained increasing attention in the past decade. The Boolean network is the most common model of a genetic regulatory network. The interactions of activation and inhibition in the genetic regulatory network are modeled as a set of functions of the Boolean network, while the state transitions in the Boolean network reflect the dynamic property of a genetic regulatory network. A difficult problem for state transition analysis is the finding of attractors. In this paper, we modeled the genetic regulatory network as a Boolean network and proposed a solving algorithm to tackle the attractor finding problem. In the proposed algorithm, we partitioned the Boolean network into several blocks consisting of the strongly connected components according to their gradients, and defined the connection between blocks as decision node. Based on the solutions calculated on the decision nodes and using a satisfiability solving algorithm, we identified the attractors in the state transition graph of each block. The proposed algorithm is benchmarked on a variety of genetic regulatory networks. Compared with existing algorithms, it achieved similar performance on small test cases, and outperformed it on larger and more complex ones, which happens to be the trend of the modern genetic regulatory network. Furthermore, while the existing satisfiability-based algorithms cannot be parallelized due to their inherent algorithm design, the proposed algorithm exhibits a good scalability on parallel computing architectures.
Guo, Wensheng; Yang, Guowu; Wu, Wei; He, Lei; Sun, Mingyu
2014-01-01
In biological systems, the dynamic analysis method has gained increasing attention in the past decade. The Boolean network is the most common model of a genetic regulatory network. The interactions of activation and inhibition in the genetic regulatory network are modeled as a set of functions of the Boolean network, while the state transitions in the Boolean network reflect the dynamic property of a genetic regulatory network. A difficult problem for state transition analysis is the finding of attractors. In this paper, we modeled the genetic regulatory network as a Boolean network and proposed a solving algorithm to tackle the attractor finding problem. In the proposed algorithm, we partitioned the Boolean network into several blocks consisting of the strongly connected components according to their gradients, and defined the connection between blocks as decision node. Based on the solutions calculated on the decision nodes and using a satisfiability solving algorithm, we identified the attractors in the state transition graph of each block. The proposed algorithm is benchmarked on a variety of genetic regulatory networks. Compared with existing algorithms, it achieved similar performance on small test cases, and outperformed it on larger and more complex ones, which happens to be the trend of the modern genetic regulatory network. Furthermore, while the existing satisfiability-based algorithms cannot be parallelized due to their inherent algorithm design, the proposed algorithm exhibits a good scalability on parallel computing architectures.
Characterizing the NP-PSPACE Gap in the Satisfiability Problem for Modal Logic
2007-02-01
BEZHANISHVILI AND I. M. HODKINSON, All normal extensions of S5-squared are finitely axiomatizable, Studia Logica , 78 (2004), pp. 443–457. [3] P. BLACKBURN, M...complete, Studia Logica , 81 (2005), pp. 153–165. [11] M. C. NAGLE, The decidability of normal K5 logics, Journal of Symbolic Logic, 46 (1981), pp. 319–328
Aman, Michael G.; McDougle, Christopher J.; Scahill, Lawrence; Handen, Benjamin; Arnold, L. Eugene; Johnson, Cynthia; Stigler, Kimberly A.; Bearss, Karen; Butter, Eric; Swiezy, Naomi B.; Sukhodolsky, Denis D.; Ramadan, Yaser; Pozdol, Stacie L.; Nikolov, Roumen; Lecavalier, Luc; Kohn, Arlene E.; Koenig, Kathleen; Hollway, Jill A.; Korzekwa, Patricia; Gavaletz, Allison; Mulick, James A.; Hall, Kristy L.; Dziura, James; Ritz, Louise; Trollinger, Stacie; Yu, Sunkyung; Vitiello, Benedetto; Wagner, Ann
2009-01-01
Objective: Many children with pervasive developmental disorders (PDDs) have serious, functionally impairing behavioral problems. We tested whether combined treatment (COMB) with risperidone and parent training (PT) in behavior management is superior to medication alone (MED) in improving severe behavioral problems in children with PDDs. Method:…
Spijkers, Edwin; Jansen, Danielle; Reijneveld, Menno
2013-01-01
Background: Psychosocial problems in children have adverse effects on the children, their families, and society, thus early intervention is important. Community pediatric services offer an ideal setting to detect problem behaviour in children and provide support to parents. The objective of this stu
Satisfiability of logic programming based on radial basis function neural networks
Hamadneh, Nawaf; Sathasivam, Saratha; Tilahun, Surafel Luleseged; Choon, Ong Hong [School of Mathematical Sciences, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia)
2014-07-10
In this paper, we propose a new technique to test the Satisfiability of propositional logic programming and quantified Boolean formula problem in radial basis function neural networks. For this purpose, we built radial basis function neural networks to represent the proportional logic which has exactly three variables in each clause. We used the Prey-predator algorithm to calculate the output weights of the neural networks, while the K-means clustering algorithm is used to determine the hidden parameters (the centers and the widths). Mean of the sum squared error function is used to measure the activity of the two algorithms. We applied the developed technique with the recurrent radial basis function neural networks to represent the quantified Boolean formulas. The new technique can be applied to solve many applications such as electronic circuits and NP-complete problems.
Satisfiability of logic programming based on radial basis function neural networks
Hamadneh, Nawaf; Sathasivam, Saratha; Tilahun, Surafel Luleseged; Choon, Ong Hong
2014-07-01
In this paper, we propose a new technique to test the Satisfiability of propositional logic programming and quantified Boolean formula problem in radial basis function neural networks. For this purpose, we built radial basis function neural networks to represent the proportional logic which has exactly three variables in each clause. We used the Prey-predator algorithm to calculate the output weights of the neural networks, while the K-means clustering algorithm is used to determine the hidden parameters (the centers and the widths). Mean of the sum squared error function is used to measure the activity of the two algorithms. We applied the developed technique with the recurrent radial basis function neural networks to represent the quantified Boolean formulas. The new technique can be applied to solve many applications such as electronic circuits and NP-complete problems.
Locally manufactured wheelchairs in Tanzania - are users satisfied?
Amosun, Seyi; Ndosi, Aston; Buchanan, Helen
2016-12-01
The government of Tanzania created opportunity for the production of wheelchairs that would be appropriate to the local needs and environment. The study assessed the extent to which the wheelchairs met the activity and participation needs of the users, as well as the users' level of satisfaction with the provision, repair and maintenance of these wheelchairs. A descriptive cross-sectional analytical design was utilized to collect data through the administration of a questionnaire among 75 adult wheelchair users. Participants had used wheelchairs for an average period of 9.3 years. Most participants (61%) had sustained spinal cord injuries, and used three-wheeler chairs (76%). More than 90% reported that their wheelchairs positively influenced their activity and participation needs, and 85% were satisfied with their ability to carry out daily activities. Participants expressed satisfaction with the durability of the wheelchairs (89%), and the professional services received (71%), but not with follow-up services (77%). There was difference in satisfaction with features of 3-wheeler and 4-wheeler rigid chairs (p=0.030). The wheelchairs positively impacted participants' activity and participation needs. Participants were sat isfied with the features of the wheelchairs but not with follow-up services. The concerns of dissatisfied users should be addressed.
Are the French neurology residents satisfied with their training?
Codron, P; Roux, T; Le Guennec, L; Zuber, M
2015-11-01
There have been dramatic changes in neurology over the past decade; these advances require a constant adaptation of residents' theoretical and practical training. The French Association of Neurology Residents and the College of Neurology Teachers conducted a national survey to assess the French neurology residents' satisfaction about their training. A 16-item questionnaire was sent via e-mail to French neurology residents completing training in 2014. Data were collected and processed anonymously. Of eligible respondents, 126 returned the survey, representing approximately 40% of all the French neurology residents. Most residents (78%) rated their clinical training favorably. Seventy-two percent reported good to excellent quality teaching of neurology courses from their faculty. However, many residents (40%) felt insufficient their doctoral thesis supervision. All residents intended to enter fellowship training after their residency, and most of them (68%) planned to practice in a medical center. French neurology residents seemed satisfied with the structure and quality of their training program. However, efforts are required to improve management of the doctoral thesis and make private practice more attractive and accessible during the residency. In the future, similar surveys should be scheduled to regularly assess neurology residents' satisfaction and the impact of the forthcoming national and European reforms. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Sandwiched Rényi divergence satisfies data processing inequality
Beigi, Salman [School of Mathematics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5746, Tehran (Iran, Islamic Republic of)
2013-12-15
Sandwiched (quantum) α-Rényi divergence has been recently defined in the independent works of Wilde et al. [“Strong converse for the classical capacity of entanglement-breaking channels,” preprint http://arxiv.org/abs/arXiv:1306.1586 (2013)] and Müller-Lennert et al. [“On quantum Rényi entropies: a new definition, some properties and several conjectures,” preprint http://arxiv.org/abs/arXiv:1306.3142v1 (2013)]. This new quantum divergence has already found applications in quantum information theory. Here we further investigate properties of this new quantum divergence. In particular, we show that sandwiched α-Rényi divergence satisfies the data processing inequality for all values of α > 1. Moreover we prove that α-Holevo information, a variant of Holevo information defined in terms of sandwiched α-Rényi divergence, is super-additive. Our results are based on Hölder's inequality, the Riesz-Thorin theorem and ideas from the theory of complex interpolation. We also employ Sion's minimax theorem.
Why do even satisfied newlyweds eventually go on to divorce?
Lavner, Justin A; Bradbury, Thomas N
2012-02-01
Although divorce typically follows an extended period of unhappiness that begins early in marriage, some couples who are very happy throughout the first several years of marriage will also go on to divorce. This study aimed to identify risk factors early in marriage that distinguish initially satisfied couples who eventually divorce from those who remain married. We identified 136 couples reporting stably high levels of relationship satisfaction in the first 4 years of marriage. We compared the couples who went on to divorce by the 10-year follow-up with the couples who remained married on initial measures of commitment, observed communication, stress, and personality. Divorcing couples displayed more negative communication, emotion, and social support as newlyweds compared with couples who did not divorce. No significant differences were found in the other domains, in relationship satisfaction, or in positive behaviors. Overall, results indicate that even couples who are very successful at navigating the early years of marriage can be vulnerable to later dissolution if their interpersonal exchanges are poorly regulated. We speculate that, paradoxically, the many strengths possessed by these couples may mask their potent interpersonal liabilities, posing challenges for educational interventions designed to help these couples.
Are Emotionally Intelligent EFL Teachers More Satisfied Professionally?
Mohammad Hossein Hekmatzadeh
2016-03-01
Full Text Available Despite the fact that Intelligence Quotient (IQ is an important factor in one’s success in terms of working environment, it is believed that emotional quotient or EQ plays a more important role. With that in mind, this study investigated the relationship between emotional intelligence and job satisfaction of English as Foreign Language (EFL teachers who work at private language institutes in Iran/Shiraz. Furthermore, this study tried to answer whether there is a significant difference between emotional intelligence and job satisfaction of Iranian’s EFL teachers in terms of gender. A 90-item Bar-On questionnaire was used to measure the teachers’ emotional intelligence; also, a modified version of Karavas’s (2010 job satisfaction scale was used to see how satisfied our teachers are with their teaching career. To answer the research question, Pearson Product-Moment Correlation Coefficient statistical test was run. The results showed that there was a positive and significant correlation between emotional intelligence and job satisfaction of EFL teachers in Iran/Shiraz. Furthermore, the results revealed that there was a statistically significant difference in emotional intelligence between EFL male and female teachers, but there was no statistically significant relationship between Iranian EFL teachers’ job satisfaction in terms of gender. Based on our findings, it is suggested that some preparatory courses aiming at enhancing the important psychological traits such as emotional intelligence should be incorporated in educational programs designed for novice teachers so that it will contribute to pedagogical improvement.
David S Rebergen; David J Bruinvels; Chris M Bos; Allard J van der Beek; Willem van Mechelen
2010-01-01
...) to the Dutch guideline on the management of common mental health problems and its effect on return to work as part of the process evaluation of a trial comparing adherence to the guideline to care as usual...
Serio, Carmine; Masiello, Guido; Liuzzi, Giuliano
2016-08-20
The random projections statistical technique has been used to reduce the dimensionality of the radiance data space generated from high spectral resolution infrared observations. The mathematical inversion of the physical radiative transfer equation for geophysical parameters has been solved in this space of reduced dimensionality. The great advantage of using random projections is that they provide an unified treatment of instrument noise and forward model error, which can be comprehensively modeled with a single variance term. The result is a novel retrieval approach, which combines computational efficiency to possibly improved accuracy of the retrieval products. The novel approach has been demonstrated through application to the Infrared Atmospheric Sounding Interferometer. We have found that state-of-the-art spectroscopy and related line-mixing treatment for the ν2CO2 absorption band, i.e., the fundamental band for temperature retrieval, show an excellent consistency with satellite observations.
Satisfying patients' rights in Iran: Providing effective strategies.
Anbari, Zohreh; Mohammadi, Mehri; Taheri, Magid
2015-01-01
Assessment of patients' views about the observance of their rights and obtaining feedback from them is an integral component of service quality and ensures healthcare ethics. The aim of this study was to assess patients' awareness of their rights and their satisfaction with observance of their rights, and provide effective strategies to improve the management of patients' rights in hospitals of Markazi Province, Iran in 2012. This analytical study was conducted on 384 patients at 10 hospitals. Patients' awareness of the relevant hospital legislation was assessed by a structured interview, and then patients' satisfaction with observance of their rights was measured by a standardized questionnaire consisting of 10 principles approved by the Iran Ministry of Health of Iran in 2012. In this study, through Delphi technique, effective strategies have been provided to improve the management of patients' rights in the hospitals of Iran. Analysis of variance (ANOVA), t-test, and Z test were applied for data analysis. Overall, 89% of the patients were unaware of the relevant hospital legislation and 28% of them were not satisfied with the observance of their rights (1.4 ± 0.6). A significant difference was observed between observance of patients' rights according to hospitals, language, and place of residence of the patients (P rights according to sex, education, job, and duration of hospital stay (P > 0.05). The Patient Bill of Rights of Iran needs further revision and modification. Moreover, extensive education of patients and healthcare processionals as the most structural strategies to promote professional ethics, reduce ethical conflict, and increase implementation of the law to respect patients' rights should be taken into deeper consideration.
Baker, Sabine; Sanders, Matthew R; Turner, Karen M T; Morawska, Alina
2017-04-01
This randomized controlled trial examined the efficacy of Triple P Online Brief, a low-intensity online positive parenting program for parents of children with early onset disruptive behavior problems. Two hundred parents with 2-9-year-old children displaying early onset disruptive behavior difficulties were randomly assigned to either the intervention condition (n = 100) or a Waitlist Control group (n = 100). At 8-week post-assessment, parents in the intervention group displayed significantly less use of ineffective parenting strategies and significantly more confidence in dealing with a range of behavior concerns. These effects were maintained at 9-month follow-up assessment. A delayed effect was found for child behavior problems, with parents in the intervention group reporting significantly fewer and less frequent child behavior problems at follow-up, but not at post-assessment. All effect sizes were in the small to medium range. There were no significant improvements in observed negative parent and child behavior. No change was seen for parents' adjustment, anger, or conflict over parenting. Consumer satisfaction ratings for the program were high. A brief, low-intensity parenting program delivered via the Internet can bring about significant improvements in parenting and child behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.
Postel, M.G.; Haan, H.A. de; Huurne, E.D. ter; Becker, E.S.; Jong, C.A.J. de
2010-01-01
Background: Online self-help interventions for problem drinkers show promising results, but the effectiveness of online therapy with active involvement of a therapist via the Internet only has not been examined. Objective: The objective of our study was to evaluate an e-therapy program with active t
Postel, M.G.; Haan, H.A. de; Huurne, E.D. ter; Becker, E.S.; Jong, C.A.J. de
2010-01-01
Background: Online self-help interventions for problem drinkers show promising results, but the effectiveness of online therapy with active involvement of a therapist via the Internet only has not been examined. Objective: The objective of our study was to evaluate an e-therapy program with active
Stephanov, M A; Wettig, T
2005-01-01
We review elementary properties of random matrices and discuss widely used mathematical methods for both hermitian and nonhermitian random matrix ensembles. Applications to a wide range of physics problems are summarized. This paper originally appeared as an article in the Wiley Encyclopedia of Electrical and Electronics Engineering.
Does Individual Placement and Support satisfy the users` needs?
Sandra eViering
2015-06-01
Full Text Available This study aims to investigate clients’ satisfaction with Individual Placement and Support (IPS at the University Hospital for Psychiatry Zurich (PUK. Furthermore this study aims to investigate if clients feel the approach of IPS as a useful approach to fulfill their needs. 125 people were recruited from one of the three IPS services of PUK and were asked to complete a structured questionnaire. The following IPS services were available: i randomized controlled trial ZHEPP (www.zhepp.ch, ii randomized controlled trial ZInEP (www.zinep.ch and iii us clinical SE service of PUK (IPS-PUK. The clients mostly indicated that the IPS was generally useful and fitted their needs. Overall satisfaction of the participants with the IPS services of PUK was very high. Furthermore, this study confirms that client satisfaction and symptom severity are associated. In conclusion, participants of the IPS services received the support they were looking for. This means that the approach of IPS fits the needs of different patient groups and can be used without any modifications. The most important limitation is the unequal group sizes. Therefore, the obtained results need to be strengthen by future research.
Wade, Shari L; Taylor, H Gerry; Cassedy, Amy; Zhang, Nanhua; Kirkwood, Michael W; Brown, Tanya M; Stancin, Terry
2015-07-01
Family problem-solving therapy (FPST) has been shown to reduce behavior problems after pediatric traumatic brain injury (TBI). It is unclear whether treatment gains are maintained. We sought to evaluate the maintenance of improvements in behavior problems after a Web-based counselor-assisted FPST (CAPS) intervention compared to an Internet resource comparison (IRC) intervention provided to adolescents within the initial year post-TBI. We hypothesized that family socioeconomic status, child educational status, and baseline levels of symptoms would moderate the efficacy of the treatment over time. Participants included 132 adolescents ages 12-17 years who sustained a complicated mild-to-severe TBI 1-6 months before study enrollment. Primary outcomes were the Child Behavior Checklist Internalizing and Externalizing Totals. Mixed-models analyses, using random intercepts and slopes, were conducted to examine group differences over time. There was a significant group×time×grade interaction (F(1,304)=4.42; p=0.03) for internalizing problems, with high school-age participants in CAPS reporting significantly lower symptoms at 18 months postbaseline than those in the IRC. Post-hoc analyses to elucidate the nature of effects on internalizing problems revealed significant group×time×grade interactions for the anxious/depressed (p=0.03) and somatic complaints subscales (p=0.04). Results also indicated significant improvement over time for CAPS participants who reported elevated externalizing behavior problems at baseline (F(1, 310)=7.17; p=0.008). Findings suggest that CAPS may lead to long-term improvements in behavior problems among older adolescents and those with pretreatment symptoms.
LEE Seung-Ju; SUN Dong; MILLS James K
2006-01-01
The application of a closed-loop specification oriented feedback control design method,which addresses the design of controllers to satisfy multiple simultaneous conflicting closed-loop performance specifications is presented. The proposed approach is well suited to the design of controllers which must meet a set of conflicting performance specifications. Gain tuning is central to the design process, however, the tuning process is greatly simplified over that presented by the problem of tuning a PID controller for example. The proposed control method is applied to an AC induction motor, with an inner-loop flux vector controller applied to design a position control system. Experimental results verify the effectiveness of this method.
Goranko, Valentin
2009-01-01
We study the multiagent epistemic logic CMAELCD with operators for common and distributed knowledge for all coalitions of agents. We introduce Hintikka structures for this logic and prove that satisfiability in such structures is equivalent to satisfiability in standard models. Using this result, we design an incremental tableau based decision procedure for testing satisfiability in CMAELCD.
Brunet, Éric; Derrida, Bernard
2004-07-01
We calculate exactly the velocity and diffusion constant of a microscopic stochastic model of N evolving particles which can be described by a noisy traveling-wave equation with a noise of order N-1/2 . Our model can be viewed as the infinite range limit of a directed polymer in random medium with N sites in the transverse direction. Despite some peculiarities of the traveling-wave equations in the absence of noise, our exact solution allows us to test the validity of a simple cutoff approximation and to show that, in the weak noise limit, the position of the front can be completely described by the effect of the noise on the first particle.
KT an S4 satisfiability in a constraint logic environment
Stevenson, L
2008-12-01
Full Text Available satisfaction problem (CSP) [5, 6]. In this paper, we further investigate the feasibility of the constraint-based ap- proach proposed by Brand et al. [5, 6]. A modal formula is stratified into layers, each of which is solved using the constraint logic.... The solver developed by Brand et al. is, however, limited to the modal logic K. It only deals with formulae that are in conjunctive normal form (CNF), and have not been optimized using any of the standard techniques such as caching. In this paper, we...
Ramadhani, T.; Hertono, G. F.; Handari, B. D.
2017-07-01
The Multiple Traveling Salesman Problem (MTSP) is the extension of the Traveling Salesman Problem (TSP) in which the shortest routes of m salesmen all of which start and finish in a single city (depot) will be determined. If there is more than one depot and salesmen start from and return to the same depot, then the problem is called Fixed Destination Multi-depot Multiple Traveling Salesman Problem (MMTSP). In this paper, MMTSP will be solved using the Ant Colony Optimization (ACO) algorithm. ACO is a metaheuristic optimization algorithm which is derived from the behavior of ants in finding the shortest route(s) from the anthill to a form of nourishment. In solving the MMTSP, the algorithm is observed with respect to different chosen cities as depots and non-randomly three parameters of MMTSP: m, K, L, those represents the number of salesmen, the fewest cities that must be visited by a salesman, and the most number of cities that can be visited by a salesman, respectively. The implementation is observed with four dataset from TSPLIB. The results show that the different chosen cities as depots and the three parameters of MMTSP, in which m is the most important parameter, affect the solution.
Efficient Interpolant Generation in Satisfiability Modulo Linear Integer Arithmetic
Griggio, Alberto; Sebastiani, Roberto
2010-01-01
The problem of computing Craig interpolants in SAT and SMT has recently received a lot of interest, mainly for its applications in formal verification. Efficient algorithms for interpolant generation have been presented for some theories of interest ---including that of equality and uninterpreted functions, linear arithmetic over the rationals, and their combination--- and they are successfully used within model checking tools. For the theory of linear arithmetic over the integers (LA(Z)), however, the problem of finding an interpolant is more challenging, and the task of developing efficient interpolant generators for the full theory LA(Z) is still the objective of ongoing research. In this paper we try to close this gap. We build on previous work and present a novel interpolation algorithm for SMT(LA(Z)), which exploits the full power of current state-of-the-art SMT(LA(Z)) solvers. We demonstrate the potential of our approach with an extensive experimental evaluation of our implementation of the proposed al...
FUZZY SATISFYING INTERACTIVE MULTIOBJECTIVE THERMAL POWER DISPATCH: SWT APPROACH
Lakhwinder SINGH; J.S.DHILLON
2007-01-01
In multiobjective optimization,trade-off analysis plays an important role in determining most preferred solution.This paper presents an explicit interactive trade-off analysis based on the surrogate worth trade-off function to determine the best compromised solution.In the multiobjective framework thermal power dispatch problem is undertaken in which four objectives viz.Cost,Nox emission,Sox emission and Cox emission are minimized simultaneously.The interactive process is implemented using a weighting method by regulating the relative weights of objectives in systematic manner.Hence the weighting method facilitates to simulate the trade-offrelation between the conflicting objectives in non-inferior domain.Exploiting fuzzy decision making theory to access the indifference band,interaction with the decision maker is obtained via surrogate worth trade-off (SWT) functions of the objectives.The surrogate worth trade-off functions are constructed in the functional space and then transformed into the decision space,so the surrogate worth trade-off functions of objectives relate the decision maker's preferences to non-inferior solutions through optimal weight patterns.The optimal solution of thermal power dispatch problem is obtained by considering real and reactive power losses.Decoupled load flow analysis is performed to find the transmission losses.The validity of the proposed method is demonstrated on 11-bus,17-lines IEEE system,comprising of three generators.
Chien, Wai Tong; Thompson, David R; Lubman, Dan I; McCann, Terence V
2016-11-01
Family interventions for first-episode psychosis (FEP) are an integral component of treatment, with positive effects mainly on patients' mental state and relapse rate. However, comparatively little attention has been paid to the effects of family interventions on caregivers' stress coping and well-being, especially in non-Western countries. We aimed to test the effects of a 5-month clinician-supported problem-solving bibliotherapy (CSPSB) for Chinese family caregivers of people with FEP in improving family burden and carers' problem-solving and caregiving experience, and in reducing psychotic symptoms and duration of re-hospitalizations, compared with those only received usual outpatient family support (UOFS). A randomized controlled trial was conducted across 2 early psychosis clinics in Hong Kong, where there might be inadequate usual family support services for FEP patients. A total of 116 caregivers were randomly selected, and after baseline measurement, randomly assigned to the CSPSB or UOFS. They were also assessed at 1-week and 6- and 12-month post-intervention. Intention-to-treat analyses were applied and indicated that the CSPSB group reported significantly greater improvements in family burden and caregiving experience, and reductions in severity of psychotic symptoms and duration of re-hospitalizations, than the UOFS group at 6- and 12-month follow-up. CSPSB produces moderate long-term benefits to caregivers and FEP patients, and is a low-cost adjunct to UOFS. © The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.
Molander, Peter; Hesser, Hugo; Weineland, Sandra; Bergwall, Kajsa; Buck, Sonia; Jäder Malmlöf, Johan; Lantz, Henning; Lunner, Thomas; Andersson, Gerhard
2017-09-12
Psychological distress is common among people with hearing problems, but treatments that specifically target this aspect have been almost non-existent. In this pilot randomized controlled trial, an eight-week long Internet-based treatment, informed by Acceptance and Commitment Therapy, was administered to explore the feasibility and efficacy of such a treatment. Included participants were randomized to either treatment (n = 31) or wait-list control (n = 30) condition. All participants were measured prior to randomization and immediately after treatment ended using standardized self-report instruments measuring hearing-related emotional and social adjustment (Hearing Handicap Inventory for the Elderly - S, HHIE-S), quality of life (Quality of Life Inventory, QOLI), and symptoms of depression and anxiety (Patient health Questionnaire, PHQ-9 and Generalized Anxiety Disorder scale, GAD-7). Linear mixed effects regression analysis using the full intention-to-treat sample demonstrated that the treatment had superior outcomes on the main outcome measure as compared with the control group, Cohen's d = 0.93, 95% CI [0.24, 1.63]. The benefits of treatment over control were also evident in scores of depression, Cohen's d = 0.61, 95% CI [0.04, 1.19], and quality of life, Cohen's d = 0.88, 95% CI [0.14, 1.61]. The results provide preliminary support for Internet-delivered acceptance and commitment therapy as a potentially effective treatment of psychological symptoms associated with hearing problems.
P.V. Krishna Iyer
1957-01-01
Full Text Available The t-test commonly used for testing two samples is based on the assumption that the sample are random and belong to the same normal population. These assumptions may or may not be valid for different types of experimental data. In cases where these assumptions do not hold good, it would be preferable to use tests which are independent of the nature of the distribution of the parent population. A number of such tests, some developed in the Defence Science Laboratory, is given in this paper. The test depend on a sequence of A's and B's obtained by pooling together the two samples {Xm}and {Yn} and arranging them in ascending or descending order and treating the observations belonging to {xm} and {yn} as A's and B's respectively. For this sequence the number of AB's or AB's and BA's are noted for the following cases: (1 Between any two observations of the sequence separated by (k-1 observations or less; (2 Between any two observations in blocks of (k+1 consecutive observations moving from one end to the other end. It has been found that the standardized deviates of these statics serve as more reliable tests than any of other existing tests. Further work is in progress to confirm these findings.
Christensen, Darren R; Dowling, Nicki A; Jackson, Alun C; Thomas, Shane A
2015-12-01
Demographic characteristics associated with gambling participation and problem gambling severity were investigated in a stratified random survey in Tasmania, Australia. Computer-assisted telephone interviews were conducted in March 2011 resulting in a representative sample of 4,303 Tasmanian residents aged 18 years or older. Overall, 64.8% of Tasmanian adults reported participating in some form of gambling in the previous 12 months. The most common forms of gambling were lotteries (46.5%), keno (24.3%), instant scratch tickets (24.3%), and electronic gaming machines (20.5%). Gambling severity rates were estimated at non-gambling (34.8%), non-problem gambling (57.4%), low risk gambling (5.3%), moderate risk (1.8%), and problem gambling (.7%). Compared to Tasmanian gamblers as a whole significantly higher annual participation rates were reported by couples with no children, those in full time paid employment, and people who did not complete secondary school. Compared to Tasmanian gamblers as a whole significantly higher gambling frequencies were reported by males, people aged 65 or older, and people who were on pensions or were unable to work. Compared to Tasmanian gamblers as a whole significantly higher gambling expenditure was reported by males. The highest average expenditure was for horse and greyhound racing ($AUD 1,556), double the next highest gambling activity electronic gaming machines ($AUD 767). Compared to Tasmanian gamblers as a whole problem gamblers were significantly younger, in paid employment, reported lower incomes, and were born in Australia. Although gambling participation rates appear to be falling, problem gambling severity rates remain stable. These changes appear to reflect a maturing gambling market and the need for population specific harm minimisation strategies.
Modelling of the evolutional methods to satisfy the consumer’s needs in new product development
L.K. Hlinenko
2014-09-01
Full Text Available The aim of the article. The aim of the article is development of evolutional models of methods and means of satisfying the consumer needs in a form of corresponding lines of development represented by sets of successive discrete states regularly passed by these methods and means in the process of evolution. Such models are supposed to match demands of the NPD process providing objective appraisal and predicting of the consumer value of innovation taking into account the change of consumer needs of and attitude toward the methods of satisfying them under global market changes and consumer trends that these changes reflect. The results of the analysis. New product correspondence with customer needs is one of the critical terms of their market success. Existing methods of estimation of this correspondence make it possible to estimate only “obvious” needs and demands in the moment or during the period of interaction with the consumer while latent and future needs remain beyond the investigation. Consumers are not static in their needs and behaviour, their demands to level and means of satisfaction of needs change under the influence of volatile environment and as a result of consumer self-development. Collected and proceeded by traditional marketing research technologies data does not provide in-depth and reliable understanding even of present state of consumer needs structure because of difficulties of synchronization and integration of varied consumer inputs and fuzziness of consumer segments; a problem of future needs identification for successful new product development is still left in abeyance. Satisfaction of any need evolves in direction of “idealization” i.e. satisfying in a moment and place of emergence of the need free of charge on the process of satisfying. The idealization trend is realized through: 1 dynamization, integration and specialization of needs; 2 increase of level of satisfaction of every need and number of
Porzig-Drummond, Renata; Stevenson, Richard J; Stevenson, Caroline
2014-07-01
This study investigated the effectiveness of the 1-2-3 Magic parenting program, a brief cognitive-behavioral program, when delivered to large groups of caregivers. The effectiveness of two versions of the programs in reducing child problem behaviors and dysfunctional parenting, and the effect on emotion-related parenting style, were examined. Ninety-two participants with 2-12-year-old children were randomly assigned to one of three groups: DVD (n = 31); Emotion-coaching (EC) (n = 31); or Waitlist-control (n = 30). Both intervention groups reported significantly decreased child problem behaviors, dysfunctional parenting, parental depression and parental stress at post-intervention as compared to the control group. Additionally, the DVD group reported decreased parental anxiety, and the EC group reported a decrease in emotion-dismissing parenting style. Emotion-coaching parenting style remained unchanged for all groups at post-intervention. The results were maintained after three months. After two years, all intervention effects were maintained for the DVD group. For the EC group, effects were maintained on the main outcome variables. The results suggest that both 1-2-3 Magic programs are effective at reducing child problem behavior and dysfunctional parenting when delivered to large groups of caregivers, and that both programs are suitable for a broad delivery approach.
A survey on orthogonal matrix polynomials satisfying second order differential equations
Duran, Antonio J.; Grunbaum, F. Alberto
2005-06-01
The subject of orthogonal polynomials cuts across a large piece of mathematics and its applications. Two notable examples are mathematical physics in the 19th and 20th centuries, as well as the theory of spherical functions for symmetric spaces. It is also clear that many areas of mathematics grew out of the consideration of problems like the moment problem that are intimately associated to the study of (scalar valued) orthogonal polynomials.Matrix orthogonality on the real line has been sporadically studied during the last half century since Krein devoted some papers to the subject in 1949, see (AMS Translations, Series 2, vol. 97, Providence, Rhode Island, 1971, pp. 75-143, Dokl. Akad. Nauk SSSR 69(2) (1949) 125). In the last decade this study has been made more systematic with the consequence that many basic results of scalar orthogonality have been extended to the matrix case. The most recent of these results is the discovery of important examples of orthogonal matrix polynomials: many families of orthogonal matrix polynomials have been found that (as the classical families of Hermite, Laguerre and Jacobi in the scalar case) satisfy second order differential equations with coefficients independent of n. The aim of this paper is to give an overview of the techniques that have led to these examples, a small sample of the examples themselves and a small step in the challenging direction of finding applications of these new examples.
Linton, Steven J; Boersma, Katja; Traczyk, Michal; Shaw, William; Nicholas, Michael
2016-06-01
Purpose There is a clear need for interventions that successfully prevent the development of disability due to back pain. We hypothesized that an intervention aimed at both the worker and the workplace could be effective. Hence, we tested the effects of a new early intervention, based on the misdirected problem solving model, aimed at both workers at risk of long-term impairments and their workplace. Methods Supervisors of volunteers with back pain, no red flags, and a high score on a screen (Örebro Musculoskeletal Screening Questionnaire) were randomized to either an evidence based treatment as usual (TAU) or to a worker and workplace package (WWP). The WWP intervention included communication and problem solving skills for the patient and their immediate supervisor. The key outcome variables of work absence due to pain, health-care utilization, perceived health, and pain intensity were collected before, after and at a 6 month follow up. Results The WWP showed significantly larger improvements relative to the TAU for work absence due to pain, perceived health, and health-care utilization. Both groups improved on pain ratings but there was no significant difference between the groups. The WWP not only had significantly fewer participants utilizing health care and work absence due to pain, but the number of health care visits and days absent were also significantly lower than the TAU. Conclusions The WWP with problem solving and communication skills resulted in fewer days off work, fewer health care visits and better perceived health. This supports the misdirected problem solving model and indicates that screening combined with an active intervention to enhance skills is quite successful and likely cost-effective. Future research should replicate and extend these findings with health-economic analyses.
Mohammad Hassan Sebt
2015-11-01
Full Text Available In this paper, a new genetic algorithm (GA is presented for solving the multi-mode resource-constrained project scheduling problem (MRCPSP with minimization of project makespan as the objective subject to resource and precedence constraints. A random key and the related mode list (ML representation scheme are used as encoding schemes and the multi-mode serial schedule generation scheme (MSSGS is considered as the decoding procedure. In this paper, a simple, efficient fitness function is proposed which has better performance compared to the other fitness functions in the literature. Defining a new mutation operator for ML is the other contribution of the current study. Comparing the results of the proposed GA with other approaches using the well-known benchmark sets in PSPLIB validates the effectiveness of the proposed algorithm to solve the MRCPSP.
Xu, Jiuping; Feng, Cuiying
2014-01-01
This paper presents an extension of the multimode resource-constrained project scheduling problem for a large scale construction project where multiple parallel projects and a fuzzy random environment are considered. By taking into account the most typical goals in project management, a cost/weighted makespan/quality trade-off optimization model is constructed. To deal with the uncertainties, a hybrid crisp approach is used to transform the fuzzy random parameters into fuzzy variables that are subsequently defuzzified using an expected value operator with an optimistic-pessimistic index. Then a combinatorial-priority-based hybrid particle swarm optimization algorithm is developed to solve the proposed model, where the combinatorial particle swarm optimization and priority-based particle swarm optimization are designed to assign modes to activities and to schedule activities, respectively. Finally, the results and analysis of a practical example at a large scale hydropower construction project are presented to demonstrate the practicality and efficiency of the proposed model and optimization method.
Carter Alice S
2011-06-01
Full Text Available Abstract Background The prevalence of social-emotional and behavioral problems is estimated to be 8 to 9% among preschool children. Effective early detection tools are needed to promote the provision of adequate care at an early stage. The Brief Infant-Toddler Social and Emotional Assessment (BITSEA was developed for this purpose. This study evaluates the effectiveness of the BITSEA to enhance social-emotional and behavioral health of preschool children. Methods and Design A cluster randomized controlled trial is set up in youth health care centers in the larger Rotterdam area in the Netherlands, to evaluate the BITSEA. The 31 youth health care centers are randomly allocated to either the control group or the intervention group. The intervention group uses the scores on the BITSEA and cut-off points to evaluate a child's social-emotional and behavioral health and to decide whether or not the child should be referred. The control group provides care as usual, which involves administering a questionnaire that structures the conversation between child health professionals and parents. At a one year follow-up measurement the social-emotional and behavioral health of all children included in the study population will be evaluated. Discussion It is hypothesized that better results will be found, in terms of social-emotional and behavioral health in the intervention group, compared to the control group, due to more adequate early detection, referral and more appropriate and timely care. Trial registration Current Controlled Trials NTR2035
Refining Behavioral Specification for Satisfying Non-functional Requirements of Stakeholders
Kaiya, H; Kaijiri, k
2002-01-01
System specifications should be refined to meet stakeholders' requirements as much as possible, because the first specification does not satisfy all stakeholders in general. This paper presents a procedure to refine behavioral specification to satisfy stakeholders. Non-functional requirements are used for checking stakeholders' satisfaction. With this procedure, stakeholder-dissatisfaction can be reduced and new possibilities to satisfy or dissatisfy other stakeholders can be found, since a m...
2016-01-01
Objective The aim of the present investigation was to compare the effectiveness of Parent-Child Interaction Therapy (PCIT) with treatment as usual (TAU) in young children who were referred to regular child and adolescent mental health clinics for behavior problems. Method Eighty-one Norwegian families with two- to seven-year-old children (52 boys) who had scored ≥ 120 on the Eyberg Child Behavior Inventory (ECBI) were randomly assigned to receive either PCIT or TAU. The families were assessed 6 and 18 months after beginning treatment. Parenting skills were measured using the Dyadic Parent-Child Interaction Coding System (DPICS), and child behavior problems were measured using the ECBI and the Child Behavior Checklist (CBCL). Results Linear growth curve analyses revealed that the behavior problems of children receiving PCIT improved more compared with children receiving TAU according to mother reports (ECBI d = .64, CBCL d = .61, both p Parents also improved with regard to Do and Don’t skills (d = 2.58, d = 1.46, respectively, both p ≤ .001). At the 6-month assessment, which often occurred before treatment was finished, children who had received PCIT had lower father-rated ECBI and mother-rated CBCL-scores (p = .06) compared with those who had received TAU. At the 18-month follow-up, the children who had received PCIT showed fewer behavior problems compared with TAU according to mother (d = .37) and father (d = .56) reports on the ECBI and mother reports on the CBCL regarding externalizing problems (d = .39). Parents receiving PCIT developed more favorable Do Skills (6-month d = 1.81; 18-month d = 1.91) and Don’t Skills (6-month d = 1.46; 18-month d = 1.42) according to observer ratings on the DPICS compared with those receiving TAU. Conclusion Children receiving PCIT in regular clinical practice exhibited a greater reduction in behavior problems compared with children receiving TAU, and their parents' parenting skills improved to a greater degree compared
The Equivalence Forms of Random Kolmogorov Forward (Backward) Equations
HU Di-he; HU Xiao-yu
2005-01-01
The concepts of Markov process in random environment, q-matrix in random environment and q-process in random environment are introduced. Three forms of random Kolmoogrov farward (or backward) equations are introduced and the equivalence of these three forms are also proved. Moreover any conservative q-process in random environment satisfies random Kolmogrov backward equation.
Hutchings, Judy; Martin-Forbes, Pam; Daley, David; Williams, Margiad Elen
2013-10-01
This randomized controlled trial (RCT) evaluated the efficacy of the Incredible Years (IY) Teacher Classroom Management (TCM; Webster-Stratton & Reid, 2002) program to assess whether training teachers in IY-TCM principles improve teacher behavior, whether any observed improvements impact pupil behavior classroom-wide, and whether these effects can be demonstrated with children at risk of developing conduct problems. Six intervention and six control classrooms comprising 12 teachers and 107 children (aged 3 to 7years) were recruited. Children were screened for high or low behavior problems using the cut-off points of the teacher-rated Strengths and Difficulties Questionnaire (Goodman, 1997). The primary outcome measure was independent classroom observations using the Teacher-Pupil Observation Tool (Martin et al., 2010). Multilevel modeling analyses were conducted to examine the effect of the intervention on teacher, classroom, and child behavior. Results showed a significant reduction in classroom off-task behavior (d=0.53), teacher negatives to target children (d=0.36), target child negatives towards the teacher (d=0.42), and target child off-task behavior (d=0.48). These preliminary results demonstrate the potential impact of IY-TCM on both teacher and child behavior. Copyright © 2013 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Heuristic Algorithms for Solving the Slot Planning Problem
Parreno, Francisco; Pacino, Dario; Alvarez-Valdes, Ramon
In the Slot Planning Problem, for each location of the container ship we are given a list of containers to be loaded, and the problem is to assign each container to a feasible position, satisfying the specific packing constraints associated to the ship locations and to the different types...... of containers involved. We have developed a GRASP algorithm in which the constructive randomized phase packs as many containers as possible and the improvement phase tries several moves in order to minimize the number of containers left out. The algorithm has been tested on a set of real-world instances....
Kaipainen, Kirsikka; Lappalainen, Raimo; Hoffrén, Henna; Myllymäki, Tero; Kinnunen, Marja-Liisa; Mattila, Elina; Happonen, Antti P; Rusko, Heikki; Korhonen, Ilkka
2013-01-01
Background Work-related stress is a significant problem for both people and organizations. It may lead to mental illnesses such as anxiety and depression, resulting in increased work absences and disabilities. Scalable interventions to prevent and manage harmful stress can be delivered with the help of technology tools to support self-observations and skills training. Objective The aim of this study was to assess the feasibility of the P4Well intervention in treatment of stress-related psychological problems. P4Well is a novel intervention which combines modern psychotherapy (the cognitive behavioral therapy and the acceptance and commitment therapy) with personal health technologies to deliver the intervention via multiple channels, includinggroup meetings, Internet/Web portal, mobile phone applications, and personal monitoring devices. Methods This pilot study design was a small-scale randomized controlled trial that compared the P4Well intervention with a waiting list control group. In addition to personal health technologies for self-assessment, the intervention consisted of 3 psychologist-assisted group meetings. Self-assessed psychological measures through questionnaires were collected offline pre- and post-intervention, and 6 months after the intervention for the intervention group. Acceptance and usage of technology tools were measured with user experience questionnaires and usage logs. Results A total of 24 subjects were randomized: 11 participants were followed up in the intervention group (1 was lost to follow-up) and 12 participants did not receive any intervention (control group). Depressive and psychological symptoms decreased and self-rated health and working ability increased. All participants reported they had benefited from the intervention. All technology tools had active users and 10/11 participants used at least 1 tool actively. Physiological measurements with personal feedback were considered the most useful intervention component. Conclusions
Sahler, Olle Jane Z; Dolgin, Michael J; Phipps, Sean; Fairclough, Diane L; Askins, Martha A; Katz, Ernest R; Noll, Robert B; Butler, Robert W
2013-04-01
Diagnosis of cancer in a child can be extremely stressful for parents. Bright IDEAS, a problem-solving skills training (PSST) intervention, has been shown to decrease negative affectivity (anxiety, depression, post-traumatic stress symptoms) in mothers of newly diagnosed patients. This study was designed to determine the specificity of PSST by examining its direct and indirect (eg, social support) effects compared with a nondirective support (NDS) intervention. This randomized clinical trial included 309 English- or Spanish-speaking mothers of children diagnosed 2 to 16 weeks before recruitment. Participants completed assessments prerandomization (T1), immediately postintervention (T2), and at 3-month follow-up (T3). Both PSST and NDS consisted of eight weekly 1-hour individual sessions. Outcomes included measures of problem-solving skill and negative affectivity. There were no significant between-group differences at baseline (T1). Except for level of problem-solving skill, which was directly taught in the PSST arm, outcome measures improved equally in both groups immediately postintervention (T2). However, at the 3-month follow-up (T3), mothers in the PSST group continued to show significant improvements in mood, anxiety, and post-traumatic stress; mothers in the NDS group showed no further significant gains. PSST is an effective and specific intervention whose beneficial effects continue to grow after the intervention ends. In contrast, NDS is an effective intervention while it is being administered, but its benefits plateau when active support is removed. Therefore, teaching coping skills at diagnosis has the potential to facilitate family resilience over the entire course of treatment.
van Mechelen Willem
2007-07-01
Full Text Available Abstract Background Mental health problems often lead to prolonged sick leave. In primary care, the usual approach towards these patients was the advice to take rest and not return to work before all complaints had disappeared. When complaints persist, these patients are often referred to psychologists from primary and specialized secondary care. As an alternative, ways have been sought to activate the Dutch occupational physician (OP in primary care. Early 2000, the Dutch Association of Occupational Physicians (NVAB published a guideline concerning the management by OPs of employees with mental health problems. The guideline received positive reactions from employees, employers and Dutch OPs. This manuscript describes the design of a study, which aims to assess the effects of the guideline, compared with usual care. Methods/Design In a randomized controlled trial (RCT, subjects in the intervention group were treated according to the guideline. The control group received usual care, with minimal involvement of the OP and easy access to a psychologist. Subjects were recruited from two Dutch police departments. The primary outcomes of the study are return to work and treatment satisfaction by the employee, employer, and OP. A secondary outcome is cost-effectiveness of the intervention, compared with usual care. Furthermore, prognostic measures are taken into account as potential confounders. A process evaluation will be done by means of performance indicators, based on the guideline. Discussion In this pragmatic trial, effectiveness instead of efficacy is studied. We will evaluate what is possible in real clinical practice, rather than under ideal circumstances. Many requirements for a high quality trial are being met. Results of this study will contribute to treatment options in occupational health practice for employees on sick leave due to mental health problems. Additionally, they may contribute to new and better-suited guidelines and stepped
Schuurmans Josien
2009-10-01
Full Text Available Abstract Background Even though depression and anxiety are highly prevalent in adolescence, youngsters are not inclined to seek help in regular healthcare. Therapy through the Internet, however, has been found to appeal strongly to young people. The main aim of the present study is to examine the efficacy of preventive Internet-based guided self-help problem-solving therapy with adolescents reporting depressive and anxiety symptoms. A secondary objective is to test potential mediating and moderating variables in order to gain insight into how the intervention works and for whom it works best. Methods/design This study is a randomized controlled trial with an intervention condition group and a wait-list control group. The intervention condition group receives Internet-based self-help problem-solving therapy. Support is provided by a professional and delivered through email. Participants in the wait-list control group receive the intervention four months later. The study population consists of adolescents (12-18-year-olds from the general population who report mild to moderate depressive and/or anxiety symptoms and are willing to complete a self-help course. Primary outcomes are symptoms of depression and anxiety. Secondary outcomes are quality of life, social anxiety, and cost-effectiveness. The following variables are examined for their moderating role: demographics, motivation, treatment credibility and expectancy, externalizing behaviour, perceived social support from parents and friends, substance use, the experience of important life events, physical activity, the quality of the therapeutic alliance, and satisfaction. Mediator variables include problem-solving skills, worrying, mastery, and self-esteem. Data are collected at baseline and at 3 weeks, 5 weeks, 4 months, 8 months, and 12 months after baseline. Both intention-to-treat and completer analyses will be conducted. Discussion This study evaluates the efficacy and mechanisms of
Hoek, Willemijn; Schuurmans, Josien; Koot, Hans M; Cuijpers, Pim
2009-10-12
Even though depression and anxiety are highly prevalent in adolescence, youngsters are not inclined to seek help in regular healthcare. Therapy through the Internet, however, has been found to appeal strongly to young people. The main aim of the present study is to examine the efficacy of preventive Internet-based guided self-help problem-solving therapy with adolescents reporting depressive and anxiety symptoms. A secondary objective is to test potential mediating and moderating variables in order to gain insight into how the intervention works and for whom it works best. This study is a randomized controlled trial with an intervention condition group and a wait-list control group. The intervention condition group receives Internet-based self-help problem-solving therapy. Support is provided by a professional and delivered through email. Participants in the wait-list control group receive the intervention four months later. The study population consists of adolescents (12-18-year-olds) from the general population who report mild to moderate depressive and/or anxiety symptoms and are willing to complete a self-help course. Primary outcomes are symptoms of depression and anxiety. Secondary outcomes are quality of life, social anxiety, and cost-effectiveness. The following variables are examined for their moderating role: demographics, motivation, treatment credibility and expectancy, externalizing behaviour, perceived social support from parents and friends, substance use, the experience of important life events, physical activity, the quality of the therapeutic alliance, and satisfaction. Mediator variables include problem-solving skills, worrying, mastery, and self-esteem. Data are collected at baseline and at 3 weeks, 5 weeks, 4 months, 8 months, and 12 months after baseline. Both intention-to-treat and completer analyses will be conducted. This study evaluates the efficacy and mechanisms of Internet-based problem-solving therapy for adolescents. If Internet
Raney Distributions and Random Matrix Theory
Forrester, Peter J.; Liu, Dang-Zheng
2015-03-01
Recent works have shown that the family of probability distributions with moments given by the Fuss-Catalan numbers permit a simple parameterized form for their density. We extend this result to the Raney distribution which by definition has its moments given by a generalization of the Fuss-Catalan numbers. Such computations begin with an algebraic equation satisfied by the Stieltjes transform, which we show can be derived from the linear differential equation satisfied by the characteristic polynomial of random matrix realizations of the Raney distribution. For the Fuss-Catalan distribution, an equilibrium problem characterizing the density is identified. The Stieltjes transform for the limiting spectral density of the singular values squared of the matrix product formed from inverse standard Gaussian matrices, and standard Gaussian matrices, is shown to satisfy a variant of the algebraic equation relating to the Raney distribution. Supported on , we show that it too permits a simple functional form upon the introduction of an appropriate choice of parameterization. As an application, the leading asymptotic form of the density as the endpoints of the support are approached is computed, and is shown to have some universal features.
Mould, R A
2001-01-01
It is claimed elsewhere that the conscious states of humans must have evolved together with their biological states, and that an ongoing interaction between the two must have occurred to insure that they mirror one another in any species. A quantum mechanical mechanism and an evolutionary model for the assumed mind/body interaction are described below. The present paper outlines the related ontological and epistemological assumptions, showing how the claimed connection between conscious states and physical states should be understood.
Bianchi, Constanza
2013-01-01
This paper explores the main satisfiers and dissatisfiers for international students in Australia's higher educational sector. Using a critical incident technique, this study is conducted with international students of higher education in Australia. Four categories of satisfiers and dissatisfiers emerge from the data which are related to…
Branding and Positioning to Satisfy the Customer's Appetite: An Educational Case Study
Ham, Tim
2010-01-01
Rebranding and positioning a school district has become critical to satisfy the "customer's" appetite, enhance public relations, and advance consumer perceptions. A service design model provides a district with the framework to advance its position by identifying attributes and prompts to satisfy customer needs and increase student enrollment. A…
Mehlsen, Mimi; Platz, Merete; Fromholt, Pia
2003-01-01
In a recent American study, the decades from ages 20 to 59 were most frequently chosen to be the most satisfying. However, one third of the elderly evaluated a decade in old age to be the most satisfying (Field, 1996). The present study was undertaken to investigate whether this finding could be replicated in a larger, representative sample of…
Branding and Positioning to Satisfy the Customer's Appetite: An Educational Case Study
Ham, Tim
2010-01-01
Rebranding and positioning a school district has become critical to satisfy the "customer's" appetite, enhance public relations, and advance consumer perceptions. A service design model provides a district with the framework to advance its position by identifying attributes and prompts to satisfy customer needs and increase student…
Branding and Positioning to Satisfy the Customer's Appetite: An Educational Case Study
Ham, Tim
2010-01-01
Rebranding and positioning a school district has become critical to satisfy the "customer's" appetite, enhance public relations, and advance consumer perceptions. A service design model provides a district with the framework to advance its position by identifying attributes and prompts to satisfy customer needs and increase student…
13 CFR 120.111 - What conditions must an Eligible Passive Company satisfy?
2010-01-01
... each Operating Company). Any ownership structure or legal form may qualify as an Eligible Passive... Passive Company satisfy? 120.111 Section 120.111 Business Credit and Assistance SMALL BUSINESS... Companies § 120.111 What conditions must an Eligible Passive Company satisfy? An Eligible Passive...
31 CFR 547.407 - Payments from blocked accounts to satisfy obligations prohibited.
2010-07-01
... satisfy obligations prohibited. 547.407 Section 547.407 Money and Finance: Treasury Regulations Relating... DEMOCRATIC REPUBLIC OF THE CONGO SANCTIONS REGULATIONS Interpretations § 547.407 Payments from blocked accounts to satisfy obligations prohibited. Pursuant to § 547.201, no debits may be made to a blocked...
Improving the AODV Protocol to Satisfy the Required Level of Reliability for Home Area Networks
Hossein Jafari Pozveh
2016-06-01
Full Text Available For decades, the structure of existing power grids has not changed. It is an old structure that depends heavily on fossil fuel as an energy source, and in the future, this is likely to be critical in the field of energy. To solve these problems and to make optimal use of energy resources, a new concept is proposed, called Smart Grid. Smart Grid is an electric power distribution automation system, which can provide a two-way flow of electricity and information between power plants and consumers. The Smart Grid communications infrastructure consists of different network components, such as Home Area Network (HAN, Neighborhood Area Network (NAN and Wide Area Network (WAN. Achieving the required level of reliability in the transmission of information to all sections, including the HAN, is one of the main objectives in the design and implementation of Smart Grid. This study offers a routing protocol by considering the parameters and constraints of HAN, which, by improving AODV routing protocol, achieves the level of required reliability for data transmission in this network. These improvements include: making table-driven AODV routing protocol, extending the routing protocol to compute multiple paths in a route discovery, simplification and providing the effect of HAN parameters. The results of the NS2 simulation indicate that applying this improved routing protocol in the HAN, satisfies the required level of reliability of the network, which is over 98%.
Janus, K; Amelung, V E; Baker, L C; Gaitanides, M; Rundall, T G; Schwartz, F W
2009-04-01
Understanding the factors that affect physicians' job satisfaction is important not only to physicians themselves, but also to patients, health system managers, and policy makers. Physicians represent the crucial resource in health-care delivery. In order to enhance efficiency and quality in health care, it is indispensable to analyse and consider the motivators of physicians. Physician job satisfaction has significant effects on productivity, the quality of care, and the supply of physicians. The purpose of our study was to assess the associations between work-related monetary and non-monetary factors and physicians' work satisfaction as perceived by similar groups of physicians practicing at academic medical centres in Germany and the U.S.A., two countries that, in spite of differing health-care systems, simultaneously experience problems in maintaining their physician workforce. We used descriptive statistics, factor and correlation analyses to evaluate physicians' responses to a self-administered questionnaire. Our study revealed that overall German physicians were less satisfied than U.S. physicians. With respect to particular work-related predictors of job satisfaction we found that similar factors contributed to job satisfaction in both countries. To improve physicians' satisfaction with working conditions, our results call for the implementation of policies that reduce the time burden on physicians to allow more time for interaction with patients and colleagues, increase monetary incentives, and enhance physicians' participation in the development of care management processes and in managerial decisions that affect patient care.
CARR,ROBERT D.; VEMPALA,SANTOSH
2000-01-25
The authors present a new technique for the design of approximation algorithms that can be viewed as a generalization of randomized rounding. They derive new or improved approximation guarantees for a class of generalized congestion problems such as multicast congestion, multiple TSP etc. Their main mathematical tool is a structural decomposition theorem related to the integrality gap of a relaxation.
Bachem, Rahel; Maercker, Andreas
2016-09-01
Adjustment disorders (AjD) are among the most frequent mental disorders yet often remain untreated. The high prevalence, comparatively mild symptom impairment, and transient nature make AjD a promising target for low-threshold self-help interventions. Bibliotherapy represents a potential treatment for AjD problems. This study investigates the effectiveness of a cognitive behavioral self-help manual specifically directed at alleviating AjD symptoms in a homogenous sample of burglary victims. Participants with clinical or subclinical AjD symptoms following experience of burglary were randomized to an intervention group (n = 30) or waiting-list control group (n = 24). The new explicit stress response syndrome model for diagnosing AjD was applied. Participants received no therapist support and assessments took place at baseline, after the one-month intervention, and at three-month follow-up. Based on completer analyses, group by time interactions indicated that the intervention group showed more improvement in AjD symptoms of preoccupation and in post-traumatic stress symptoms. Post-intervention between-group effect sizes ranged from Cohen's d = .17 to .67 and the proportion of participants showing reliable change was consistently higher in the intervention group than in the control group. Engagement with the self-help manual was high: 87% of participants had worked through at least half the manual. This is the first published RCT of a bibliotherapeutic self-help intervention for AjD problems. The findings provide evidence that a low-threshold self-help intervention without therapist contact is a feasible and effective treatment for symptoms of AjD.
Nagata, Keitaro; Shimasaki, Shinji
2016-01-01
Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with light quarks, however, convergence to wrong limits occurs due to the singularity in the drift term caused by small eigenvalues of the Dirac operator including the mass term. We propose that this singular-drift problem should also be overcome by the gauge cooling with different criteria for choosing the complexified gauge transformation. The idea is tested in chiral Random Matrix Theory for finite density QCD, where exact results are reproduced at zero temperature with light quarks. It is shown that the gauge cooling indeed changes drastically the eigenvalue distribution of the Dirac operator measured during the Langevin process. Despite its non-holomorphic nature, this eigenvalue distribution has a universal diverging behavior at the origin in the chiral limit due to a gene...
Seid, Michael; Varni, James W; Gidwani, Pradeep; Gelhard, Leticia Reyes; Slymen, Donald J
2010-11-01
To test the efficacy of problem-solving skill training (PST) in improving health-related quality of life (HRQOL) of children with persistent asthma from predominantly lower socioeconomic status (SES) Spanish-speaking Hispanic families. Randomized controlled trial comparing standard care waitlist (SC) control, home-visiting asthma education/care coordination (CC), and combined intervention (CC + PST) at baseline, after intervention, and 6-month follow-up. The primary outcome was parent proxy-report child HRQOL (PedsQL). Participants (n = 252) were 83.3% Hispanic and 56.3% monolingual Spanish speakers, and 72.6% of mothers had not graduated high school. We found a significant (P = 0.05) intervention effect for parent proxy-reported child generic (but not asthma-specific) HRQOL, with CC + PST superior to SC [83.8 vs 79.8; adjusted mean difference of 4.05 points (95% confidence interval 0.63-7.4], but no difference between the CC and SC groups. In this sample of vulnerable families of children with persistent asthma, a CC + PST intervention was efficacious in improving children's generic HRQOL.
Greenley, Rachel N; Gumidyala, Amitha P; Nguyen, Eve; Plevinsky, Jill M; Poulopoulos, Natasha; Thomason, Molly M; Walter, Jennifer G; Wojtowicz, Andrea A; Blank, Ellen; Gokhale, Ranjana; Kirschner, Barbara S; Miranda, Adrian; Noe, Joshua D; Stephens, Michael C; Werlin, Steven; Kahn, Stacy A
2015-11-01
Medication nonadherence is associated with higher disease activity, greater health care utilization, and lower health-related quality of life in pediatric inflammatory bowel diseases (IBD). Problem solving skills training (PSST) is a useful tool to improve adherence in patients with chronic diseases but has not been fully investigated in IBD. This study assessed feasibility, acceptability, and preliminary efficacy of PSST in pediatric IBD. Recruitment occurred during outpatient clinic appointments. After completion of baseline questionnaires, families were randomized to a treatment group or wait-list comparison group. The treatment group received either 2 or 4 PSST sessions. Youth health-related quality of life was assessed at 3 time points, and electronic monitoring of oral medication adherence occurred for the study duration. Seventy-six youth (ages 11-18 years) on an oral IBD maintenance medication participated. High retention (86%) and treatment fidelity rates (95%) supported feasibility. High satisfaction ratings (mean values ≥4.2 on 1-5 scale) supported intervention acceptability. Modest increases in adherence occurred after 2 PSST sessions among those with imperfect baseline adherence (d = 0.41, P 0.05). Phone-delivered PSST was feasible and acceptable. Efficacy estimates were similar to those of lengthier interventions conducted in other chronic illness populations. Older adolescents benefited more from the intervention than their younger counterparts.
Nagata, Keitaro; Nishimura, Jun; Shimasaki, Shinji
2016-07-01
Recently, the complex Langevin method has been applied successfully to finite density QCD either in the deconfinement phase or in the heavy dense limit with the aid of a new technique called the gauge cooling. In the confinement phase with light quarks, however, convergence to wrong limits occurs due to the singularity in the drift term caused by small eigenvalues of the Dirac operator including the mass term. We propose that this singular-drift problem should also be overcome by the gauge cooling with different criteria for choosing the complexified gauge transformation. The idea is tested in chiral Random Matrix Theory for finite density QCD, where exact results are reproduced at zero temperature with light quarks. It is shown that the gauge cooling indeed changes drastically the eigenvalue distribution of the Dirac operator measured during the Langevin process. Despite its non-holomorphic nature, this eigenvalue distribution has a universal diverging behavior at the origin in the chiral limit due to a generalized Banks-Casher relation as we confirm explicitly.
Multiple scattering of arbitrarily incident Bessel beams by random discrete particles.
Cui, Zhiwei; Han, Yiping; Ai, Xia
2013-11-01
In this paper, we introduce an efficient numerical method to characterize the multiple scattering by random discrete particles illuminated by Bessel beams with arbitrary incidence. Specifically, the vector expressions of Bessel beams that perfectly satisfy Maxwell's equations in combination with rotation Euler angles are used to represent the arbitrarily incident Bessel beams. A hybrid vector finite element-boundary integral-characteristic-basis function method is utilized to formulate the scattering problems involving multiple discrete particles with a random distribution. Due to the flexibility of the finite element method, the adopted method can conveniently deal with the problems of multiple scattering by randomly distributed homogeneous particles, inhomogeneous particles, and anisotropic particles. Some numerical results are included to illustrate the validity and capability of the proposed method and to show the scattering behaviors of random discrete particles when they are illuminated by Bessel beams.
Mehmet Akalın
2015-06-01
Full Text Available Autism is a term of which we have been aware recently in our country through visual and printed media and which we have seen examples around us. Together with opening Dependent and Independent Education Centres for Children with Autism, children with autism have found the opportunity to receive education in line with their needs. With individual education programs developed by the teacher suitable for the development of the child with autism, they can acquire skills in various development areas. Dressing skill, which is one of the main skills necessary for every individual, is a mandatory skill that children with autism need to acquire to satisfy their own needs. In the first three parts of the study a conceptual frame was given and the definition, history, types, characteristics, and behaviour problems of children with autism were presented, and clothing comfort and other concepts were explained. In the fourth part, method, material, research approach, sample and population, numerals, limitations, data collection technique and data analysis technique were explained and the results were presented in tables. The study was carried out to reveal dressing problems children with autism encounter and to determine to what extent the clothes made by ready-made clothing sector satisfy the needs of children with autism and it was found that children with autism have difficulties in using ready-made clothes.
A form of multidimensional averiging functions satisfying the property of associativity
V. Arnaut
1994-11-01
Full Text Available In this paper multidimensional averiging functions are studied in assumption that they are continuous, monotonic and satisfy the property of associativity. It is proved that such functions are very "closed" to functions MAX( and MIN(.
Theocharis Theofanidis
2016-01-01
Full Text Available Real hypersurfaces satisfying the condition ϕl=lϕ(l=R(·,ξξ have been studied by many authors under at least one more condition, since the class of these hypersurfaces is quite tough to be classified. The aim of the present paper is the classification of real hypersurfaces in complex projective plane CP2 satisfying a generalization of ϕl=lϕ under an additional restriction on a specific function.
Asymptotics of Random Contractions
Hashorva, Enkelejd; Tang, Qihe
2010-01-01
In this paper we discuss the asymptotic behaviour of random contractions $X=RS$, where $R$, with distribution function $F$, is a positive random variable independent of $S\\in (0,1)$. Random contractions appear naturally in insurance and finance. Our principal contribution is the derivation of the tail asymptotics of $X$ assuming that $F$ is in the max-domain of attraction of an extreme value distribution and the distribution function of $S$ satisfies a regular variation property. We apply our result to derive the asymptotics of the probability of ruin for a particular discrete-time risk model. Further we quantify in our asymptotic setting the effect of the random scaling on the Conditional Tail Expectations, risk aggregation, and derive the joint asymptotic distribution of linear combinations of random contractions.
Fredriksson, Albin, E-mail: albin.fredriksson@raysearchlabs.com; Hårdemark, Björn [RaySearch Laboratories, Sveavägen 44, Stockholm SE-111 34 (Sweden); Forsgren, Anders [Optimization and Systems Theory, Department of Mathematics, KTH Royal Institute of Technology, Stockholm SE-100 44 (Sweden)
2015-07-15
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.
OJO Stephen Okunlola
2013-07-01
Full Text Available The need to develop a decision support system to determine the most appropriate procurement route for a building project led to the development of various theoretical models. One of the foremost techniques was the multi-attribute utility approach (MAUA. In this technique, the arithmetic mean (averaging method was used to fix the utility factors relating the procurement routes to each criterion. In this paper, the averaging method was subjected to further analysis using the outranking-satisfying technique to determine the correctness of the results derived from the averaging method used to fix the utility factors in the use of MAUA. The results showed that there is a significant difference between the rank-order of procurement methods against selection criteria by averaging and outranking-satisfying techniques. The use of outranking-satisfying analysis revealed that, the use of arithmetic mean to determine the utility factors can lead to inappropriate association of procurement routes with differing utility coefficients.
On the set of zero coefficients of a function satisfying a linear differential equation
Bell, Jason P; Yeats, Karen
2011-01-01
Let $K$ be a field of characteristic zero and suppose that $f:\\mathbb{N}\\to K$ satisfies a recurrence of the form $$f(n)\\ =\\ \\sum_{i=1}^d P_i(n) f(n-i),$$ for $n$ sufficiently large, where $P_1(z),...,P_d(z)$ are polynomials in $K[z]$. Given that $P_d(z)$ is a nonzero constant polynomial, we show that the set of $n\\in \\mathbb{N}$ for which $f(n)=0$ is a union of finitely many arithmetic progressions and a finite set. This generalizes the Skolem-Mahler-Lech theorem, which assumes that $f(n)$ satisfies a linear recurrence. We discuss examples and connections to the set of zero coefficients of a power series satisfying a homogeneous linear differential equation with rational function coefficients.
Australian primary health care nurses most and least satisfying aspects of work.
Halcomb, Elizabeth; Ashley, Christine
2017-02-01
To identify the aspects of working in Australian primary health care that nurses rate as the most and least satisfying. The nursing workforce in Australian primary health care has grown exponentially to meet the growing demand for health care. To maintain and further growth requires the recruitment and retention of nurses to this setting. Understanding the factors that nurses' rate as the most and least satisfying about their job will inform strategies to enhance nurse retention. A cross-sectional online survey. Nurses employed in primary health care settings across Australia were recruited (n = 1166) to participate in a survey which combined items related to the respondent, their job, type of work, clinical activities, job satisfaction and future intention, with two open-ended items about the most and least satisfying aspects of their work. Patient interactions, respect, teamwork, collegiality and autonomy were identified as the most satisfying professional aspects of their role. Personal considerations such as family friendly work arrangements and a satisfactory work-life balance were also important, overriding negative components of the role. The least satisfying aspects were poor financial support and remuneration, lack of a career path, physical work environment and time constraints. National restructuring of the primary health care environment was seen as a barrier to role stability and ability to work to a full scope of practice. This study has identified a range of positive and negative professional and personal aspects of the primary health care nursing role, which may impact on staff recruitment and retention. Findings from the study should be considered by employers seeking to retain and maximise the skills of their primary health care workforce. Understanding the factors that nurses perceive as being the most and least satisfying aspects of the work is can open up dialogue about how to improve the working experience of nurses in primary health care.
Towards a Framework for Generating Tests to Satisfy Complex Code Coverage in Java Pathfinder
Staats, Matt
2009-01-01
We present work on a prototype tool based on the JavaPathfinder (JPF) model checker for automatically generating tests satisfying the MC/DC code coverage criterion. Using the Eclipse IDE, developers and testers can quickly instrument Java source code with JPF annotations covering all MC/DC coverage obligations, and JPF can then be used to automatically generate tests that satisfy these obligations. The prototype extension to JPF enables various tasks useful in automatic test generation to be performed, such as test suite reduction and execution of generated tests.
Liu, Hailiang; Wang, Zhongming
2017-01-01
We design an arbitrary-order free energy satisfying discontinuous Galerkin (DG) method for solving time-dependent Poisson-Nernst-Planck systems. Both the semi-discrete and fully discrete DG methods are shown to satisfy the corresponding discrete free energy dissipation law for positive numerical solutions. Positivity of numerical solutions is enforced by an accuracy-preserving limiter in reference to positive cell averages. Numerical examples are presented to demonstrate the high resolution of the numerical algorithm and to illustrate the proven properties of mass conservation, free energy dissipation, as well as the preservation of steady states.
The Vehicle Rescheduling Problem
R. Spliet (Remy); A.F. Gabor (Adriana); R. Dekker (Rommert)
2009-01-01
textabstractThe capacitated vehicle routing problem is to find a routing schedule describing the order in which geographically dispersed customers are visited to satisfy demand by supplying goods stored at the depot, such that the traveling costs are minimized. In many practical applications, a long
Lehmann, Monty R.; Nial, Jack; Whitaker, Mike
1992-11-01
The widely differing methods of producing and applying a 300 kV electrostatic stimulus to components during testing to satisfy MIL-STD-331B Appendix F has resulted in uncertainty about the validity of some test results data. Problems encountered in test methodology are examined and possible solutions are proposed. The resulting integrated systematic approach is presented; specific equipment is described, and sample waveforms are shown. Test procedures are presented in a standardized format.
Common Fixed Point Theorems for Weakly Compatible Maps Satisfying a General Contractive Condition
Cristina Di Bari
2008-01-01
Full Text Available We introduce a new generalized contractive condition for four mappings in the framework of metric space. We give some common fixed point results for these mappings and we deduce a fixed point result for weakly compatible mappings satisfying a contractive condition of integral type.
17 CFR 230.482 - Advertising by an investment company as satisfying requirements of section 10.
2010-04-01
... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Advertising by an investment... Investment Companies; Business Development Companies § 230.482 Advertising by an investment company as satisfying requirements of section 10. (a) Scope of rule. This section applies to an advertisement or other...
Tableau tool for testing satisfiability in LTL: Implementation and experimental analysis
Goranko, Valentin; Kyrilov, Angelo; Shkatov, Dmitry
2010-01-01
We report on the implementation and experimental analysis of an incremental multi-pass tableau-based procedure `a la Wolper for testing satisfiability in the linear time temporal logic LTL, based on a breadthfirst search strategy. We describe the implementation and discuss the performance of the ...
Employees facing high job demands: How to keep them fit, satisfied, and intrinsically motivated?
Van Yperen, N.W.; Nagao, DH
2002-01-01
The purpose of the present research was to determine why some employees faced with high job demands feel fatigued, dissatisfied, and unmotivated, whereas others feel fatigued but satisfied and intrinsically motivated. It is argued and demonstrated that two job conditions, namely job control and job
76 FR 71255 - Application of Section 108(e)(8) to Indebtedness Satisfied by a Partnership Interest
2011-11-17
... person related to the partnership) as part of a tax-avoidance plan. Thus, under the final regulations... liquidation value of the debt- for-equity interest for purposes of determining the tax consequences of the... avoidance of COD income by the partnership (anti-abuse provision). If these requirements are not satisfied...
Employees facing high job demands: How to keep them fit, satisfied, and intrinsically motivated?
Van Yperen, N.W.; Nagao, DH
2002-01-01
The purpose of the present research was to determine why some employees faced with high job demands feel fatigued, dissatisfied, and unmotivated, whereas others feel fatigued but satisfied and intrinsically motivated. It is argued and demonstrated that two job conditions, namely job control and job
Can Low-income Americans Afford to Satisfy MyPyramid Fruit and Vegetable Guidelines?
Stewart, Hayden; Hyman, Jeffrey; Frazao, Elizabeth; Buzby, Jean C.; Carlson, Andrea
2011-01-01
Objective: To estimate the costs of satisfying MyPyramid fruit and vegetable guidelines, with a focus on whether low-income households can bear these costs. Design: Descriptive analysis of the 2008 National Consumer Panel with information on the food purchases of 64,440 households across the contiguous United States was used to analyze the cost of…
De Raedt, Hans; De Raedt, Koen; Michielsen, Kristel; Keimpema, Koenraad; Miyashita, Seiji
2007-01-01
Inspired by Einstein-Podolsky-Rosen-Bohtn experiments with photons, we construct an event-based simulation model in which every essential element in the ideal experiment has a counterpart. The model satisfies Einstein's criterion of local causality and does not rely on concepts of quantum and probab
Bounds on the Weight Hierarchies of a Kind of Linear Codes Satisfying Non-Chain Condition
LIUZihui; CHENWende
2005-01-01
The upper bound of weight hierarchies of codes with a divided-chain of arbitrary continuous break points are studied and the codes satisfying the upperbound are constructed by finite projective geometry, in particular, the geometrical construction is tight for the upper-bound weight hierarchies.
Tapiero, Charles S.; Vallois, Pierre
2016-11-01
The premise of this paper is that a fractional probability distribution is based on fractional operators and the fractional (Hurst) index used that alters the classical setting of random variables. For example, a random variable defined by its density function might not have a fractional density function defined in its conventional sense. Practically, it implies that a distribution's granularity defined by a fractional kernel may have properties that differ due to the fractional index used and the fractional calculus applied to define it. The purpose of this paper is to consider an application of fractional calculus to define the fractional density function of a random variable. In addition, we provide and prove a number of results, defining the functional forms of these distributions as well as their existence. In particular, we define fractional probability distributions for increasing and decreasing functions that are right continuous. Examples are used to motivate the usefulness of a statistical approach to fractional calculus and its application to economic and financial problems. In conclusion, this paper is a preliminary attempt to construct statistical fractional models. Due to the breadth and the extent of such problems, this paper may be considered as an initial attempt to do so.
肖继先; 寇春蕾
2015-01-01
文中从不确定理论出发，将随机模糊约束规划理论引入对随机模糊多目标指派问题的研究。构建了多目标指派问题的随机模糊规划机会约束模型，并设计了将随机模糊模拟、神经网络和遗传算法结合在一起的混合智能算法对模型进行求解。%This paper based on the uncertainty theory,put the theory of random fuzzy constraint programming introduce into the study of random fuzzy multi-objective assignment problem.Build random fuzzy planning opportunities constraint model of the Multi -objective Assignment problem.And design a hybrid intelligent algorithm, which combined the random fuzzy simulation,neural network and genetic algorithm,to solve the model.
Kleefman, Marijke; Jansen, Danielle E. M. C.; Stewart, Roy E.; Reijneveld, Sijmen A.
2014-01-01
Background: Children with borderline to mild intellectual disability (BMID) have been shown to be at increased risk for psychosocial problems. The presence of these psychosocial problems leads to parenting stress. Stepping Stones Triple P (SSTP) is a parenting support program to support parents with
Sahler, Olle Jane Z.; Fairclough, Diane L.; Phipps, Sean; Mulhern, Raymond K.; Dolgin, Michael J.; Noll, Robert B.; Katz, Ernest R.; Varni, James W.; Copeland, Donna R.
2005-01-01
Mothers of children with cancer experience significant distress associated with their children's diagnosis and treatment. The efficacy of problem-solving skills training (PSST), a cognitive-behavioral intervention based on problem-solving therapy, was assessed among 430 English- and Spanish-speaking mothers of recently diagnosed patients.…
Kleefman, Marijke; Jansen, Danielle E. M. C.; Stewart, Roy E.; Reijneveld, Sijmen A.
2014-01-01
Background: Children with borderline to mild intellectual disability (BMID) have been shown to be at increased risk for psychosocial problems. The presence of these psychosocial problems leads to parenting stress. Stepping Stones Triple P (SSTP) is a parenting support program to support parents with
Mai A Elobeid
Full Text Available BACKGROUND: Dropouts and missing data are nearly-ubiquitous in obesity randomized controlled trails, threatening validity and generalizability of conclusions. Herein, we meta-analytically evaluate the extent of missing data, the frequency with which various analytic methods are employed to accommodate dropouts, and the performance of multiple statistical methods. METHODOLOGY/PRINCIPAL FINDINGS: We searched PubMed and Cochrane databases (2000-2006 for articles published in English and manually searched bibliographic references. Articles of pharmaceutical randomized controlled trials with weight loss or weight gain prevention as major endpoints were included. Two authors independently reviewed each publication for inclusion. 121 articles met the inclusion criteria. Two authors independently extracted treatment, sample size, drop-out rates, study duration, and statistical method used to handle missing data from all articles and resolved disagreements by consensus. In the meta-analysis, drop-out rates were substantial with the survival (non-dropout rates being approximated by an exponential decay curve (e(-lambdat where lambda was estimated to be .0088 (95% bootstrap confidence interval: .0076 to .0100 and t represents time in weeks. The estimated drop-out rate at 1 year was 37%. Most studies used last observation carried forward as the primary analytic method to handle missing data. We also obtained 12 raw obesity randomized controlled trial datasets for empirical analyses. Analyses of raw randomized controlled trial data suggested that both mixed models and multiple imputation performed well, but that multiple imputation may be more robust when missing data are extensive. CONCLUSION/SIGNIFICANCE: Our analysis offers an equation for predictions of dropout rates useful for future study planning. Our raw data analyses suggests that multiple imputation is better than other methods for handling missing data in obesity randomized controlled trials
Are public officials really less satisfied than private sector workers?A comparative study in Brazil
Renata Borges
2013-12-01
Full Text Available This research aims to compare the public and private sectors with regard to satisfaction at work. We conducted a survey with 670 professionals from both sectors in Brazil. The results of variance analysis confirm previous researches indicating that public officials are less satisfied with their work than private sector workers. However, this result does not repeat when we evaluate the satisfaction dimensions. For instance, public officials reported being more satisfied than private sector workers with regard to social environment and work stability. Unexpectedly, the results suggest that there is no difference between these sectors when we analyze the satisfaction with supervision. Therefore, this article is relevant for Brazilian managers, by offering an empirical research on the distinction between public and private. The article also discusses the theoretical implications, since Brazilian findings do not completely support the international literature.
A Quasi-Interpolation Satisfying Quadratic Polynomial Reproduction with Radial Basis Functions
Li Zha; Renzhong Feng
2007-01-01
In this paper, a new quasi-interpolation with radial basis functions which satisfies quadratic polynomial reproduction is constructed on the infinite set of equally spaced data. A new basis function is constructed by making convolution integral with a constructed spline and a given radial basis function. In particular, for twicely differentiable function the proposed method provides better approximation and also takes care of derivatives approximation.
Rose, Jayln; Glass, Nel
2006-10-01
The article reports on selected findings of a research study concerning emotional wellbeing and professional nursing practice (Rose 2002). It highlights the relationship between community mental health nurses' and emotional wellbeing, and their capacity to provide satisfying professional nursing practice (Rose 2002). The notion of emotional wellbeing, factors that impacted upon the participants' emotional wellbeing, and the relationship of emotional wellbeing to professional practice were revealed in the study. These findings were based on a qualitative critical feminist research inquiry and specifically, interviews with five women community mental health nurses in Australia. Whilst complex, emotional wellbeing was found to be both implicitly and explicitly linked to the participants intertwined personal and professional experiences. Four key components were identified: the nebulous notion; the stress relationship; the mind, body, spirit connection; and, inner sense of balance. In terms of emotional wellbeing and professional practice, three themes were revealed. These were: being able to speak out (or not); being autonomous (or not) and being satisfied (or not). The authors argue that the emotional wellbeing of nurses working in community mental health settings is critical to satisfying professional practice. Furthermore nursing work involves emotional work which impacts on one's emotional wellbeing and emotional wellbeing is integrally linked to professional practice. It is recommended that health organisations must be pro-active in addressing the emotional needs of nurses to ensure the delivery of health care that is aligned to professional practice. This approach will ensure nurses will feel more recognised and validated in terms of their nursing practice.
Tracial gauge norms on finite von Neumann algebras satisfying the weak Dixmier property
Fang, Junsheng; Nordgren, Eric; Shen, Junhao
2007-01-01
In this paper we set up a representation theorem for tracial gauge norms on finite von Neumann algebras satisfying the weak Dixmier property in terms of Ky Fan norms. Examples of tracial gauge norms on finite von Neumann algebras satisfying the weak Dixmier property include unitarily invariant norms on finite factors (type ${\\rm II}\\sb 1$ factors and $M_n(\\cc)$) and symmetric gauge norms on $L^\\infty[0,1]$ and $\\cc^n$. As the first application, we obtain that the class of unitarily invariant norms on a type ${\\rm II}\\sb 1$ factor coincides with the class of symmetric gauge norms on $L^\\infty[0,1]$ and von Neumann's classical result \\cite{vN} on unitarily invariant norms on $M_n(\\cc)$. As the second application, Ky Fan's dominance theorem \\cite{Fan} is obtained for finite von Neumann algebras satisfying the weak Dixmier property. As the third application, some classical results in non-commutative $L^p$-theory (e.g., non-commutative H$\\ddot{\\text{o}}$lder's inequality, duality and reflexivity of non-commutative...
Nonlinear Maps Satisfying Derivability on the Parabolic Subalgebras of the Full Matrix Algebras
Zheng Xin CHEN; Yu E ZHAO
2011-01-01
Let F be a field of characteristic O,Mn(F) the full matrix algebra over F,t the subalgebra of Mn(F) consisting of all upper triangular matrices.Any subalgebra of Mn(F) containing t is called a parabolic subalgebra of Mn(F).Let P be a parabolic subalgebra of Mn(F).A map φ on P is said to satisfy derivability if φ(x·y) =φ(x).y+x·φ(y) for all x,y ∈ P,where φ is not necessarily linear.Note that a map satisfying derivability on P is not necessarily a derivation on P.In this paper,we prove that a map φ on P satisfies derivability if and only if φ is a sum of an inner derivation and an additive quasi-derivation on P.In particular,any derivation of parabolic subalgebras of Mn (F) is an inner derivation.
Tholen Stefan
2011-01-01
Full Text Available Abstract Background Several computational methods exist to suggest rational genetic interventions that improve the productivity of industrial strains. Nonetheless, these methods are less effective to predict possible genetic responses of the strain after the intervention. This problem requires a better understanding of potential alternative metabolic and regulatory pathways able to counteract the targeted intervention. Results Here we present SPABBATS, an algorithm based on Boolean satisfiability (SAT that computes alternative metabolic pathways between input and output species in a reconstructed network. The pathways can be constructed iteratively in order of increasing complexity. SPABBATS allows the accumulation of intermediates in the pathways, which permits discovering pathways missed by most traditional pathway analysis methods. In addition, we provide a proof of concept experiment for the validity of the algorithm. We deleted the genes for the glutamate dehydrogenases of the Gram-positive bacterium Bacillus subtilis and isolated suppressor mutant strains able to grow on glutamate as single carbon source. Our SAT approach proposed candidate alternative pathways which were decisive to pinpoint the exact mutation of the suppressor strain. Conclusions SPABBATS is the first application of SAT techniques to metabolic problems. It is particularly useful for the characterization of metabolic suppressor mutants and can be used in a synthetic biology setting to design new pathways with specific input-output requirements.
Judd, Charles M; Westfall, Jacob; Kenny, David A
2012-07-01
Throughout social and cognitive psychology, participants are routinely asked to respond in some way to experimental stimuli that are thought to represent categories of theoretical interest. For instance, in measures of implicit attitudes, participants are primed with pictures of specific African American and White stimulus persons sampled in some way from possible stimuli that might have been used. Yet seldom is the sampling of stimuli taken into account in the analysis of the resulting data, in spite of numerous warnings about the perils of ignoring stimulus variation (Clark, 1973; Kenny, 1985; Wells & Windschitl, 1999). Part of this failure to attend to stimulus variation is due to the demands imposed by traditional analysis of variance procedures for the analysis of data when both participants and stimuli are treated as random factors. In this article, we present a comprehensive solution using mixed models for the analysis of data with crossed random factors (e.g., participants and stimuli). We show the substantial biases inherent in analyses that ignore one or the other of the random factors, and we illustrate the substantial advantages of the mixed models approach with both hypothetical and actual, well-known data sets in social psychology (Bem, 2011; Blair, Chapleau, & Judd, 2005; Correll, Park, Judd, & Wittenbrink, 2002).
Staal, Ingrid I E; van Stel, Henk F.; Hermanns, Jo M A; Schrijvers, Augustinus J P
2015-01-01
Objective: The early detection of parenting and developmental problems by preventive child health care (CHC) services in the Netherlands takes place almost exclusively at the well-baby clinic. This study assesses whether, compared to a visit to the well-baby clinic, a home visit improves early detec
W. Eijzenga; N.K. Aaronson; I. Kluijt; G.N. Sidharta; D.E.E. Hahn; M.G.E.M. Ausems; E.M.A. Bleiker
2014-01-01
Background: Individuals with a personal or family history of cancer, can opt for genetic counseling and DNA-testing. Approximately 25% of these individuals experience clinically relevant levels of psychosocial distress, depression and/or anxiety after counseling. These problems are frequently left u
Bos, Elisabeth H.; van Wel, E. Bas; Appelo, Martin T.; Verbraak, Marc J. P. M.
2010-01-01
Systems Training for Emotional Predictability and Problem Solving (STEPPS) is a group treatment for persons with borderline personality disorder (BPD) that is relatively easy to implement. We investigated the efficacy of a Dutch version of this treatment (VERS). Seventy-nine DSM-IV BPD patients were
Dekker Jacqueline M
2010-03-01
Full Text Available Abstract Background Drug related problems (DRPs are common among elderly patients who are discharged from the hospital and are using several drugs for their chronic diseases. Examples of drug related problems are contra-indications, interactions, adverse drug reactions and inefficacy of treatment. Causes of these problems include prescription errors and non-compliance with treatment. The aim of this study is to examine the effect of medication review and cognitive behaviour therapy of discharged patients by community pharmacists to minimize the occurrence of drug related problems. Methods/Design A randomized controlled trial will be performed. Community pharmacists will be randomized into a control group and an intervention group. 342 Patients, aged over 60 years, discharged from general and academic hospitals, using five or more prescription drugs for their chronic disease will be asked by their pharmacy to participate in the study. Patients randomized to the control group will receive usual care according to the Dutch Pharmacy Standard. The medication of patients randomised to the intervention group will be reviewed by the community pharmacist with use of the national guidelines for the treatment of diseases, when patients are discharged from the hospital. The Pharmaceutical Care network Europe Registration form will be used to record drug related problems. Trained pharmacy technicians will counsel patients at home at baseline and at 1,3,6,9 and 12 months, using Cognitive Behaviour Treatment according to the Theory of Planned Behaviour. The patient's attitude towards medication and patient's adherence will be subject of the cognitive behaviour treatment. The counselling methods that will be used are motivational interviewing and problem solving treatment. Patients adherence towards drug use will be determined with use of the Medication Adherence Report Scale Questionnaire. There will be a follow-up of 12 months. The two primary outcome
Minami, Kazuhiko
2016-02-01
It is shown that a solvable Hamiltonian can be obtained from a series of operators satisfying specific commutation relations. A transformation that diagonalize the Hamiltonian is obtained simultaneously. The two-dimensional Ising model with periodic interactions, the one-dimensional XY model with period 2, the transverse Ising chain, the one-dimensional Kitaev model and the cluster model, and other composite quantum spin chains are diagonalized following this procedure. The Jordan-Wigner transformation, the transformation from the Pauli spin operators to the Majorana fermion used by Shankar and Murthy, and the transformation introduced by Nambu, are special cases of this treatment.
Baudoin, Fabrice
2012-01-01
By adapting some ideas of M. Ledoux \\cite{ledoux2}, \\cite{ledoux-stflour} and \\cite{Led} to a sub-Riemannian framework we study Sobolev, Poincar\\'e and isoperimetric inequalities associated to subelliptic diffusion operators that satisfy the generalized curvature dimension inequality that was introduced by F. Baudoin and N. Garofalo in \\cite{Bau2}. Our results apply in particular on all CR Sasakian manifolds whose horizontal Webster-Tanaka-Ricci curvature is non negative, all Carnot groups with step two, and wide subclasses of principal bundles over Riemannian manifolds whose Ricci curvature is non negative.
An On-the-fly Tableau-based Decision Procedure for PDL-Satisfiability
Abate, Pietro; Widmann, Florian
2007-01-01
We present a tableau-based algorithm for deciding satisfiability for propositional dynamic logic (PDL) which builds a finite rooted tree with ancestor loops and passes extra information from children to parents to separate good loops from bad loops during backtracking. It is easy to implement, with potential for parallelisation, because it constructs a pseudo-model ``on the fly'' by exploring each tableau branch independently. But its worst-case behaviour is 2EXPTIME rather than EXPTIME. A prototype implementation in the TWB (http://twb.rsise.anu.edu.au) is available.
Randomly weighted sums of subexponential random variables with application to ruin theory
Tang, Q.; Tsitsiashvili, G.
2003-01-01
Let {X k , 1 k n} be n independent and real-valued random variables with common subexponential distribution function, and let {k, 1 k n} be other n random variables independent of {X k , 1 k n} and satisfying a k b for some 0 < a b < for all 1 k n. This paper proves that the asymptotic relations P (
Randomly weighted sums of subexponential random variables with application to ruin theory
Tang, Q.; Tsitsiashvili, G.
2003-01-01
Let {X k , 1 k n} be n independent and real-valued random variables with common subexponential distribution function, and let {k, 1 k n} be other n random variables independent of {X k , 1 k n} and satisfying a k b for some 0 < a b < for all 1 k n. This paper proves that the asymptotic relations P (
Foxcroft David R
2008-04-01
Full Text Available Abstract Background Studies have shown that university/college students tend to have an exaggerated view of the quantities of alcohol being consumed by their peers. Making students aware of this misperception may help change behaviour and reduce problem drinking. Methods/Design A Solomon Three Group Design will be used. There is one intervention group and two control groups, controlling separately for measurement and for intervention effects. Recruitment, consent, randomisation and data collection are all on-line. The primary outcomes are AUDIT Score, weekly consumption, perceived social norms, and alcohol related problems; secondary outcomes include alcohol expectancies and other health behaviours. Discussion This trial will provide information on the effectiveness of an on-line personalized normative feedback intervention for alcohol misuse in university students. Trial registration International Standard Randomised Controlled Trial Number: ISRCTN30784467
Vries, N.M. de; Staal, J.B.; Teerenstra, S.; Adang, E.M.M.; Olde Rikkert, M.G.; Nijhuis-Van der Sanden, M.W.
2013-01-01
BACKGROUND: Older adults can benefit from physical activity in numerous ways. Physical activity is considered to be one of the few ways to influence the level of frailty. Standardized exercise programs do not necessarily lead to more physical activity in daily life, however, and a more personalized approach seems appropriate. The main objective of this study is to investigate whether a focused, problem-oriented coaching intervention ('Coach2Move') delivered by a physiotherapist specializing i...
Edgington, Eugene
2007-01-01
Statistical Tests That Do Not Require Random Sampling Randomization Tests Numerical Examples Randomization Tests and Nonrandom Samples The Prevalence of Nonrandom Samples in Experiments The Irrelevance of Random Samples for the Typical Experiment Generalizing from Nonrandom Samples Intelligibility Respect for the Validity of Randomization Tests Versatility Practicality Precursors of Randomization Tests Other Applications of Permutation Tests Questions and Exercises Notes References Randomized Experiments Unique Benefits of Experiments Experimentation without Mani
Xiaomei Qi
2012-01-01
Full Text Available A robust fault-tolerant controller design problem for networked control system (NCS with random packet dropout in both sensor-to-controller link and controller-to-actuator link is investigated. A novel stochastic NCS model with state-delay, model uncertainty, disturbance, probabilistic sensor failure, and actuator failure is proposed. The random packet dropout, sensor failures, and actuator failures are characterized by a binary random variable. The sufficient condition for asymptotical mean-square stability of NCS is derived and the closed-loop NCS satisfies H∞ performance constraints caused by the random packet dropout and disturbance. The fault-tolerant controller is designed by solving a linear matrix inequality. A numerical example is presented to illustrate the effectiveness of the proposed method.
Wang, Charles H -T; Bingham, Robert; Mendonca, J Tito
2008-01-01
We investigate the problem of metric fluctuations in the presence of the vacuum fluctuations of matter fields and critically assess the usual assertion that vacuum energy implies a Planckian cosmological constant. A new stochastic classical approach to the quantum fluctuations of spacetime is developed. The work extends conceptually Boyer's random electrodynamics to a theory of random gravity but has a considerably richer structure for inheriting nonlinearity from general relativity. Attention is drawn to subtleties in choosing boundary conditions for metric fluctuations in relation to their dynamical consequences. Those compatible with the observed Lorentz invariance must allow for spontaneous conformal fluctuations, in addition to stochastic gravitational waves due to zero point gravitons. This is implemented through an effective metric defined in terms of the random spacetime metric modulo a fluctuating conformal factor. It satisfies an effective Einstein equation coupled to an effective stress-energy tens...
Nikolopoulou, Maria; Byraki, Anna; Ahlberg, Jari; Heymans, Martijn W; Hamburger, H L; De Lange, Jan; Lobbezoo, Frank; Aarab, Ghizlane
2017-03-10
Obstructive sleep apnea syndrome (OSAS) is associated with several sleep disorders and sleep-related problems. Therefore, the aim of this study was to compare the effects of a mandibular advancement device (MAD) with those of nasal continuous positive airway pressure (nCPAP) on self-reported symptoms of common sleep disorders and sleep-related problems in mild and moderate OSAS patients. In this randomized placebo-controlled trial sixty-four OSAS patients (52.0± 9.6 years) were randomly assigned to an MAD, nCPAP or an intra-oral placebo appliance in a parallel design. All participants filled out the validated Dutch Sleep Disorders Questionnaire (SDQ) twice: one before treatment and one after six months of treatment. With 88 questions, thirteen scales were constructed, representing common sleep disorders and sleep-related problems. Linear mixed model analyses were performed to study differences between the groups for the different SDQ scales over time. The MAD group showed significant improvements over time in symptoms corresponding with "insomnia", "excessive daytime sleepiness", "psychiatric sleep disorder", "periodic limb movements", "sleep apnea", "sleep paralysis", "daytime dysfunction", "hypnagogic hallucinations/dreaming", "restless sleep", "negative conditioning", and "automatic behaviour" (range of P values: 0.000-0.014). These improvements in symptoms were, however, not significantly different from the improvements in symptoms observed in the nCPAP and placebo groups (range of P values: 0.090-0.897). It can be concluded that there is no significant difference between MAD and nCPAP in their positive effects on self-reported symptoms of common sleep disorders and sleep-related problems in mild and moderate OSAS patients. These beneficial effects may be a result of placebo effects. This article is protected by copyright. All rights reserved.
Lindahl, Bernt; Nilssön, Torbjörn K; Borch-Johnsen, Knut;
2009-01-01
AIMS: To compare data on cardiovascular risk factor changes in lipids, insulin, proinsulin, fibrinolysis, leptin and C-reactive protein, and on diabetes incidence, in relation to changes in lifestyle. METHODS: The study was a randomized lifestyle intervention trial conducted in northern Sweden...... with a single counselling session. Follow-up was conducted at 1, 3 and 5 years. RESULTS: At 1-year follow-up, an extensive cardio-metabolic risk factor reduction was demonstrated in the intensive intervention group, along with a 70% decrease of progress to type 2 diabetes. At 5-year follow-up, most...... of these beneficial effects had disappeared. Reported physical activity and fibre intake as well as high-density lipoprotein cholesterol were still increased, and fasting insulin and proinsulin were lower. CONCLUSIONS: The intervention affected several important cardio-metabolic risk variables beneficially...
Kinetochore-microtubule attachment is sufficient to satisfy the human spindle assembly checkpoint.
Etemad, Banafsheh; Kuijt, Timo E F; Kops, Geert J P L
2015-12-01
The spindle assembly checkpoint (SAC) is a genome surveillance mechanism that protects against aneuploidization. Despite profound progress on understanding mechanisms of its activation, it remains unknown what aspect of chromosome-spindle interactions is monitored by the SAC: kinetochore-microtubule attachment or the force generated by dynamic microtubules that signals stable biorientation of chromosomes? To answer this, we uncoupled these two processes by expressing a non-phosphorylatable version of the main microtubule-binding protein at kinetochores (HEC1-9A), causing stabilization of incorrect kinetochore-microtubule attachments despite persistent activity of the error-correction machinery. The SAC is fully functional in HEC1-9A-expressing cells, yet cells in which chromosomes cannot biorient but are stably attached to microtubules satisfy the SAC and exit mitosis. SAC satisfaction requires neither intra-kinetochore stretching nor dynamic microtubules. Our findings support the hypothesis that in human cells the end-on interactions of microtubules with kinetochores are sufficient to satisfy the SAC without the need for microtubule-based pulling forces.
Lu Wang,Qinghua Xing,; Yifan Mao
2015-01-01
To rapidly generate a reentry trajectory for hyper-sonic vehicle satisfying waypoint and no-fly zone constraints, a novel optimization method, which combines the improved parti-cle swarm optimization (PSO) algorithm with the improved Gauss pseudospectral method (GPM), is proposed. The improved PSO algorithm is used to generate a good initial value in a short time, and the mission of the improved GPM is to find the final solution with a high precision. In the improved PSO algorithm, by control-ling the entropy of the swarm in each dimension, the typical PSO algorithm’s weakness of being easy to fal into a local optimum can be overcome. In the improved GPM, two kinds of breaks are introduced to divide the trajectory into multiple segments, and the distribution of the Legendre-Gauss (LG) nodes can be altered, so that al the constraints can be satisfied strictly. Thereby the advan-tages of both the intel igent optimization algorithm and the direct method are combined. Simulation results demonstrate that the proposed method is insensitive to initial values, and it has more rapid convergence and higher precision than traditional ones.
2010-07-01
... be satisfied before an Executive agency may exercise the delegated authority to perform an individual... PROPERTY 72-DELEGATION OF AUTHORITY Delegation of Authority § 102-72.68 What preconditions must be satisfied before an Executive agency may exercise the delegated authority to perform an individual ancillary...
ON THE EXACT HAUSDORFF MEASURE OF A CLASS OF SELF-SIMILAR SETS SATISFYING OPEN SET CONDITION
Shaoyuan Xu; Weiyi Su; Zuoling Zhou
2008-01-01
In this paper,we provide a new effective method for computing the exact value of Hausdorff measures of a class of self-similar sets satisfying the open set condition(OSC).As applications,we discuss a self-similar Cantor set satisfying OSC and give a simple method for computing its exact Hausdorff measure.
Tennant, Ruhamah G.; Martin, Katie K.; Rooney, Rosanna; Hassan, Sharinaz; Kane, Robert T.
2017-01-01
Anxiety and depression are common mental health problems experienced by children in Australia. The impact of these internalizing disorders is pervasive, affecting many areas of life. By the time problems have been detected in children they can be severe in nature and harder to treat. Hence, early intervention is of utmost importance. Despite the existence of numerous prevention programs for children, there is limited empirical evidence for a program that has an impact on symptoms of both anxiety and depression. Physical activity and improved motor coordination have been indicated as having positive effects on children's mental health, although the impact of including these in a program targeting internalizing disorders has not been established. This study aimed to evaluate the efficacy of the Feelings and Friends (Year 3) program (FFY3), revised to include activities to build motor-coordination and encourage physical activity. Participants were 24 children from the Perth metropolitan area alongside one of each of their parents. Results indicated significant short-term intervention effects on one of the primary outcome variables; intervention group parents reported significant pre-post improvement in child depressive symptoms, which were maintained at 3-month follow-up (ηp2 = 0.10). There were also intervention effects observed for parent-reported separation anxiety (ηp2 = 0.10), externalizing symptoms (ηp2 = 0.19), and conduct problems (ηp2 = 0.16). An additional finding indicated the intervention students reported significant improvement from session one to session two in global distress (ηp2 = 0.22). No other significant intervention effects were evident. Findings from this study indicate that FFY3 is a promising intervention to address internalizing and externalizing symptoms in 8–9 year-old children. PMID:28326047
A Memetic Algorithm for the Capacitated Location-Routing Problem
Laila KECHMANE
2016-06-01
Full Text Available In this paper, a hybrid genetic algorithm is proposed to solve a Capacitated Location-Routing Problem. The objective is to minimize the total cost of the distribution in a network composed of depots and customers, both depots and vehicles have limited capacities, each depot has a homogenous vehicle fleet and customers’ demands are known and must be satisfied. Solving this problem involves making strategic decisions such as the location of depots, as well as tactical and operational decisions which include assigning customers to the opened depots and organization of the vehicle routing. To evaluate the performance of the proposed algorithm, its results are compared to those obtained by a greedy randomized adaptive search procedure, computational results shows that the algorithm gave good quality solutions.
吴臻; 王向荣
2003-01-01
给出一类布朗运动和泊松过程混合驱动的正倒向随机微分方程解的存在唯一性结果,应用这一结果研究带有随机跳跃干扰的线性二次随机最优控制问题,并得到最优控制的显式形式,可以证明最优控制是唯一的.然后,引入和研究一类推广的黎卡提方程系统,讨论该方程系统的可解性并由该方程的解得到带有随机跳跃干扰的线性二次随机最优控制问题最优的线性反馈.%One kind of existence and uniqueness result of forward-backward stochastic differential equations with Brownian motion and Poisson process is given. The result is applied to get the explicit form of the optimal control for linear quadratic stochastic optimal control problem with random jumps. The optimal control can be proved to be unique. One kind of generalized Riccati equation system is introduced and its solvability is discussed. The linear feedback regulator for the optimal control problem with random jump is given by the solution of the generalized Riccati equation system
Dynamical invariance for random matrices
Unterberger, Jeremie
2016-01-01
We consider a general Langevin dynamics for the one-dimensional N-particle Coulomb gas with confining potential $V$ at temperature $\\beta$. These dynamics describe for $\\beta=2$ the time evolution of the eigenvalues of $N\\times N$ random Hermitian matrices. The equilibrium partition function -- equal to the normalization constant of the Laughlin wave function in fractional quantum Hall effect -- is known to satisfy an infinite number of constraints called Virasoro or loop constraints. We introduce here a dynamical generating function on the space of random trajectories which satisfies a large class of constraints of geometric origin. We focus in this article on a subclass induced by the invariance under the Schr\\"odinger-Virasoro algebra.
Musielak-Orlicz-Hardy Spaces Associated with Operators Satisfying Reinforced Off-Diagonal Estimates
Bui The Anh
2013-02-01
Full Text Available Let X be a metric space with doubling measure and L a one-to-one operator of type ω having a bounded H∞ -functional calculus in L2(X satisfying the reinforced (pL; qL off-diagonal estimates on balls, where pL ∊ [1; 2 and qL ∊ (2;∞]. Let φ : X × [0;∞ → [0;∞ be a function such that φ (x;· is an Orlicz function, φ(·;t ∊ A∞(X (the class of uniformly Muckenhoupt weights, its uniformly critical upper type index l(φ ∊ (0;1] and φ(·; t satisfies the uniformly reverse Hölder inequality of order (qL/l(φ′, where (qL/l(φ′ denotes the conjugate exponent of qL/l(φ. In this paper, the authors introduce a Musielak-Orlicz-Hardy space Hφ;L(X, via the Lusin-area function associated with L, and establish its molecular characterization. In particular, when L is nonnegative self-adjoint and satisfies the Davies-Gaffney estimates, the atomic characterization of Hφ,L(X is also obtained. Furthermore, a sufficient condition for the equivalence between Hφ,L(ℝn and the classical Musielak-Orlicz-Hardy space Hv(ℝn is given. Moreover, for the Musielak-Orlicz-Hardy space Hφ,L(ℝn associated with the second order elliptic operator in divergence form on ℝn or the Schrödinger operator L := −Δ + V with 0 ≤ V ∊ L1loc(ℝn, the authors further obtain its several equivalent characterizations in terms of various non-tangential and radial maximal functions; finally, the authors show that the Riesz transform ∇L−1/2 is bounded from Hφ,L(ℝn to the Musielak-Orlicz space Lφ(ℝn when i(φ ∊ (0; 1], from Hφ,L(ℝn to Hφ(ℝn when i(φ ∊ (; 1], and from Hφ,L(ℝn to the weak Musielak-Orlicz-Hardy space WHφ(ℝn when i(φ=is attainable and φ(·; t ∊ A1(X, where i(φ denotes the uniformly critical lower type index of φ
Randomness: quantum versus classical
Khrennikov, Andrei
2015-01-01
Recent tremendous development of quantum information theory led to a number of quantum technological projects, e.g., quantum random generators. This development stimulates a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is elaboration of a consistent and commonly accepted interpretation of quantum state. Closely related problem is clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. The second part of this review is devoted to the information interpretation of quantum mechanics (QM) in the spirit of Zeilinger and Brukner (and QBism of Fuchs et al.) and physics in general (e.g., Wheeler's "it from bit") as well as digital philosophy of Chaitin (with historical coupling to ideas of Leibnitz). Finally, w...
Randomness: Quantum versus classical
Khrennikov, Andrei
2016-05-01
Recent tremendous development of quantum information theory has led to a number of quantum technological projects, e.g. quantum random generators. This development had stimulated a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is the elaboration of a consistent and commonly accepted interpretation of a quantum state. Closely related problem is the clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review, we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. We also discuss briefly “digital philosophy”, its role in physics (classical and quantum) and its coupling to the information interpretation of quantum mechanics (QM).
Analyzing Walksat on random formulas
Coja-Oghlan, Amin
2011-01-01
Let F be a uniformly distributed random k-SAT formula with n variables and m clauses. We prove that the Walksat algorithm from Papadimitriou (FOCS 1991)/Schoning (FOCS 1999) finds a satisfying assignment of F in polynomial time w.h.p. if m/n0. This is an improvement by a factor of $\\Theta(k)$ over the best previous analysis of Walksat from Coja-Oghlan, Feige, Frieze, Krivelevich, Vilenchik (SODA 2009).
Unified heuristics to solve routing problem of reverse logistics in sustainable supply chain
Anbuudayasankar, S. P.; Ganesh, K.; Lenny Koh, S. C.; Mohandas, K.
2010-03-01
A reverse logistics problem, motivated by many real-life applications, is examined where bottles/cans in which products are delivered from a processing depot to customers in one period are available for return to the depot in the following period. The picked-up bottles/cans need to be adjusted in the place of delivery load. This problem is termed as simultaneous delivery and pick-up problem with constrained capacity (SDPC). We develop three unified heuristics based on extended branch and bound heuristic, genetic algorithm and simulated annealing to solve SDPC. These heuristics are also designed to solve standard travelling salesman problem (TSP) and TSP with simultaneous delivery and pick-up (TSDP). We tested the heuristics on standard, derived and randomly generated datasets of TSP, TSDP and SDPC and obtained satisfying results with high convergence in reasonable time.
The existence of inflection points for generalized log-aesthetic curves satisfying G1 data
Karpagavalli, R.; Gobithaasan, R. U.; Miura, K. T.; Shanmugavel, Madhavan
2015-12-01
Log-Aesthetic (LA) curves have been implemented in a CAD/CAM system for various design feats. LA curves possess linear Logarithmic Curvature Graph (LCG) with gradient (shape parameter) denoted as α. In 2009, a generalized form of LA curves called Generalized Log-Aesthetic Curves (GLAC) has been proposed which has an extra shape parameter as ν compared to LA curves. Recently, G1 continuous GLAC algorithm has been proposed which utilizes the extra shape parameter using four control points. This paper discusses on the existence of inflection points in a GLAC segment satisfying G1 Hermite data and the effect of inflection point on convex hull property. It is found that the existence of inflection point can be avoided by manipulating the value of α. Numerical experiments show that the increase of α may remove the inflection point (if any) in a GLAC segment.
Emma Zang
2016-09-01
Full Text Available How and to what extent is rank mobility associated with happiness of the Chinese population? Does mobility provide insight into the vast numbers of frustrated workers in times of economic growth? To date, few studies have examined the consequences of social mobility on happiness in transitional societies. The present analysis investigates the association of both inter- and intragenerational rank mobility with happiness in China using data from the General Social Survey's 2003, 2006, and 2008 waves. We examine two general mechanisms, social adaptation and social comparison, by statistically decomposing the independent contributions of social origin, social destination, and mobility. We find there is a significant positive association between short-distance intragenerational downward mobility and happiness, while not any intergenerational mobility pattern has been found to be significant. Apparently, we have a group of satisfied losers. Our findings favor social comparison explanations.
Zweig-rule-satisfying inelastic rescattering in B decays to pseudoscalar mesons
Lach, P
2002-01-01
We discuss all contributions from Zweig-rule-satisfying SU(3)-symmetric inelastic FSI-induced corrections in B decays to $\\pi \\pi$, $\\pi K$, $K\\bar{K}$, $\\pi \\eta (\\eta ')$, and $K \\eta (\\eta ')$ . It is shown how all of these FSI corrections lead to a simple redefinition of the amplitudes, permitting the use of a simple diagram-based description, in which, however, weak phases may enter in a modified way. The inclusion of FSI corrections admitted by the present data allows an arbitrary relative phase between the penguin and tree short-distance amplitudes. The FSI-induced error of the method, in which the value of the weak phase $\\gamma $ is to be determined by combining future results from $B^+,B^0_d,B^0_s$ decays to $K\\pi$, is estimated to be of the order of $5^o$ for $\\gamma \\approx 50^o-60^o$.
Structure-Based Local Search Heuristics for Circuit-Level Boolean Satisfiability
Belov, Anton
2011-01-01
This work focuses on improving state-of-the-art in stochastic local search (SLS) for solving Boolean satisfiability (SAT) instances arising from real-world industrial SAT application domains. The recently introduced SLS method CRSat has been shown to noticeably improve on previously suggested SLS techniques in solving such real-world instances by combining justification-based local search with limited Boolean constraint propagation on the non-clausal formula representation form of Boolean circuits. In this work, we study possibilities of further improving the performance of CRSat by exploiting circuit-level structural knowledge for developing new search heuristics for CRSat. To this end, we introduce and experimentally evaluate a variety of search heuristics, many of which are motivated by circuit-level heuristics originally developed in completely different contexts, e.g., for electronic design automation applications. To the best of our knowledge, most of the heuristics are novel in the context of SLS for S...
Affective responses of high and low body satisfied men to viewing physique slides.
Hausenblas, Heather A; Janelle, Christopher M; Gardner, Rebecca Ellis; Hagan, Amy L
2003-01-01
The purpose of this study was to examine the acute affective responses of high and low body satisfied (BS) men who viewed physique slides of the male ideal (model-slides), physique slides of themselves (self-slides), and nonphysique slides (control-slides). During three laboratory visits the participants viewed the slides from one of the three conditions, and they completed pre-, in-, and post-task affective measures. It was found that the: (a) high BS group reported less mood disturbance than the low BS group; (b) participants reported an increase in depression, anger, and body dissatisfaction after viewing the self-slides; (c) participants indicated a decrease in body dissatisfaction after viewing the model-slides; and (d) viewing the control-slides did not result in affective changes. Findings suggest that viewing physique slides results in increased mood disturbance, regardless of BS level.
Two chiral preon models with SU(N) metacolor satisfying complementarity
Geng, C. Q.; Marshak, R. E.
1987-04-01
We have constructed two chiral preon models based on the group SU(N)MC×SU(N+4)F×U(1)F (MC is gauged metacolor and F is global color flavor), the simplest (M=0) version of a class of models SU(N)MC×SU(N+M+4)F×SU(M)F×U(1)F 2 studied by bars and Yankielowicz. In contrast with earlier work, our models satisfy the principle of complementarity between the Higgs and confining phases. In one model, N=16 and four generations of ordinary quarks and leptons are found at the gauged SO(10) level. The second model predicts three quark-lepton families at the gauged SU(5) level without a right-handed neutrino. We also show that complementarity holds for the M≠0 models but that, for N=15 or 16, the results at the gauged level are identical with the M=0 case.
Liu, Da-Yan
2015-04-30
This paper aims at designing a digital fractional order differentiator for a class of signals satisfying a linear differential equation to estimate fractional derivatives with an arbitrary order in noisy case, where the input can be unknown or known with noises. Firstly, an integer order differentiator for the input is constructed using a truncated Jacobi orthogonal series expansion. Then, a new algebraic formula for the Riemann-Liouville derivative is derived, which is enlightened by the algebraic parametric method. Secondly, a digital fractional order differentiator is proposed using a numerical integration method in discrete noisy case. Then, the noise error contribution is analyzed, where an error bound useful for the selection of the design parameter is provided. Finally, numerical examples illustrate the accuracy and the robustness of the proposed fractional order differentiator.
ON THE SECOND GREEDY WEIGHT FOR LINEAR CODES SATISFYING THE FULLRANK CONDITION
CHEN Wende; KLφVE Torleiv
2005-01-01
The maximum of g2 - d2 for linear [n, k, d; q] codes C is studied. Here d2 is the smallest size of the support of 2-dimensional subcodes of C and g2 is the smallest size of the support of 2-dimensional subcodes of C which contains a codeword of weight d. The extra cost to the greedy adversary to get two symbols of inform ation using some algorithmis g2 - d2. For codes satisfying the fullrank condition of general dimensions, upper bounds on the maximum of g2 - d2 are given. Under some condition we have got code C where g2 - d2 reaches the upper bound.
Piper, Llewellyn E; Tallman, Erin
2016-01-01
This article examines the parameters and the dynamics of Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) that create an ethical leadership dilemma to satisfy patients in the hospital setting while still ensuring appropriate care for quality clinical outcomes. Under the Affordable Care Act, hospitals and health care systems are in a high-stakes struggle of winners and losers based on HCAHPS scores. This high-stakes struggle creates unintended consequences of an ethical dilemma of doing what is right for the patient versus doing whatever it takes to please the patient in order to achieve high scores of satisfaction that are tied to better reimbursements. This article also reports the results of a national survey of 500 chief executive officers by the authors about the attitudes and frustrations of chief executive officers confronting the wild unrest caused by HCAHPS.
A Black-Scholes Approach to Satisfying the Demand in a Failure-Prone Manufacturing System
Chavez-Fuentes, Jorge R.; Gonzalex, Oscar R.; Gray, W. Steven
2007-01-01
The goal of this paper is to use a financial model and a hedging strategy in a systems application. In particular, the classical Black-Scholes model, which was developed in 1973 to find the fair price of a financial contract, is adapted to satisfy an uncertain demand in a manufacturing system when one of two production machines is unreliable. This financial model together with a hedging strategy are used to develop a closed formula for the production strategies of each machine. The strategy guarantees that the uncertain demand will be met in probability at the final time of the production process. It is assumed that the production efficiency of the unreliable machine can be modeled as a continuous-time stochastic process. Two simple examples illustrate the result.
Lüchow, Arne, E-mail: luechow@rwth-aachen.de [Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen (Germany); Jülich Aachen Research Alliance (JARA-HPC), 52056 Aachen (Germany); Sturm, Alexander; Schulte, Christoph; Haghighi Mood, Kaveh [Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen (Germany)
2015-02-28
Jastrow correlation factors play an important role in quantum Monte Carlo calculations. Together with an orbital based antisymmetric function, they allow the construction of highly accurate correlation wave functions. In this paper, a generic expansion of the Jastrow correlation function in terms of polynomials that satisfy both the electron exchange symmetry constraint and the cusp conditions is presented. In particular, an expansion of the three-body electron-electron-nucleus contribution in terms of cuspless homogeneous symmetric polynomials is proposed. The polynomials can be expressed in fairly arbitrary scaling function allowing a generic implementation of the Jastrow factor. It is demonstrated with a few examples that the new Jastrow factor achieves 85%–90% of the total correlation energy in a variational quantum Monte Carlo calculation and more than 90% of the diffusion Monte Carlo correlation energy.
Kang Shin
2011-01-01
Full Text Available Abstract In this paper, the existence, uniqueness and iterative approximations of fixed points for contractive mappings of integral type in complete metric spaces are established. As applications, the existence, uniqueness and iterative approximations of solutions for a class of functional equations arising in dynamic programming are discussed. The results presented in this paper extend and improve essentially the results of Branciari (A fixed point theorem for mappings satisfying a general contractive condition of integral type. Int. J. Math. Math. Sci. 29, 531-536, 2002, Kannan (Some results on fixed points. Bull. Calcutta Math. Soc. 60, 71-76, 1968 and several known results. Four concrete examples involving the contractive mappings of integral type with uncountably many points are constructed. 2010 Mathematics Subject Classfication: 54H25, 47H10, 49L20, 49L99, 90C39
A NEW VISION IN SALES: SATISFYING CUSTOMER NEEDS AND SOCIAL RESPONSIBILITY
Ion Stancu
2015-09-01
Full Text Available The new vision in sales requires, among other things, changing the salespeople's position towards the potential client by applying a philosophy that involves taking into consideration the people they come into contact with and providing solutions to address their needs in a disinterested manner, without having to pretend reciprocity. All this must be based on the concept of total sales utility, solutions to solve clients' immediate needs: the urgent ones, those who are directly related to them (financial needs, but also those arising from the use of goods purchased by the seller. The purpose of this article is to analyse how easily we can discover clients' real needs; under what conditions these needs can be satisfied through sales activities, and which the social responsibilities of the salespeople are.
Artur eDomurat
2015-08-01
Full Text Available This paper has two aims. First, we investigate how often people make choices conforming to Bayes’ rule when natural sampling is applied. Second, we show that using Bayes’ rule is not necessary to make choices satisfying Bayes’ rule. Simpler methods, even fallacious heuristics, might prescribe correct choices reasonably often under specific circumstances. We considered elementary situations with binary sets of hypotheses and data. We adopted an ecological approach and prepared two-stage computer tasks resembling natural sampling. Probabilistic relations were to be inferred from a set of pictures, followed by a choice between the data which was made to maximize a chance for a preferred outcome. Using Bayes’ rule was deduced indirectly from choices.Study 1 (N=60 followed a 2 (gender: female vs. male x 2 (education: humanities vs. pure sciences between-subjects factorial design with balanced cells, and a number of correct choices as a dependent variable. Choices satisfying Bayes’ rule were dominant. To investigate ways of making choices more directly, we replicated Study 1, adding a task with a verbal report. In Study 2 (N=76 choices conforming to Bayes’ rule dominated again. However, the verbal reports revealed use of a new, non-inverse rule, which always renders correct choices, but is easier than Bayes’ rule to apply. It does not require inversing conditions (transforming P(H and P(D|H into P(H|D when computing chances. Study 3 examined efficiency of the three fallacious heuristics (pre-Bayesian, representativeness, and evidence-only in producing choices concordant with Bayes’ rule. Computer-simulated scenarios revealed that the heuristics produce correct choices reasonably often under specific base rates and likelihood ratios. Summing up we conclude that natural sampling leads to most choices conforming to Bayes’ rule. However, people tend to replace Bayes’ rule with simpler methods, and even use of fallacious heuristics may
Scheltens Philip
2010-02-01
Full Text Available Abstract Background Depression frequently occurs in the elderly and in patients suffering from dementia. Its cause is largely unknown, but several studies point to a possible contribution of circadian rhythm disturbances. Post-mortem studies on aging, dementia and depression show impaired functioning of the suprachiasmatic nucleus (SCN which is thought to be involved in the increased prevalence of day-night rhythm perturbations in these conditions. Bright light enhances neuronal activity in the SCN. Bright light therapy has beneficial effects on rhythms and mood in institutionalized moderate to advanced demented elderly. In spite of the fact that this is a potentially safe and inexpensive treatment option, no previous clinical trial evaluated the use of long-term daily light therapy to prevent worsening of sleep-wake rhythms and depressive symptoms in early to moderately demented home-dwelling elderly. Methods/Design This study investigates whether long-term daily bright light prevents worsening of sleep-wake rhythms and depressive symptoms in elderly people with memory complaints. Patients with early Alzheimer's Disease (AD, Mild Cognitive Impairment (MCI and Subjective Memory Complaints (SMC, between the ages of 50 and 75, are included in a randomized double-blind placebo-controlled trial. For the duration of two years, patients are exposed to ~10,000 lux in the active condition or ~300 lux in the placebo condition, daily, for two half-hour sessions at fixed times in the morning and evening. Neuropsychological, behavioral, physiological and endocrine measures are assessed at baseline and follow-up every five to six months. Discussion If bright light therapy attenuates the worsening of sleep-wake rhythms and depressive symptoms, it will provide a measure that is easy to implement in the homes of elderly people with memory complaints, to complement treatments with cholinesterase inhibitors, sleep medication or anti-depressants or as a stand
2007-09-01
Guidance, Control, and Dynamics, 21(2):193–207, March-April 1998. 7. Betts, John T. “A Direct Approach to Solving Optimal Control Problems ,” CSE in...Paul. “Jacobi Pseudospectral Method for Solving Optimal Control Problems ,” Journal of Guidance, Control, and Dynamics, 27(2):293–297, 2004. 117
Shen, Hua
2016-10-19
A maximum-principle-satisfying space-time conservation element and solution element (CE/SE) scheme is constructed to solve a reduced five-equation model coupled with the stiffened equation of state for compressible multifluids. We first derive a sufficient condition for CE/SE schemes to satisfy maximum-principle when solving a general conservation law. And then we introduce a slope limiter to ensure the sufficient condition which is applicative for both central and upwind CE/SE schemes. Finally, we implement the upwind maximum-principle-satisfying CE/SE scheme to solve the volume-fraction-based five-equation model for compressible multifluids. Several numerical examples are carried out to carefully examine the accuracy, efficiency, conservativeness and maximum-principle-satisfying property of the proposed approach.
Measurement problem in PROGRAM UNIVERSE
Noyes, H.P.; Gefwert, C.
1984-12-01
We present a discrete theory that meets the measurement problem in a new way. We generate a growing universe of bit strings, labeled by 2/sup 127/ + 136 strings organized by some representation of the closed, four level, combinatorial hierarchy, of bit-length N/sub 139/ greater than or equal to 139. The rest of the strings for each label, which grow in both length and number, are called addresses. The generating algorithm, called PROGRAM UNIVERSE, starts from a random choice between the two symbols ''0'' and ''1'' and grows (a) by discriminating between two randomly chosen strings and adjoining a novel result to the universe, or when the string so generated is not novel, by (b) adjoining a randomly chosen bit at the growing end of each string. We obtain, by appropriate definitions and interpretations, stable ''particles'' which satisfy the usual relativistic kinematics and quantized angular momentum without being localizable in a continuum space-time. The labeling scheme is congruent with the ''standard model'' of quarks and leptons with three generations, but for the problem at hand, the implementation of this aspect of the theory is unimportant. What matters most is that (a) these complicated ''particles'' have the periodicities familiar from relativistic ''deBroglie waves'' and resolve in a discrete way the ''wave-particle dualism'' and (b) can be ''touched'' by our discrete equivalent of ''soft photons'' in such a way as to follow, macroscopically, the usual Rutherford scattering trajectories with the associated bound states. Thus our theory could provide a discrete description of ''measurement'' in a way that allows no conceptual barrier between the ''micro'' and the ''macro'' worlds, if we are willing to base our physics on
A QoS-Satisfied Prediction Model for Cloud-Service Composition Based on a Hidden Markov Model
Qingtao Wu; Mingchuan Zhang; Ruijuan Zheng; Ying Lou; Wangyang Wei
2013-01-01
Various significant issues in cloud computing, such as service provision, service matching, and service assessment, have attracted researchers’ attention recently. Quality of service (QoS) plays an increasingly important role in the provision of cloud-based services, by aiming for the seamless and dynamic integration of cloud-service components. In this paper, we focus on QoS-satisfied predictions about the composition of cloud-service components and present a QoS-satisfied prediction model b...
Random walks on reductive groups
Benoist, Yves
2016-01-01
The classical theory of Random Walks describes the asymptotic behavior of sums of independent identically distributed random real variables. This book explains the generalization of this theory to products of independent identically distributed random matrices with real coefficients. Under the assumption that the action of the matrices is semisimple – or, equivalently, that the Zariski closure of the group generated by these matrices is reductive - and under suitable moment assumptions, it is shown that the norm of the products of such random matrices satisfies a number of classical probabilistic laws. This book includes necessary background on the theory of reductive algebraic groups, probability theory and operator theory, thereby providing a modern introduction to the topic.
GUO TieXin; CHEN XinXiang
2009-01-01
The purpose of this paper is to provide a random duality theory for the further development of the theory of random conjugate spaces for random normed modules.First,the complicated stratification structure of a module over the algebra L(μ,K) frequently makes our investigations into random duality theory considerably different from the corresponding ones into classical duality theory,thus in this paper we have to first begin in overcoming several substantial obstacles to the study of stratification structure on random locally convex modules.Then,we give the representation theorem of weakly continuous canonical module homomorphisms,the theorem of existence of random Mackey structure,and the random bipolar theorem with respect to a regular random duality pair together with some important random compatible invariants.
无
2009-01-01
The purpose of this paper is to provide a random duality theory for the further development of the theory of random conjugate spaces for random normed modules. First, the complicated stratification structure of a module over the algebra L(μ, K) frequently makes our investigations into random duality theory considerably difierent from the corresponding ones into classical duality theory, thus in this paper we have to first begin in overcoming several substantial obstacles to the study of stratification structure on random locally convex modules. Then, we give the representation theorem of weakly continuous canonical module homomorphisms, the theorem of existence of random Mackey structure, and the random bipolar theorem with respect to a regular random duality pair together with some important random compatible invariants.
ZHU Xiao-cai; DONG Guo-hua; CAI Zi-xing; HU De-wen
2007-01-01
A robust unified controller was proposed for wheeled mobile robots that do not satisfy the ideal rolling without slipping constraint. Practical trajectory tracking and posture stabilization were achieved in a unified framework. The design procedure was based on the transverse function method and Lyapunov redesign technique. The Lie group was also introduced in the design. The left-invariance property of the nominal model was firstly explored with respect to the standard group operation of the Lie group SE(2). Then, a bounded transverse function was constructed, by which a corresponding smooth embedded submanifold was defined.With the aid of the group operation, a smooth control law was designed, which fulfills practical tracking/stabilization of the nominal system. An additional component was finally constructed to robustify the nominal control law with respect to the slipping disturbance by using the Lyapunov redesign technique. The design procedure can be easily extended to the robot system suffered from general unknown but bounded disturbances. Simulations were provided to demonstrate the effectiveness of the robust unified controller.
Einstein-Gauss-Bonnet traversable wormholes satisfying the weak energy condition
Mehdizadeh, Mohammad Reza; Lobo, Francisco S N
2015-01-01
In this paper, we explore higher-dimensional asymptotically flat wormhole geometries in the framework of Gauss-Bonnet (GB) gravity and investigate the effects of the GB term, by considering a specific radial-dependent redshift function and by imposing a particular equation of state. This work is motivated by previous assumptions that wormhole solutions were not possible for the $k=1$ and $\\alpha < 0$ case, where $k$ is the sectional curvature of an $(n-2)$-dimensional maximally symmetric space, and $\\alpha$ is the Gauss-Bonnet coupling constant. However, we emphasize that this discussion is purely based on a nontrivial assumption that is only valid at the wormhole throat, and cannot be extended to the entire radial-coordinate range. In this work, we provide a counterexample to this claim, and find for the first time specific solutions that satisfy the weak energy condition throughout the entire spacetime, for $k=1$ and $\\alpha < 0$. In addition to this, we also present other wormhole solutions which all...
Ketamine administration makes patients and physicians satisfied during gastro-enteric endoscopies
Saeed Majidinejad
2015-01-01
Full Text Available Background: A suitable sedative status during gastro-enteric endoscopies results in better physicians′ approach and more stable view of internal organs. Therefore, we evaluated the effect of ketamine for sedation in endoscopic procedures of adult patients. Materials and Methods: Patients who were candidates for gastro-enteric endoscopy during the years 2014-2015 were included into the study and divided into two groups of case (administered 5 mg/kg of oral ketamine half an hour before initiation of the procedure and control (administered placebo in a same pattern. After endoscopy, patients and physicians′ satisfaction of sedation was assessed. SPSS-22 was used for data analysis. Results: Eighty-six patients participated into the study of which divided into each groups. The pain and discomfort scores were 2.4 ± 1.8 and 5.81 ± 1.48 in case and control groups, respectively, (P < 0.001. Mann-Whitney test revealed statistical difference among groups about physician′s satisfaction of sedation during endoscopy (P < 0.001. Patients who received ketamine had better sedative status (P < 0.001. None of the patients in the case group was completely awake but all of the patients in the control group were awake. The number of retching during endoscopy showed that individuals in the control group had more frequent retching episodes (P = 0.04. Conclusion: Low-dose oral administration of ketamine could make a satisfied sedation for gastro-enteric endoscopy.
What makes nursing satisfying: a comparison of college students' and registered nurses' views.
Dodds, A E; Lawrence, J A; Wearing, A J
1991-06-01
This paper reports a study of nurses' perceptions of the positive and negative features of the work environment and their contribution to satisfaction with nursing. The concept of a 'work space' was developed to describe nurses' mental images of the features of their work environment. Eighty-four final-year student nurses and 75 registered nurses rated questionnaire items designed to examine perceptions of opportunities for professional development, sources of satisfaction, difficulties, time constraints and problematic interactions with other hospital personnel. There was general agreement among nurses about the aspects of their work that they found satisfying, but student nurses were more pessimistic than registered nurses that nursing would give them opportunities for recognition of their worth. Students returning from practica in critical care wards reported more stressful interactions with other personnel than students returning from general ward practica. Structural equation modelling of the causal relations between sources of satisfaction with nursing revealed that recognition and self-perceptions of work as a nurse were the strongest predictors of overall satisfaction with nursing. Caring for patients contributed only indirectly through its influence on nurses' feelings about themselves. The data indicate the significance of personal and social implications of nursing careers.
ITER components cooling: Satisfying the distinct needs of systems and components
Ployhar, Steven James, E-mail: steve.ployhar@iter.org [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul Lez Durance (France); Gopalapillai, Babulal; Teodoros, Liliana Cristina; Dell Orco, Giovanni [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul Lez Durance (France); Kumar, Ajith; Gupta, Dinesh; Patel, Nirav; Jadhav, Mahesh Ashok [ITER-India, Institute for Plasma Research, A-29, GIDC Electronic Estate, Sector-25, Gandhinagar 382016, Gujarat (India)
2014-10-15
The ITER Tokamak requires multiple auxiliary systems to initiate, support, and monitor the fusion reaction. Heat produced by these systems, as well as the heat produced by the fusion reaction itself is collected by the ITER Cooling Water System (CWS) and rejected to the atmosphere. The CWS is composed of several systems designed for specific cooling roles. One of these systems is the Component Cooling Water System 2 (CCWS-2) whose function is to collect the heat from auxiliary client systems and components and transfer it to the Heat Rejection System. Clients are located throughout the site and have different requirements in terms of pressure, temperature, temperature variation, flow, metallurgy of wetted surfaces, and water quality. To satisfy these different requirements the CCWS-2 is divided into four separate loops, each of which has different operating parameters. For example, the CCWS-2A loop is designed to cool components with wetted surfaces of copper and primarily serves the radio-frequency heating systems, magnet power supplies, and neutral beam injector system components. This paper describes the evolution of the CCWS-2 system to match the needs of groups of compatible clients, and describes the development of the preliminary design of one of its loops, CCWS-2A, to meet individual client needs.
Non-minimal coupling of torsion-matter satisfying null energy condition for wormhole solutions
Jawad, Abdul; Rani, Shamaila [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan)
2016-12-15
We explore wormhole solutions in a non-minimal torsion-matter coupled gravity by taking an explicit non-minimal coupling between the matter Lagrangian density and an arbitrary function of the torsion scalar. This coupling describes the transfer of energy and momentum between matter and torsion scalar terms. The violation of the null energy condition occurred through an effective energy-momentum tensor incorporating the torsion-matter non-minimal coupling, while normal matter is responsible for supporting the respective wormhole geometries. We consider the energy density in the form of non-monotonically decreasing function along with two types of models. The first model is analogous to the curvature-matter coupling scenario, that is, the torsion scalar with T-matter coupling, while the second one involves a quadratic torsion term. In both cases, we obtain wormhole solutions satisfying the null energy condition. Also, we find that the increasing value of the coupling constant minimizes or vanishes on the violation of the null energy condition through matter. (orig.)
LI Zuoyong; PENG Lihong
2004-01-01
This paper analyses the intrinsic relationship between the BP network learning ability and generalization ability and other influencing factors when the overfit occurs, and introduces the multiple correlation coefficient to describe the complexity of samples; it follows the calculation uncertainty principle and the minimum principle of neural network structural design, provides an analogy of the general uncertainty relation in the information transfer process, and ascertains the uncertainty relation between the training relative error of the training sample set, which reflects the network learning ability,and the test relative error of the test sample set, which represents the network generalization ability; through the simulation of BP network overfit numerical modeling test with different types of functions, it is ascertained that the overfit parameter q in the relation generally has a span of 7×10-3 to 7 × 10-2; the uncertainty relation then helps to obtain the formula for calculating the number of hidden nodes of a network with good generalization ability under the condition that multiple correlation coefficient is used to describe sample complexity and the given approximation error requirement is satisfied;the rationality of this formula is verified; this paper also points out that applying the BP network to the training process of the given sample set is the best method for stopping training that improves the generalization ability.
2010-01-01
We consider the problem of reinforcement learning in high-dimensional spaces when the number of features is bigger than the number of samples. In particular, we study the least-squares temporal difference (LSTD) learning algorithm when a space of low dimension is generated with a random projection from a high-dimensional space. We provide a thorough theoretical analysis of the LSTD with random projections and derive performance bounds for the resulting algorithm. We also show how the error of...
Kannisto, Kati Anneli; Korhonen, Joonas; Adams, Clive E; Koivunen, Marita Hannele; Vahlberg, Tero; Välimäki, Maritta Anneli
2017-02-21
Clinical trials are the gold standard of evidence-based practice. Still many papers inadequately report methodology in randomized controlled trials (RCTs), particularly for mHealth interventions for people with serious mental health problems. To ensure robust enough evidence, it is important to understand which study phases are the most vulnerable in the field of mental health care. We mapped the recruitment and the trial follow-up periods of participants to provide a picture of the dropout predictors from a mHealth-based trial. As an example, we used a mHealth-based multicenter RCT, titled "Mobile.Net," targeted at people with serious mental health problems. Recruitment and follow-up processes of the Mobile.Net trial were monitored and analyzed. Recruitment outcomes were recorded as screened, eligible, consent not asked, refused, and enrolled. Patient engagement was recorded as follow-up outcomes: (1) attrition during short message service (SMS) text message intervention and (2) attrition during the 12-month follow-up period. Multiple regression analysis was used to identify which demographic factors were related to recruitment and retention. We recruited 1139 patients during a 15-month period. Of 11,530 people screened, 36.31% (n=4186) were eligible. This eligible group tended to be significantly younger (mean 39.2, SD 13.2 years, Pintervention. Attrition from the SMS text message intervention was 4.8% (27/563). The patient dropout rate after 12 months was 0.36% (4/1123), as discovered from the register data. In all, 3.12% (35/1123) of the participants withdrew from the trial. However, dropout rates from the patient survey (either by paper or telephone interview) were 52.45% (589/1123) and 27.8% (155/558), respectively. Almost all participants (536/563, 95.2%) tolerated the intervention, but those who discontinued were more often women (21/27, 78%; P=.009). Finally, participants' age (P<.001), gender (P<.001), vocational education (P=.04), and employment status
Elgán Tobias H
2012-01-01
Full Text Available Abstract Background It has been estimated that approximately 20% of all Swedish children grow up with parents having alcohol problems, which may result in negative outcomes among these children. Therefore, most Swedish municipalities provide resources for support, but at the same time figures reveal that not even 2% receive support, mainly due to difficulties in identifying and recruiting these children into support programs. Delivering intervention programs to children and adolescents via the Internet seems a promising strategy, but to date, the number of web-based interventions aimed at this target group is very scarce. We have therefore developed a novel internet-delivered therapist assisted self-management intervention called the web-ICAIP (Individual Coping and Alcohol Intervention Program for adolescents having parents with alcohol problems. The purpose of the program is to strengthen adolescents' coping behavior, improve their mental health, and postponing the onset or decreasing risky alcohol consumption. This paper describes the web-ICAIP and the design of a randomized controlled trial (RCT to measure the efficacy of this intervention. Methods/Design The RCT will include at least 183 adolescents (15-19 year old who will be randomly allocated to two conditions where one group has access to the web-ICAIP and the other is a waiting list control group. Participants will be recruited from websites containing information and facts for adolescents about alcohol and other drugs. Possible participants will be screened using the short version of the Children of Alcoholics Screening Test (CAST-6. The assessment consists of a baseline and two follow-up measurements taking place after two and six months, respectively. The primary outcomes include the Center for Epidemiological Studies Depression Scale (CES-DC, a coping behavior scale, and also the short version of the Alcohol Use Disorders Identification Test (AUDIT-C. Additional outcomes include
Elgán, Tobias H; Hansson, Helena; Zetterlind, Ulla; Kartengren, Nicklas; Leifman, Håkan
2012-01-16
It has been estimated that approximately 20% of all Swedish children grow up with parents having alcohol problems, which may result in negative outcomes among these children. Therefore, most Swedish municipalities provide resources for support, but at the same time figures reveal that not even 2% receive support, mainly due to difficulties in identifying and recruiting these children into support programs. Delivering intervention programs to children and adolescents via the Internet seems a promising strategy, but to date, the number of web-based interventions aimed at this target group is very scarce. We have therefore developed a novel internet-delivered therapist assisted self-management intervention called the web-ICAIP (Individual Coping and Alcohol Intervention Program) for adolescents having parents with alcohol problems. The purpose of the program is to strengthen adolescents' coping behavior, improve their mental health, and postponing the onset or decreasing risky alcohol consumption. This paper describes the web-ICAIP and the design of a randomized controlled trial (RCT) to measure the efficacy of this intervention. The RCT will include at least 183 adolescents (15-19 year old) who will be randomly allocated to two conditions where one group has access to the web-ICAIP and the other is a waiting list control group. Participants will be recruited from websites containing information and facts for adolescents about alcohol and other drugs. Possible participants will be screened using the short version of the Children of Alcoholics Screening Test (CAST-6). The assessment consists of a baseline and two follow-up measurements taking place after two and six months, respectively. The primary outcomes include the Center for Epidemiological Studies Depression Scale (CES-DC), a coping behavior scale, and also the short version of the Alcohol Use Disorders Identification Test (AUDIT-C). Additional outcomes include the "Ladder of life" which measures overall life
A positive and entropy-satisfying finite volume scheme for the Baer-Nunziato model
Coquel, Frédéric; Hérard, Jean-Marc; Saleh, Khaled
2017-02-01
We present a relaxation scheme for approximating the entropy dissipating weak solutions of the Baer-Nunziato two-phase flow model. This relaxation scheme is straightforwardly obtained as an extension of the relaxation scheme designed in [16] for the isentropic Baer-Nunziato model and consequently inherits its main properties. To our knowledge, this is the only existing scheme for which the approximated phase fractions, phase densities and phase internal energies are proven to remain positive without any restrictive condition other than a classical fully computable CFL condition. For ideal gas and stiffened gas equations of state, real values of the phasic speeds of sound are also proven to be maintained by the numerical scheme. It is also the only scheme for which a discrete entropy inequality is proven, under a CFL condition derived from the natural sub-characteristic condition associated with the relaxation approximation. This last property, which ensures the non-linear stability of the numerical method, is satisfied for any admissible equation of state. We provide a numerical study for the convergence of the approximate solutions towards some exact Riemann solutions. The numerical simulations show that the relaxation scheme compares well with two of the most popular existing schemes available for the Baer-Nunziato model, namely Schwendeman-Wahle-Kapila's Godunov-type scheme [39] and Tokareva-Toro's HLLC scheme [44]. The relaxation scheme also shows a higher precision and a lower computational cost (for comparable accuracy) than a standard numerical scheme used in the nuclear industry, namely Rusanov's scheme. Finally, we assess the good behavior of the scheme when approximating vanishing phase solutions.
Iqbal, R; Dhiman, S; Sen, A K; Shen, Amy Q
2017-06-13
We report the dynamics of compound droplets with a denser liquid (water) droplet over a less dense sessile droplet (mineral oil) that satisfies the Neumann condition. For a fixed size of an oil droplet, depending on the size of the water droplet, either it attains the axisymmetric position or tends to migrate toward the edge of the oil droplet. For a water droplet-to-oil droplet at volume ratio Vw/Vo ≥ 0.05, stable axisymmetric configuration is achieved; for Vw/Vo droplet is observed. The stability and migration of water droplets of size above and below critical size, respectively, are explained using the force balance at the three-phase contact line and film tension. The larger and smaller droplets that initially attain the axisymmetric position or some radial position, respectively, evaporate continuously and thus migrate toward the edge of the oil droplet. The radial location and migration of the water droplets of different initial sizes with respect to time are studied. Experiments with water droplets on a flat oil-air interface did not show migration, which signified the role of the curved oil-air interface for droplet migration. Finally, coalescence of water droplets of size above the critical size at the axisymmetric position is demonstrated. Our compound droplet studies could be beneficial for applications involving droplet transport where contamination due to direct contact and pinning of droplets on solid surfaces is of concern. Migration and coalescence of water droplets on curved oil-air interfaces could open new frontiers in chemical and biological applications including multiphase processing and biological interaction of cells and atmospheric chemistry.
On the Fractality of Complex Networks: Covering Problem, Algorithms and Ahlfors Regularity
Wang, Lihong; Wang, Qin; Xi, Lifeng; Chen, Jin; Wang, Songjing; Bao, Liulu; Yu, Zhouyu; Zhao, Luming
2017-01-01
In this paper, we revisit the fractality of complex network by investigating three dimensions with respect to minimum box-covering, minimum ball-covering and average volume of balls. The first two dimensions are calculated through the minimum box-covering problem and minimum ball-covering problem. For minimum ball-covering problem, we prove its NP-completeness and propose several heuristic algorithms on its feasible solution, and we also compare the performance of these algorithms. For the third dimension, we introduce the random ball-volume algorithm. We introduce the notion of Ahlfors regularity of networks and prove that above three dimensions are the same if networks are Ahlfors regular. We also provide a class of networks satisfying Ahlfors regularity. PMID:28128289
The Obstacle Problem for the -Harmonic Equation
Bao Gejun
2010-01-01
Full Text Available Firstly, we define an order for differential forms. Secondly, we also define the supersolution and subsolution of the -harmonic equation and the obstacle problems for differential forms which satisfy the -harmonic equation, and we obtain the relations between the solutions to -harmonic equation and the solution to the obstacle problem of the -harmonic equation. Finally, as an application of the obstacle problem, we prove the existence and uniqueness of the solution to the -harmonic equation on a bounded domain with a smooth boundary , where the -harmonic equation satisfies where is any given differential form which belongs to .
邹涛; 李少远
2005-01-01
In this paper, the feasibility and objectives coordination of real-time optimization (RTO) are systemically investigated under soft constraints. The reason for requiring soft constraints adjustment and objective relaxation simultaneously is that the result is not satisfactory when the feasible region is apart from the desired working point or the optimization problem is infeasible. The mixed logic method is introduced to describe the priority of the constraints and objectives, thereby the soft constraints adjustment and objectives coordination are solved together in RTO. A case study on the Shell heavy oil fractionators benchmark problem illustrating the method is finally presented.
On complete moment convergence for nonstationary negatively associated random variables
Mi-Hwa Ko
2016-05-01
Full Text Available Abstract The purpose of this paper is to establish the complete moment convergence for nonstationary negatively associated random variables satisfying the weak mean domination condition. The result is an improvement of complete convergence in Marcinkiewicz-Zygmund-type SLLN for negatively associated random variables in Kuczmaszewska (Acta Math. Hung. 128:116-130, 2010.
Dynamic Restructuring Of Problems In Artificial Intelligence
Schwuttke, Ursula M.
1992-01-01
"Dynamic tradeoff evaluation" (DTE) denotes proposed method and procedure for restructuring problem-solving strategies in artificial intelligence to satisfy need for timely responses to changing conditions. Detects situations in which optimal problem-solving strategies cannot be pursued because of real-time constraints, and effects tradeoffs among nonoptimal strategies in such way to minimize adverse effects upon performance of system.
Statistical search methods for lotsizing problems
M. Salomon (Marc); R. Kuik (Roelof); L.N. van Wassenhove (Luk)
1993-01-01
textabstractThis paper reports on our experiments with statistical search methods for solving lotsizing problems in production planning. In lotsizing problems the main objective is to generate a minimum cost production and inventory schedule, such that (i) customer demand is satisfied, and (ii) capa
Interference-aware random beam selection for spectrum sharing systems
Abdallah, Mohamed M.
2012-09-01
Spectrum sharing systems have been introduced to alleviate the problem of spectrum scarcity by allowing secondary unlicensed networks to share the spectrum with primary licensed networks under acceptable interference levels to the primary users. In this paper, we develop interference-aware random beam selection schemes that provide enhanced throughput for the secondary link under the condition that the interference observed at the primary link is within a predetermined acceptable value. For a secondary transmitter equipped with multiple antennas, our schemes select a random beam, among a set of power- optimized orthogonal random beams, that maximizes the capacity of the secondary link while satisfying the interference constraint at the primary receiver for different levels of feedback information describing the interference level at the primary receiver. For the proposed schemes, we develop a statistical analysis for the signal-to-noise and interference ratio (SINR) statistics as well as the capacity of the secondary link. Finally, we present numerical results that study the effect of system parameters including number of beams and the maximum transmission power on the capacity of the secondary link attained using the proposed schemes. © 2012 IEEE.
Which young physicians are satisfied with their work? A prospective nationwide study in Norway
Ekeberg Oivind
2005-06-01
Full Text Available Abstract Background Few studies have investigated personality and medical school variables in regard to job satisfaction after graduation. It is of great importance to investigate these factors because this information may be used in the recruitment/admittance process to medical schools, and possibly to improve medical education. Methods We conducted a nationwide prospective 10-year follow-up study of medical students at all medical schools in Norway. They were approached three times during their medical training: at very beginning (T1, in the middle (T2, in the last year of medical school (T3, and then four years after graduation (T4. There were 210 participants who responded on all four occasions. Job satisfaction was measured with the Job Satisfaction Scale, which was used as the outcome variable. In addition to conducting multiple regression analysis for the total sample, we also conducted similar analyses separately for men and women. Results Among the demographic and personality variables, 'having a father who is a physician' and 'interpersonal functioning (being withdrawn' were significantly associated with job satisfaction at T4. Among the medical school variables, 'well-being with peers', 'identification with the doctor's role at the end of curriculum', 'perceived medical school stress', and 'perceived clinical skills' were significantly associated with job satisfaction. In the multiple regression analysis only 'father as a physician' and 'perceived clinical skills' yielded an independent influence on the outcome variable in separate analyses within sub-groups of male and female students, 'perceived clinical skills' differentiated among woman only, while 'well-being with peers' differentiated only among men. Conclusion The main finding of this study is that the young physicians who are the most satisfied in their work are those whose fathers are physicians and those who have a high level of perceived clinical skills at the end of
Satisfying values--yours and theirs: a talk with Manny Elkind. Interview by Richard L.Reece.
Elkind, M
1999-01-01
Richard Reece, MD, interviewed Mansfield (Manny) Elkind on September 22, 1999 to talk about satisfying values and flexible thinking as keys to influencing physicians. Manny discusses why it's difficult for people to create lasting change in the workplace without recreating themselves. The effort to influence others often focuses on getting disciplined about changing behaviors, with the hope that feelings and attitudes will also change. This approach rarely works because behavior is changed only when values or beliefs change. People will get passionate and committed to achieving the organization's goals when they believe that their values will be satisfied as well. The leader's responsibility is to find ways of satisfying people's values, in addition to convincing them to use the organization's values as guides for behavior. A process is explored that helps people discover each other's values and preferences and transforms resistance to commitment.
Are UK radiologists satisfied with the training and support received in suspected child abuse?
Leung, R.S. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom); Nwachuckwu, C. [Department of Paediatrics, Whipps Cross Hospital, London (United Kingdom); Pervaiz, A. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom); Wallace, C.; Landes, C. [Department of Radiology, Royal Liverpool Childrens NHS Trust, Liverpool (United Kingdom); Offiah, A.C. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom)], E-mail: OffiaA@gosh.nhs.uk
2009-07-15
Aim: To determine current practice and perceptions of the adequacy of training and support received for the reporting of skeletal surveys in suspected physical child abuse. Materials and methods: A list of telephone numbers of UK hospitals with a radiology department was obtained from Royal College of Radiologists. One hundred hospitals were then randomly selected for inclusion in the survey. An 18-item questionnaire was successfully administered to consultant radiologists from 84 departments. Results: Sixty-one percent of departments had a named radiologist to report their skeletal surveys, 16% assigned surveys to a random radiologist, and 23% referred them elsewhere. Only 52% of departments had a dedicated paediatric radiologist, thus in a significant proportion of departments (25%) initial reports on skeletal surveys for physical abuse were provided by non-paediatric radiologists. Fifteen percent did not have ready access to a paediatric radiology opinion. Sixty-one percent thought that the service could be improved. Expert evidence was provided by 5% of respondents. Seventy-three percent would never consider providing expert evidence, even if given adequate radiology and/or legal training. Conclusion: The survey shows significant dissatisfaction amongst consultant radiologists with the current service, confirms a low number of paediatric radiologists taking on this work, and suggests the potential to increase numbers of radiology child abuse experts by 27% if given improved training and support. Appropriate service and education strategies should be implemented.
Rhodes, Karin V; Rodgers, Melissa; Sommers, Marilyn; Hanlon, Alexandra; Crits-Christoph, Paul
2014-04-18
There is a strong reciprocal association between two highly prevalent public health problems: intimate partner violence and heavy drinking, both of which remain major sources of morbidity and mortality. Brief interventions in the Emergency Department setting have been found to be effective in reducing alcohol-related injury but neither classic intimate partner violence nor substance abuse interventions have adequately integrated assessment and treatment for these co-occurring conditions. The overall goal of this study is to determine whether a motivational intervention delivered at the time of an Emergency Department visit will reduce heavy drinking and improve the safety of women experiencing intimate partner violence. We are completing data collection for a randomized controlled trial enrolling 600 female patients, age 18-64, presenting to one of two urban Emergency Departments, who self-disclose both problem drinking and intimate partner violence. Eligible patients are randomized to a brief manual-guided motivational intervention, and a phone booster at 10 days. The intervention, which is delivered by masters-level therapists during the Emergency Department visit, is recorded and monitored for fidelity. Primary outcomes are episodes of heavy drinking and incidents of intimate partner violence, assessed weekly by Interactive Voice Response System for 12 weeks and at 3, 6 and 12 months by interviewers blinded to group assignment. To identify the impact of assessment alone, we included a no-contact control group assessed only once at 3 months. Secondary outcomes include violence severity, changes in the Composite Abuse Scale and alcohol quantity/frequency, along with other health-related behaviors. The analysis will also explore the impact of likely mediators and moderators of the intervention. While screening and intervention for intimate partner violence is now recommended for women of child bearing age in health care settings, there is a need for rigorous
Random processes in nuclear reactors
Williams, M M R
1974-01-01
Random Processes in Nuclear Reactors describes the problems that a nuclear engineer may meet which involve random fluctuations and sets out in detail how they may be interpreted in terms of various models of the reactor system. Chapters set out to discuss topics on the origins of random processes and sources; the general technique to zero-power problems and bring out the basic effect of fission, and fluctuations in the lifetime of neutrons, on the measured response; the interpretation of power reactor noise; and associated problems connected with mechanical, hydraulic and thermal noise sources
Christian Herrmann
2013-09-01
Full Text Available Nondeterministic polynomial-time Blum-Shub-Smale Machines over the reals give rise to a discrete complexity class between NP and PSPACE. Several problems, mostly from real algebraic geometry / polynomial systems, have been shown complete (under many-one reduction by polynomial-time Turing machines for this class. We exhibit a new one based on questions about expressions built from cross products only.
Wei, Peng; Sridhar, Banavar; Chen, Neil Yi-Nan; Sun, Dengfent
2012-01-01
A class of strategies has been proposed to reduce contrail formation in the United States airspace. A 3D grid based on weather data and the cruising altitude level of aircraft is adjusted to avoid the persistent contrail potential area with the consideration to fuel-efficiency. In this paper, the authors introduce a contrail avoidance strategy on 3D grid by considering additional operationally feasible constraints from an air traffic controller's aspect. First, shifting too many aircraft to the same cruising level will make the miles-in-trail at this level smaller than the safety separation threshold. Furthermore, the high density of aircraft at one cruising level may exceed the workload for the traffic controller. Therefore, in our new model we restrict the number of total aircraft at each level. Second, the aircraft count variation for successive intervals cannot be too drastic since the workload to manage climbing/descending aircraft is much larger than managing cruising aircraft. The contrail reduction is formulated as an integer-programming problem and the problem is shown to have the property of total unimodularity. Solving the corresponding relaxed linear programming with the simplex method provides an optimal and integral solution to the problem. Simulation results are provided to illustrate the methodology.
Kinsella, John J.
1970-01-01
Discussed are the nature of a mathematical problem, problem solving in the traditional and modern mathematics programs, problem solving and psychology, research related to problem solving, and teaching problem solving in algebra and geometry. (CT)
Zhou, Yu-Qian; Gao, Fei; Li, Dan-Dan; Li, Xin-Hui; Wen, Qiao-Yan
2016-09-01
We have proved that new randomness can be certified by partially free sources using 2 →1 quantum random access code (QRAC) in the framework of semi-device-independent (SDI) protocols [Y.-Q. Zhou, H.-W. Li, Y.-K. Wang, D.-D. Li, F. Gao, and Q.-Y. Wen, Phys. Rev. A 92, 022331 (2015), 10.1103/PhysRevA.92.022331]. To improve the effectiveness of the randomness generation, here we propose the SDI randomness expansion using 3 →1 QRAC and obtain the corresponding classical and quantum bounds of the two-dimensional quantum witness. Moreover, we get the condition which should be satisfied by the partially free sources to successfully certify new randomness, and the analytic relationship between the certified randomness and the two-dimensional quantum witness violation.
Partial match queries in random quadtrees
Broutin, Nicolas; Sulzbach, Henning
2011-01-01
We consider the problem of recovering items matching a partially specified pattern in multidimensional trees (quad trees and k-d trees). We assume the traditional model where the data consist of independent and uniform points in the unit square. For this model, in a structure on $n$ points, it is known that the number of nodes $C_n(\\xi)$ to visit in order to report the items matching an independent and uniformly on $[0,1]$ random query $\\xi$ satisfies $\\Ec{C_n(\\xi)}\\sim \\kappa n^{\\beta}$, where $\\kappa$ and $\\beta$ are explicit constants. We develop an approach based on the analysis of the cost $C_n(x)$ of any fixed query $x\\in [0,1]$, and give precise estimates for the variance and limit distribution of the cost $C_n(x)$. Our results permit to describe a limit process for the costs $C_n(x)$ as $x$ varies in $[0,1]$; one of the consequences is that $E{\\max_{x\\in [0,1]} C_n(x)} \\sim \\gamma n^\\beta$.
Unstructured Randomness, Small Gaps and Localization
Farhi, Edward; Gosset, David; Gutmann, Sam; Shor, Peter
2010-01-01
We study the Hamiltonian associated with the quantum adiabatic algorithm with a random cost function. Because the cost function lacks structure we can prove results about the ground state. We find the ground state energy as the number of bits goes to infinity, show that the minimum gap goes to zero exponentially quickly, and we see a localization transition. We prove that there are no levels approaching the ground state near the end of the evolution. We do not know which features of this model are shared by a quantum adiabatic algorithm applied to random instances of satisfiability since despite being random they do have bit structure.
Phase Transition in Computing Cost of Overconstrained NP-Complete 3-SAT Problems
Woodson, Adam; O'Donnell, Thomas; Maniloff, Peter
2002-03-01
Many intractable, NP-Complete problems such as Traveling Salesmen (TSP) and 3-Satisfiability (3-Sat) which arise in hundreds of computer science, industrial and commercial applications, are now known to exhibit phase transitions in computational cost. While these problems appear to not have any structure which would make them amenable to attack with quantum computing, their critical behavior may allow physical insights derived from statistical mechanics and critical theory to shed light on these computationally ``hardest" of problems. While computational theory indicates that ``the intractability of the NP-Complete class resides solely in the exponential growth of the possible solutions" with the number of variables, n, the present work instead investigates the complex patterns of ``overlap" amongst 3-SAT clauses (their combined effects) when n-tuples of these act in succession to reduce the space of valid solutions. An exhaustive-search algorithm was used to eliminate `bad' states from amongst the `good' states residing within the spaces of all 2^n--possible solutions of randomly generated 3-Sat problems. No backtracking nor optimization heuristics were employed, nor was problem structure exploited (i.e., phtypical cases were generated), and the (k=3)-Sat propositional logic problems generated were in standard, conjunctive normal form (CNF). Each problem had an effectively infinite number of clauses, m (i.e., with r = m/n >= 10), to insure every problem would not be satisfiable (i.e. that each would fail), and duplicate clauses were not permitted. This process was repeated for each of several low values of n (i.e., 4 animal populations.
Walsh, Terri; Warner, Lee; Macaluso, Maurizio; Frezieres, Ron; Snead, Margaret; Wraxall, Brian
2012-07-01
Prostate-specific antigen (PSA), a biomarker for semen exposure, may provide a more objective measure of condom failure than subject self-reports. Methods for measuring PSA vary and their comparability with respect to assessing condom performance has not been adequately evaluated. This study compared results from three different PSA assays of vaginal samples collected by subjects in a randomized clinical trial which compared the performance of female condoms. We selected 30 pairs of pre- and post-coital vaginal samples from subjects who reported condom functionality problems or whose original PSA assay was positive. Samples were retested using three different PSA assays [quantitative enzyme-linked immunoassay (EIA), rocket immune-electrophoresis (RIE) and chromatographic immunoassay (CIA)]. We compared the proportion of condom uses where the post-coital PSA result indicated semen exposure for each of the three assays. Despite varying levels of sensitivity, the results from all three assays were remarkably consistent. Self-reported condom failures did not correlate well with positive PSA results, suggesting that exclusive reliance on either PSA or user self-report may be inadequate for assessing condom functionality. In combination with user self-report of condom failure, PSA testing provides a reliable, objective marker of condom functionality. Studies based on PSA testing may improve on conventional contraceptive clinical trials by offering a more direct assessment of a condom product's ability to prevent semen exposure. Copyright © 2012 Elsevier Inc. All rights reserved.
Walsh, Terri; Warner, Lee; Macaluso, Maurizio; Frezieres, Ron; Snead, Margaret; Wraxall, Brian
2015-01-01
Background Prostate-specific antigen (PSA), a biomarker for semen exposure, may provide a more objective measure of condom failure than subject self-reports. Methods for measuring PSA vary and their comparability with respect to assessing condom performance has not been adequately evaluated. This study compared results from three different PSA assays of vaginal samples collected by subjects in a randomized clinical trial which compared the performance of female condoms. Study Design We selected 30 pairs of pre- and post-coital vaginal samples from subjects who reported condom functionality problems or whose original PSA assay was positive. Samples were retested using three different PSA assays [quantitative enzyme-linked immunoassay (EIA), rocket immune-electrophoresis (RIE) and chromatographic immunoassay (CIA)]. We compared the proportion of condom uses where the post-coital PSA result indicated semen exposure for each of the three assays. Results Despite varying levels of sensitivity, the results from all three assays were remarkably consistent. Self-reported condom failures did not correlate well with positive PSA results, suggesting that exclusive reliance on either PSA or user self-report may be inadequate for assessing condom functionality. Conclusion In combination with user self-report of condom failure, PSA testing provides a reliable, objective marker of condom functionality. Studies based on PSA testing may improve on conventional contraceptive clinical trials by offering a more direct assessment of a condom product's ability to prevent semen exposure. PMID:22386229
2010-04-01
... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false What documents satisfy the requirement that...? 1002.123 Section 1002.123 Employees' Benefits OFFICE OF THE ASSISTANT SECRETARY FOR VETERANS... documents showing periods of service; (7) Letter from National Disaster Medical System (NDMS) Team Leader...
A QoS-Satisfied Prediction Model for Cloud-Service Composition Based on a Hidden Markov Model
Qingtao Wu
2013-01-01
Full Text Available Various significant issues in cloud computing, such as service provision, service matching, and service assessment, have attracted researchers’ attention recently. Quality of service (QoS plays an increasingly important role in the provision of cloud-based services, by aiming for the seamless and dynamic integration of cloud-service components. In this paper, we focus on QoS-satisfied predictions about the composition of cloud-service components and present a QoS-satisfied prediction model based on a hidden Markov model. In providing a cloud-based service for a user, if the user’s QoS cannot be satisfied by a single cloud-service component, component composition should be considered, where its QoS-satisfied capability needs to be proactively predicted to be able to guarantee the user’s QoS. We discuss the proposed model in detail and prove some aspects of the model. Simulation results show that our model can achieve high prediction accuracies.
Nakagawa, Toshio
2014-01-01
Exploring random maintenance models, this book provides an introduction to the implementation of random maintenance, and it is one of the first books to be written on this subject. It aims to help readers learn new techniques for applying random policies to actual reliability models, and it provides new theoretical analyses of various models including classical replacement, preventive maintenance and inspection policies. These policies are applied to scheduling problems, backup policies of database systems, maintenance policies of cumulative damage models, and reliability of random redundant systems. Reliability theory is a major concern for engineers and managers, and in light of Japan’s recent earthquake, the reliability of large-scale systems has increased in importance. This also highlights the need for a new notion of maintenance and reliability theory, and how this can practically be applied to systems. Providing an essential guide for engineers and managers specializing in reliability maintenance a...
Scott, A; Smith, R D
1994-12-01
Patient satisfaction and customer focus are increasingly important objectives set for health services. The patient satisfaction survey is becoming the main method of assessing this aspect of health care. In competitive environments, those institutions that show that they respond to consumers' needs are in a better position to attract funding. The use of patient satisfaction surveys in quality assurance-type activities is also increasing. In these contexts, however, the way in which patient satisfaction surveys should be interpreted and used to maximise the satisfaction of patients has received little critical attention. Problems in interpreting the results of satisfaction surveys arise from the weak conceptual foundation of patient satisfaction, which has been well documented in the literature. The objective of this paper is to show that using current formulations of patient satisfaction surveys in quality assurance-type activities and competitive environments may not lead to the maximisation of patients' satisfaction with health services. If the satisfaction of patients is to be maximised then it is necessary to extend the current conceptual basis of patient satisfaction to recognise explicitly the decision-making contexts in which the results will be used. This paper identifies the manner by which this extension should occur by considering some of the problems and pitfalls of interpreting and using the results of surveys to maximise patients' satisfaction.
Korhonen, Joonas; Adams, Clive E; Koivunen, Marita Hannele; Vahlberg, Tero; Välimäki, Maritta Anneli
2017-01-01
Background Clinical trials are the gold standard of evidence-based practice. Still many papers inadequately report methodology in randomized controlled trials (RCTs), particularly for mHealth interventions for people with serious mental health problems. To ensure robust enough evidence, it is important to understand which study phases are the most vulnerable in the field of mental health care. Objective We mapped the recruitment and the trial follow-up periods of participants to provide a picture of the dropout predictors from a mHealth-based trial. As an example, we used a mHealth-based multicenter RCT, titled “Mobile.Net,” targeted at people with serious mental health problems. Methods Recruitment and follow-up processes of the Mobile.Net trial were monitored and analyzed. Recruitment outcomes were recorded as screened, eligible, consent not asked, refused, and enrolled. Patient engagement was recorded as follow-up outcomes: (1) attrition during short message service (SMS) text message intervention and (2) attrition during the 12-month follow-up period. Multiple regression analysis was used to identify which demographic factors were related to recruitment and retention. Results We recruited 1139 patients during a 15-month period. Of 11,530 people screened, 36.31% (n=4186) were eligible. This eligible group tended to be significantly younger (mean 39.2, SD 13.2 years, P<.001) and more often women (2103/4181, 50.30%) than those who were not eligible (age: mean 43.7, SD 14.6 years; women: 3633/6514, 55.78%). At the point when potential participants were asked to give consent, a further 2278 refused. Those who refused were a little older (mean 40.2, SD 13.9 years) than those who agreed to participate (mean 38.3, SD 12.5 years; t1842=3.2, P<.001). We measured the outcomes after 12 months of the SMS text message intervention. Attrition from the SMS text message intervention was 4.8% (27/563). The patient dropout rate after 12 months was 0.36% (4/1123), as
Han, Win T; Collie, Kate; Koopman, Cheryl; Azarow, Jay; Classen, Catherine; Morrow, Gary R; Michel, Betsy; Brennan-O'Neill, Eileen; Spiegel, David
2005-04-01
This investigation examined relationships between breast cancer patients' psychosocial characteristics (impact of the illness, traumatic stress symptoms, emotional self-efficacy, and social support) and problems they perceived in their medical interactions and their satisfaction with their physicians. Participants were 352 women enrolled in a multicenter trial of the effects of group therapy for women with recently diagnosed primary breast cancer. The findings reported here are from a cross-sectional analysis of baseline data gathered prior to randomization. Problems interacting with physicians and nurses were associated with greater levels of cancer-related traumatic stress (p < 0.01), less emotional self-efficacy for cancer (p < 0.05), less satisfaction with informational support from family, friends, and spouse, and a tendency to perceive those sources of support as more aversive (p < 0.05). Women who were less satisfied with emotional support from their family, friends and spouse were less likely to feel satisfied with their physicians (p < 0.05). These patient characteristics identify women with primary breast cancer who are likely to experience difficulty in their interactions with nurses and physicians and to be less satisfied with their physicians.
An Improved Distribution Policy with a Maintenance Aspect for an Urban Logistic Problem
Nadia Ndhaief
2017-07-01
Full Text Available In this paper, we present an improved distribution plan supporting an urban distribution center (UDC to solve the last mile problem of urban freight. This is motivated by the need of UDCs to satisfy daily demand in time under a high service level in allocated urban areas. Moreover, these demands could not be satisfied in individual cases because the delivery rate can be less than daily demand and/or affected by random failure or maintenance actions of vehicles. The scope of our work is to focus on a UDC, which needs to satisfy demands in a finite horizon. To that end, we consider a distribution policy on two sequential plans, a distribution plan correlated to a maintenance plan using a subcontracting strategy with several potential urban distribution centers (UDCs and performing preventive maintenance to ensure deliveries for their allocated urban area. The choice of subcontractor will depend on distance, environmental and availability criteria. In doing so, we define a mathematical model for searching the best distribution and maintenance plans using a subcontracting strategy. Moreover, we consider delay for the next periods with an expensive penalty. Finally, we present a numerical example illustrating the benefits of our approach.
Hashing, Randomness and Dictionaries
Pagh, Rasmus
time and memory space. To some extent we also consider lower bounds, i.e., we attempt to show limitations on how efficient algorithms are possible. A central theme in the thesis is randomness. Randomized algorithms play an important role, in particular through the key technique of hashing. Additionally...... algorithms community. We work (almost) exclusively with a model, a mathematical object that is meant to capture essential aspects of a real computer. The main model considered here (and in most of the literature on dictionaries) is a unit cost RAM with a word size that allows a set element to be stored...... in one word. We consider several variants of the dictionary problem, as well as some related problems. The problems are studied mainly from an upper bound perspective, i.e., we try to come up with algorithms that are as efficient as possible with respect to various computing resources, mainly computation...
Quantum random number generator using photon-number path entanglement
Kwon, Osung; Cho, Young-Wook; Kim, Yoon-Ho
2010-08-01
We report an experimental implementation of quantum random number generator based on the photon-number-path entangled state. The photon-number-path entangled state is prepared by means of two-photon Hong-Ou-Mandel quantum interference at a beam splitter. The randomness in our scheme is of truly quantum mechanical origin as it comes from the projection measurement of the entangled two-photon state. The generated bit sequences satisfy the standard randomness test.
Multiobjective Economic Load Dispatch Problem Solved by New PSO
Nagendra Singh
2015-01-01
Full Text Available Proposed in this paper is a new particle swarm optimization technique for the solution of economic load dispatch as well as environmental emission of the thermal power plant with power balance and generation limit constraints. Economic load dispatch is an online problem to minimize the total generating cost of the thermal power plant and satisfy the equality and inequality constraints. Thermal power plants use fossil fuels for the generation of power; fossil fuel emits many toxic gases which pollute the environment. This paper not only considers the economic load dispatch problem to reduce the total generation cost of the thermal power plant but also deals with environmental emission minimization. In this paper, fuel cost and the environmental emission functions are considered and formulated as a multiobjective economic load dispatch problem. For obtaining the solution of multiobjective economic load dispatch problem a new PSO called moderate random search PSO was used. MRPSO enhances the ability of particles to explore in the search spaces more effectively and increases their convergence rates. The proposed algorithm is tested for the IEEE 30 bus test systems. The results obtained by MRPSO algorithm show that it is effective and efficient.
Applying inversion to construct planar, rational spirals that satisfy two-point G(2) Hermite data
Kurnosenko, A
2010-01-01
A method of two-point G(2) Hermite interpolation with spirals is proposed. To construct a sought for curve, the inversion is applied to an arc of some other spiral. To illustrate the method, inversions of parabola are considered in detail. The resulting curve is 4th degree rational. The method allows the matching of a wide range of boundary conditions, including those which require an inflection. Although not all G(2) Hermite data can be matched with a spiral generated from a parabolic arc, introducing one intermediate G(2) data solves the problem. Expanding the method by involving other spirals arcs is also discussed. (C) 2009 Elsevier B.V. All rights reserved.
Catalin Lupu
2007-01-01
Full Text Available Electronic Business, or “E-business”, maybe defined broadly as any business process that relies onan automated information system. Today, this is mostlydone with Web-based technologies. In practice, ebusinessis more than just e-commerce. E-businessinvolves business processes spanning the entire valuechain: electronic purchasing and supply chainmanagement, processing orders electronically, handlingcustomer service, and cooperating with businesspartners. The GIS exist all over the world and this solvesdifferent problems. In business administration - the GIStechnology develops in the traditional GIS communityand thus becomes a component integrated in theinformational infrastructure of many organizations. GISassures essential informational instruments for differentclasses of informational systems. As IT users, you mayhave the possibility to use the best instruments for: to coordinateand communicate the main concepts betweenthe departments of an organization; to pass importantinformation inside the organization; to administrate andto keep an infrastructure that focuses on spatial data.
Ising formulations of many NP problems
Lucas, Andrew
2014-02-01
We provide Ising formulations for many NP-complete and NP-hard problems, including all of Karp's 21 NP-complete problems. This collects and extends mappings to the Ising model from partitioning, covering and satisfiability. In each case, the required number of spins is at most cubic in the size of the problem. This work may be useful in designing adiabatic quantum optimization algorithms.
The exact packing measure for a random re-ordering of the Cantor set
胡晓予
1996-01-01
The packing measure for a random re-ordering of the Cantor set, the packing dimension for the random set belonging to a sequence satisfying the Hausdorff and packing measures and packing measures for random subsets of R belonging to a regular sequence have been obtained.
A self-similar process arising from a random walk with random environment in random scenery
Franke, Brice; 10.3150/09-BEJ234
2011-01-01
In this article, we merge celebrated results of Kesten and Spitzer [Z. Wahrsch. Verw. Gebiete 50 (1979) 5-25] and Kawazu and Kesten [J. Stat. Phys. 37 (1984) 561-575]. A random walk performs a motion in an i.i.d. environment and observes an i.i.d. scenery along its path. We assume that the scenery is in the domain of attraction of a stable distribution and prove that the resulting observations satisfy a limit theorem. The resulting limit process is a self-similar stochastic process with non-trivial dependencies.
Campbell, William; Hester, Reid K; Lenberg, Kathryn L; Delaney, Harold D
2016-10-04
Despite empirical evidence supporting the use of Web-based interventions for problem drinking, much remains unknown about factors that influence their effectiveness. We evaluated the performance of 2 resources for people who want to achieve and maintain abstinence: SMART Recovery (SR) and Overcoming Addictions (OA). OA is a Web application based on SR. We also examined participant and intervention-related factors hypothesized to impact clinical outcomes of Web-based interventions. We recruited 189 heavy drinkers through SR's website and in-person meetings throughout the United States. We began by randomly assigning participants to (1) SR meetings alone, (2) OA alone, and (3) OA and SR (OA+SR). Recruitment challenges compelled us to assign participants only to SR (n=86) or OA+SR (n=102). The experimental hypotheses were as follows: (1) Both groups will reduce their drinking and alcohol-related consequences at follow-up compared with their baseline levels, and (2) The OA+SR condition will reduce their drinking and alcohol or drug-related consequences more than the SR only condition. Additionally, we derived 3 groups empirically (SR, OA, and OA+SR) based on the participants' actual use of each intervention and conducted analyses by comparing them. Primary outcome measures included percent days abstinent (PDA), mean drinks per drinking day (DDD), and alcohol or drug-related consequences. Postbaseline assessments were conducted by phone at 3 and 6 months. Secondary analyses explored whether clinical issues (eg, severity of alcohol problems, level of distress, readiness to change) or intervention-related factors (eg, Internet fluency, satisfaction with site) affected outcomes. Both intent-to-treat analyses and the actual-use analyses showed highly significant improvement from baseline to follow-ups for all 3 groups. Mean within-subject effect sizes were large (d>0.8) overall. There was no significant difference between groups in the amount of improvement from baseline to
Hester, Reid K; Lenberg, Kathryn L; Delaney, Harold D
2016-01-01
Background Despite empirical evidence supporting the use of Web-based interventions for problem drinking, much remains unknown about factors that influence their effectiveness. Objective We evaluated the performance of 2 resources for people who want to achieve and maintain abstinence: SMART Recovery (SR) and Overcoming Addictions (OA). OA is a Web application based on SR. We also examined participant and intervention-related factors hypothesized to impact clinical outcomes of Web-based interventions. Methods We recruited 189 heavy drinkers through SR’s website and in-person meetings throughout the United States. We began by randomly assigning participants to (1) SR meetings alone, (2) OA alone, and (3) OA and SR (OA+SR). Recruitment challenges compelled us to assign participants only to SR (n=86) or OA+SR (n=102). The experimental hypotheses were as follows: (1) Both groups will reduce their drinking and alcohol-related consequences at follow-up compared with their baseline levels, and (2) The OA+SR condition will reduce their drinking and alcohol or drug-related consequences more than the SR only condition. Additionally, we derived 3 groups empirically (SR, OA, and OA+SR) based on the participants’ actual use of each intervention and conducted analyses by comparing them. Primary outcome measures included percent days abstinent (PDA), mean drinks per drinking day (DDD), and alcohol or drug-related consequences. Postbaseline assessments were conducted by phone at 3 and 6 months. Secondary analyses explored whether clinical issues (eg, severity of alcohol problems, level of distress, readiness to change) or intervention-related factors (eg, Internet fluency, satisfaction with site) affected outcomes. Results Both intent-to-treat analyses and the actual-use analyses showed highly significant improvement from baseline to follow-ups for all 3 groups. Mean within-subject effect sizes were large (d>0.8) overall. There was no significant difference between groups in
Conditional variable importance for random forests
Strobl, Carolin; Boulesteix, Anne-Laure; Kneib, Thomas; Augustin, Thomas; Zeileis, Achim
2008-01-01
Random forests are becoming increasingly popular in many scientific fields because they can cope with "small n large p" problems, complex interactions and even highly correlated predictor variables...
Andrej Pinter
2004-01-01
Full Text Available This paper deals with a specific segment of libraries’ activities which has been much exposed recently – the user. For the library of today, opinions of its users are no longer a curiosity; they are an important aspect of its research activities and also of its administrative practices. The purpose of this paper is thus twofold: to outline a broader framework of library users research and to discuss selected dilemmas that commonly arise in this framework. As users research has become a prominent activity in the international arena and has also established itself in Slovenia, the paper comments on most popular measurement instruments for library users research (SERVQUAL, LibQUAL+ and also on the ways of defining key dimensions of users’ perceptions of the library service. Special attention is placed on a systematic distinction between the concept of library service quality and users’ satisfaction. This is an important conceptual dilemma which also affects research methodology. The concluding part of the paper presents and empirical analysis of the relation between the selected dimensions of users’ satisfaction and their success in searching for desired library materials. This problem is conceptually extracted from contemporary debates about the results of users’ research, whereas in practical terms it derives from the context of one of the public libraries in Ljubljana.
Leenen, L
2007-12-01
Full Text Available The authors present a variant of the Weighted Maximum Satisfiability Problem (Weighted Max-SAT), which is a modeling of the Semiring Constraint Satisfaction framework. They show how to encode a Semiring Constraint Satisfaction Problem (SCSP...
ajansen; kwhitefoot; panteltje1; edprochak; sudhakar, the
2014-07-01
In reply to the physicsworld.com news story “How to make a quantum random-number generator from a mobile phone” (16 May, http://ow.ly/xFiYc, see also p5), which describes a way of delivering random numbers by counting the number of photons that impinge on each of the individual pixels in the camera of a Nokia N9 smartphone.
Sumit Chandok
2013-03-01
Full Text Available The purpose of this paper is to establish some coupled coincidence point theorems for a pair of mappings having a mixed $g$-monotone property satisfying a contractive condition of rational type in the framework of partially ordered metric spaces. Also, we present a result on the existence and uniqueness of coupled common fixed points. The results presented in the paper generalize and extend several well-known results in the literature.
WU Hao; FAN Hong-Yi
2008-01-01
Eigenvalue-solution to those Hamiltonians involving non-commutative coordinates is not easily obtained. In this paper we apply the invariant eigen-operator (IEO) method to solving the energy spectrum of the three-mode harmonic oscillator in non-commutative space with the coordinate operators satisfying cyclic commutative relations, [X1, X2]=[X2, X3]=[X3, X1]=iθ, and this method seems effective and concise.
Orthogonal polynomials and random matrices
Deift, Percy
2000-01-01
This volume expands on a set of lectures held at the Courant Institute on Riemann-Hilbert problems, orthogonal polynomials, and random matrix theory. The goal of the course was to prove universality for a variety of statistical quantities arising in the theory of random matrix models. The central question was the following: Why do very general ensembles of random n {\\times} n matrices exhibit universal behavior as n {\\rightarrow} {\\infty}? The main ingredient in the proof is the steepest descent method for oscillatory Riemann-Hilbert problems.
Telyakovskii, D. S.
2017-01-01
In this paper we weaken the sufficient conditions of harmonicity for functions of two variables. I.I. Privalov had shown that a continuous function that satisfies the Laplace equation in each point of the domain is harmonic. For function of two variables the Privalov’s condition on continuity can be weakened. G.P. Tolstov replaced the continuity condition by the boundness condition, later the author had shown that summability is sufficient. At the same time summability condition can not be weakened substantially. In this paper, while we keep the summability condition, we provide the sufficient condition for harmonicity of the functions, that satisfy less restricted condition than the Laplace equation in all points of the domain. We assume that arbitrary close to any point ζ there exists a collection of four nodes for which a difference relation of Schwartz type for the Laplace equation can be made arbitrary small by the absolute value. Nodes are the ends of two mutually perpendicular segments, that intersect at point ζ. We need to impose a certain weakened continuous assumption on function itself, in case of function that satisfy the traditional Laplace condition this continuity condition follows from the existence of the partial derivatives.
Scale-Invariant Random Spatial Networks
Aldous, David J
2012-01-01
Real-world road networks have an approximate scale-invariance property; can one devise mathematical models of random networks whose distributions are {\\em exactly} invariant under Euclidean scaling? This requires working in the continuum plane. We introduce an axiomatization of a class of processes we call {\\em scale-invariant random spatial networks}, whose primitives are routes between each pair of points in the plane. We prove that one concrete model, based on minimum-time routes in a binary hierarchy of roads with different speed limits, satisfies the axioms, and note informally that two other constructions (based on Poisson line processes and on dynamic proximity graphs) are expected also to satisfy the axioms. We initiate study of structure theory and summary statistics for general processes in this class.
Analysis of Additive Random Number Generators.
1977-03-01
linear congruential generators yn*\\* ayn+bmo,iPa- The simplest example of a sequence satisfying (1.1) with *> I is the Fibonacci sequence with p - 2...However, the Fibonacci sequence is not a suitable random number generator because successive triples are very poorly distributed in three...number generator should have small discrepancy. Definition 2.1 can be extended naturally to define discrepancy for sequences of points yn lying in
Obstacle mean-field game problem
Gomes, Diogo A.
2015-01-01
In this paper, we introduce and study a first-order mean-field game obstacle problem. We examine the case of local dependence on the measure under assumptions that include both the logarithmic case and power-like nonlinearities. Since the obstacle operator is not differentiable, the equations for first-order mean field game problems have to be discussed carefully. Hence, we begin by considering a penalized problem. We prove this problem admits a unique solution satisfying uniform bounds. These bounds serve to pass to the limit in the penalized problem and to characterize the limiting equations. Finally, we prove uniqueness of solutions. © European Mathematical Society 2015.
Neutron transport in random media
Makai, M. [KFKI Atomic Energy Research Institute, Budapest (Hungary)
1996-08-01
The survey reviews the methods available in the literature which allow a discussion of corium recriticality after a severe accident and a characterization of the corium. It appears that to date no one has considered the eigenvalue problem, though for the source problem several approaches have been proposed. The mathematical formulation of a random medium may be approached in different ways. Based on the review of the literature, we can draw three basic conclusions. The problem of static, random perturbations has been solved. The static case is tractable by the Monte Carlo method. There is a specific time dependent case for which the average flux is given as a series expansion.
... you are having balance problems, see your doctor. Balance disorders can be signs of other health problems, such ... cases, treating the illness that is causing the disorder will help with the balance problem. Exercises, a change in diet, and some ...
Phase transitions in number theory: from the birthday problem to Sidon sets.
Luque, Bartolo; Torre, Iván G; Lacasa, Lucas
2013-11-01
In this work, we show how number theoretical problems can be fruitfully approached with the tools of statistical physics. We focus on g-Sidon sets, which describe sequences of integers whose pairwise sums are different, and propose a random decision problem which addresses the probability of a random set of k integers to be g-Sidon. First, we provide numerical evidence showing that there is a crossover between satisfiable and unsatisfiable phases which converts to an abrupt phase transition in a properly defined thermodynamic limit. Initially assuming independence, we then develop a mean-field theory for the g-Sidon decision problem. We further improve the mean-field theory, which is only qualitatively correct, by incorporating deviations from independence, yielding results in good quantitative agreement with the numerics for both finite systems and in the thermodynamic limit. Connections between the generalized birthday problem in probability theory, the number theory of Sidon sets and the properties of q-Potts models in condensed matter physics are briefly discussed.
Rosenblum, Michael; Liu, Han; Yen, En-Hsu
2014-01-01
We propose new, optimal methods for analyzing randomized trials, when it is suspected that treatment effects may differ in two predefined subpopulations. Such subpopulations could be defined by a biomarker or risk factor measured at baseline. The goal is to simultaneously learn which subpopulations benefit from an experimental treatment, while providing strong control of the familywise Type I error rate. We formalize this as a multiple testing problem and show it is computationally infeasible to solve using existing techniques. Our solution involves a novel approach, in which we first transform the original multiple testing problem into a large, sparse linear program. We then solve this problem using advanced optimization techniques. This general method can solve a variety of multiple testing problems and decision theory problems related to optimal trial design, for which no solution was previously available. In particular, we construct new multiple testing procedures that satisfy minimax and Bayes optimality criteria. For a given optimality criterion, our new approach yields the optimal tradeoff between power to detect an effect in the overall population versus power to detect effects in subpopulations. We demonstrate our approach in examples motivated by two randomized trials of new treatments for HIV.
Muhammad Aslam Noor
2004-01-01
Full Text Available We consider a new class of equilibrium problems, known as hemiequilibrium problems. Using the auxiliary principle technique, we suggest and analyze a class of iterative algorithms for solving hemiequilibrium problems, the convergence of which requires either pseudomonotonicity or partially relaxed strong monotonicity. As a special case, we obtain a new method for hemivariational inequalities. Since hemiequilibrium problems include hemivariational inequalities and equilibrium problems as special cases, the results proved in this paper still hold for these problems.
Mehta, Madan Lal
1990-01-01
Since the publication of Random Matrices (Academic Press, 1967) so many new results have emerged both in theory and in applications, that this edition is almost completely revised to reflect the developments. For example, the theory of matrices with quaternion elements was developed to compute certain multiple integrals, and the inverse scattering theory was used to derive asymptotic results. The discovery of Selberg's 1944 paper on a multiple integral also gave rise to hundreds of recent publications. This book presents a coherent and detailed analytical treatment of random matrices, leading
An algorithm for 3-SAT problems
Tsukimoto, Hiroshi
2016-01-01
This paper presents an algorithm for 3-SAT problems. First, logical formulas are transformed into elementary algebraic formulas. Second, complex trigonometric functions are assigned to the variables in the elementary algebraic formulas, and the sums of the formulas are calculated. The algorithm outputs the number of satisfying assignments. The computational complexity of the algorithm is probably polynomial.
Inherent randomicity in 4-symbolic dynamics
Zhang Yagang [Department of Applied Mathematics, School of Mathematics and Physics, North China Electric Power University, Box 235, Baoding, Hebei 071003 (China); Center for Nonlinear Complex Systems, Department of Physics, Yunnan University, Kunming, Yunnan 650091 (China); E-mail: ygzhg@163.com; Wang Changjiang [Department of Physics, Yunnan University, Kunming, Yunnan 650091 (China); Zhou Zhong [Center for Nonlinear Complex Systems, Department of Physics, Yunnan University, Kunming, Yunnan 650091 (China)
2006-04-01
The inherent randomicity in 4-symbolic dynamics will be clarified in this paper. The symbolic sequences bear three characteristics. The distribution of frequency, inter-occurrence times and the alignment of two random sequences are amplified in detail. By using transfer probability of Markov chain (MC), we obtain analytic expressions of generating functions in four probabilities stochastic wander model, which can be applied to all 4-symbolic systems. We hope to offer a symbolic platform that satisfies these stochastic properties and to study some properties of DNA sequences.
New SAT solver based on finding satisfiable 2-SAT sub problem%基于寻找可满足2-SAT子问题的SAT算法
傅阳春; 周育人
2010-01-01
可满足问题(SAT)是一个NP-Hard问题.提出了一种求解SAT的新算法(FFSAT).该算法将SAT问题转换为寻找一个可满足的2-SAT子问题.SAT问题虽然是NP完全问题,但是当所有子句长度不大于2时,SAT问题可以在线性时间求解.使用2-SAT算法-BinSat求解2-SAT子问题,当它不满足时,根据赋值选择新的2-SAT子问题.实验结果表明,采用本算法的结果优于UnitWalk.
Variational Infinite Hidden Conditional Random Fields
Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja; Ghahramani, Zoubin
2015-01-01
Hidden conditional random fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An Infinite hidden conditional random field is a hidden conditional random field with a countably infinite number of
Strong jump traceability and Demuth randomness
Greenberg, Noam
2011-01-01
We solve the covering problem for Demuth randomness, showing that a computably enumerable set is computable from a Demuth random set if and only if it is strongly jump-traceable. We show that on the other hand, the class of sets which form a base for Demuth randomness is a proper subclass of the class of strongly jump-traceable sets.
Moschandreas, D. J.; Vuilleumier, K. L.
Prior to this study, indoor air constituent levels and ventilation rates of hospitality environments had not been measured simultaneously. This investigation measured indoor Environmental Tobacco Smoke-related (ETS-related) constituent levels in two restaurants, a billiard hall and a casino. The objective of this study was to characterize ETS-related constituent levels inside hospitality environments when the ventilation rates satisfy the requirements of the ASHRAE 62-1989 Ventilation Standard. The ventilation rate of each selected hospitality environment was measured and adjusted. The study advanced only if the requirements of the ASHRAE 62-1989 Ventilation Standard - the pertinent standard of the American Society of Heating, Refrigeration and Air Conditioning Engineers - were satisfied. The supply rates of outdoor air and occupant density were measured intermittently to assure that the ventilation rate of each facility satisfied the standard under occupied conditions. Six ETS-related constituents were measured: respirable suspended particulate (RSP) matter, fluorescent particulate matter (FPM, an estimate of the ETS particle concentrations), ultraviolet particulate matter (UVPM, a second estimate of the ETS particle concentrations), solanesol, nicotine and 3-ethenylpyridine (3-EP). ETS-related constituent levels in smoking sections, non-smoking sections and outdoors were sampled daily for eight consecutive days at each hospitality environment. This study found that the difference between the concentrations of ETS-related constituents in indoor smoking and non-smoking sections was statistically significant. Differences between indoor non-smoking sections and outdoor ETS-related constituent levels were identified but were not statistically significant. Similarly, differences between weekday and weekend evenings were identified but were not statistically significant. The difference between indoor smoking sections and outdoors was statistically significant. Most
Counting problems for number rings
Brakenhoff, Johannes Franciscus
2009-01-01
In this thesis we look at three counting problems connected to orders in number fields. First we study the probability that for a random polynomial f in Z[X] the ring Z[X]/f is the maximal order in Q[X]/f. Connected to this is the probability that a random polynomial has a squarefree discriminant. T
Derrida, B.; Mecheri, K.; Pichard, J.L.
1987-05-01
We derive the weak disorder expansion of the Lyapounov exponents of a product of random matrices. The condition for this expansion to be valid is that in the limit of zero disorder, the matrix has all its eigenvalues with different moduli. As an example, we study the problem of localisation on strips in the limit of weak disorder. We show that our expansion agrees very well with numerical simulations in the region where the condition on the moduli is satisfied which corresponds to energies outside the conduction band. In that region, we find a limiting density of Lyapounov exponents when the strip width goes to infinity. Inside the band, our expansion cannot be valid unless one adds an imaginary part to the energy.
Palm theory for random time changes
Masakiyo Miyazawa
2001-01-01
Full Text Available Palm distributions are basic tools when studying stationarity in the context of point processes, queueing systems, fluid queues or random measures. The framework varies with the random phenomenon of interest, but usually a one-dimensional group of measure-preserving shifts is the starting point. In the present paper, by alternatively using a framework involving random time changes (RTCs and a two-dimensional family of shifts, we are able to characterize all of the above systems in a single framework. Moreover, this leads to what we call the detailed Palm distribution (DPD which is stationary with respect to a certain group of shifts. The DPD has a very natural interpretation as the distribution seen at a randomly chosen position on the extended graph of the RTC, and satisfies a general duality criterion: the DPD of the DPD gives the underlying probability P in return.
Suzanne; Rostler; 尤北还
2001-01-01
作为上篇的一个姊妹篇,我们很乐意向读者推荐本文。古人云,知足常乐。读完本文,也许你会改其二字:知足长寿。文章告诉我们: Men who reported high levels of satisfaction with their lives were more likely to be alive 20 years later. 知足者竟然能在这个世界上多生活20年!你信否? 文章还提到了男女之别,颇发人深省: It seems to me that the coping abilities of women with distress and dissatisfaction may be better than in men. Men who feel dissatisfied might cope with their feelings by abusing alcohol, smoking and not exercising while women might talk to friends or seek professional help. 你若是男性读者,是否可以从中得到某种启迪? 文章最精彩的句子大概在文末: It is not enough for a human being to earn money and be in physically good condition. One should respect mental health as well.】
Keeping Your Customers Satisfied.
Maurer, Mary E.
1996-01-01
Notes that because child care is a customer-service business with many of the same requirements as any retail business, it is important that providers communicate clearly, help their customers (especially parents), and understand their needs. Offers suggestions for meeting parents' needs and making them feel like active participants in their…
Dubina, Sean Hyun; Wedgewood, Lewis Edward
2016-07-01
Ferrofluids are often favored for their ability to be remotely positioned via external magnetic fields. The behavior of particles in ferromagnetic clusters under uniformly applied magnetic fields has been computationally simulated using the Brownian dynamics, Stokesian dynamics, and Monte Carlo methods. However, few methods have been established that effectively handle the basic principles of magnetic materials, namely, Maxwell's equations. An iterative constraint method was developed to satisfy Maxwell's equations when a uniform magnetic field is imposed on ferrofluids in a heterogeneous Brownian dynamics simulation that examines the impact of ferromagnetic clusters in a mesoscale particle collection. This was accomplished by allowing a particulate system in a simple shear flow to advance by a time step under a uniformly applied magnetic field, then adjusting the ferroparticles via an iterative constraint method applied over sub-volume length scales until Maxwell's equations were satisfied. The resultant ferrofluid model with constraints demonstrates that the magnetoviscosity contribution is not as substantial when compared to homogeneous simulations that assume the material's magnetism is a direct response to the external magnetic field. This was detected across varying intensities of particle-particle interaction, Brownian motion, and shear flow. Ferroparticle aggregation was still extensively present but less so than typically observed.
Dubina, Sean Hyun, E-mail: sdubin2@uic.edu; Wedgewood, Lewis Edward, E-mail: wedge@uic.edu [Department of Chemical Engineering, University of Illinois at Chicago, 810 S. Clinton St. (MC 110), Chicago, Illinois 60607-4408 (United States)
2016-07-15
Ferrofluids are often favored for their ability to be remotely positioned via external magnetic fields. The behavior of particles in ferromagnetic clusters under uniformly applied magnetic fields has been computationally simulated using the Brownian dynamics, Stokesian dynamics, and Monte Carlo methods. However, few methods have been established that effectively handle the basic principles of magnetic materials, namely, Maxwell’s equations. An iterative constraint method was developed to satisfy Maxwell’s equations when a uniform magnetic field is imposed on ferrofluids in a heterogeneous Brownian dynamics simulation that examines the impact of ferromagnetic clusters in a mesoscale particle collection. This was accomplished by allowing a particulate system in a simple shear flow to advance by a time step under a uniformly applied magnetic field, then adjusting the ferroparticles via an iterative constraint method applied over sub-volume length scales until Maxwell’s equations were satisfied. The resultant ferrofluid model with constraints demonstrates that the magnetoviscosity contribution is not as substantial when compared to homogeneous simulations that assume the material’s magnetism is a direct response to the external magnetic field. This was detected across varying intensities of particle-particle interaction, Brownian motion, and shear flow. Ferroparticle aggregation was still extensively present but less so than typically observed.
Vempala, Santosh S
2005-01-01
Random projection is a simple geometric technique for reducing the dimensionality of a set of points in Euclidean space while preserving pairwise distances approximately. The technique plays a key role in several breakthrough developments in the field of algorithms. In other cases, it provides elegant alternative proofs. The book begins with an elementary description of the technique and its basic properties. Then it develops the method in the context of applications, which are divided into three groups. The first group consists of combinatorial optimization problems such as maxcut, graph coloring, minimum multicut, graph bandwidth and VLSI layout. Presented in this context is the theory of Euclidean embeddings of graphs. The next group is machine learning problems, specifically, learning intersections of halfspaces and learning large margin hypotheses. The projection method is further refined for the latter application. The last set consists of problems inspired by information retrieval, namely, nearest neig...
Pseudo-Hermitian ensemble of random Gaussian matrices.
Marinello, G; Pato, M P
2016-07-01
It is shown how pseudo-Hermiticity, a necessary condition satisfied by operators of PT symmetric systems can be introduced in the three Gaussian classes of random matrix theory. The model describes transitions from real eigenvalues to a situation in which, apart from a residual number, the eigenvalues are complex conjugate.
Pseudo-Hermitian ensemble of random Gaussian matrices
Marinello, G.; Pato, M. P.
2016-07-01
It is shown how pseudo-Hermiticity, a necessary condition satisfied by operators of PT symmetric systems can be introduced in the three Gaussian classes of random matrix theory. The model describes transitions from real eigenvalues to a situation in which, apart from a residual number, the eigenvalues are complex conjugate.
On belief propagation guided decimation for random k-SAT
Coja-Oghlan, Amin
2010-01-01
Let F be a uniformly distributed random k-SAT formula with n variables and m clauses. Non-constructive arguments show that F is satisfiable for clause/variable ratios m/nc.r(k)/k, for a constant c>0 (independent of k).
Random Matrix theory approach to Quantum mechanics
Chaitanya, K. V. S. Shiv
2015-01-01
In this paper, we give random matrix theory approach to the quantum mechanics using the quantum Hamilton-Jacobi formalism. We show that the bound state problems in quantum mechanics are analogous to solving Gaussian unitary ensemble of random matrix theory. This study helps in identify the potential appear in the joint probability distribution function in the random matrix theory as a super potential. This approach allows to extend the random matrix theory to the newly discovered exceptional ...
A new approach for inversion of large random matrices in massive MIMO systems.
Muhammad Ali Raza Anjum
Full Text Available We report a novel approach for inversion of large random matrices in massive Multiple-Input Multiple Output (MIMO systems. It is based on the concept of inverse vectors in which an inverse vector is defined for each column of the principal matrix. Such an inverse vector has to satisfy two constraints. Firstly, it has to be in the null-space of all the remaining columns. We call it the null-space problem. Secondly, it has to form a projection of value equal to one in the direction of selected column. We term it as the normalization problem. The process essentially decomposes the inversion problem and distributes it over columns. Each column can be thought of as a node in the network or a particle in a swarm seeking its own solution, the inverse vector, which lightens the computational load on it. Another benefit of this approach is its applicability to all three cases pertaining to a linear system: the fully-determined, the over-determined, and the under-determined case. It eliminates the need of forming the generalized inverse for the last two cases by providing a new way to solve the least squares problem and the Moore and Penrose's pseudoinverse problem. The approach makes no assumption regarding the size, structure or sparsity of the matrix. This makes it fully applicable to much in vogue large random matrices arising in massive MIMO systems. Also, the null-space problem opens the door for a plethora of methods available in literature for null-space computation to enter the realm of matrix inversion. There is even a flexibility of finding an exact or approximate inverse depending on the null-space method employed. We employ the Householder's null-space method for exact solution and present a complete exposition of the new approach. A detailed comparison with well-established matrix inversion methods in literature is also given.
A new approach for inversion of large random matrices in massive MIMO systems.
Anjum, Muhammad Ali Raza; Ahmed, Muhammad Mansoor
2014-01-01
We report a novel approach for inversion of large random matrices in massive Multiple-Input Multiple Output (MIMO) systems. It is based on the concept of inverse vectors in which an inverse vector is defined for each column of the principal matrix. Such an inverse vector has to satisfy two constraints. Firstly, it has to be in the null-space of all the remaining columns. We call it the null-space problem. Secondly, it has to form a projection of value equal to one in the direction of selected column. We term it as the normalization problem. The process essentially decomposes the inversion problem and distributes it over columns. Each column can be thought of as a node in the network or a particle in a swarm seeking its own solution, the inverse vector, which lightens the computational load on it. Another benefit of this approach is its applicability to all three cases pertaining to a linear system: the fully-determined, the over-determined, and the under-determined case. It eliminates the need of forming the generalized inverse for the last two cases by providing a new way to solve the least squares problem and the Moore and Penrose's pseudoinverse problem. The approach makes no assumption regarding the size, structure or sparsity of the matrix. This makes it fully applicable to much in vogue large random matrices arising in massive MIMO systems. Also, the null-space problem opens the door for a plethora of methods available in literature for null-space computation to enter the realm of matrix inversion. There is even a flexibility of finding an exact or approximate inverse depending on the null-space method employed. We employ the Householder's null-space method for exact solution and present a complete exposition of the new approach. A detailed comparison with well-established matrix inversion methods in literature is also given.
Stability Analysis for Stochastic Optimization Problems
无
2007-01-01
Stochastic optimization offers a means of considering the objectives and constrains with stochastic parameters. However, it is generally difficult to solve the stochastic optimization problem by employing conventional methods for nonlinear programming when the number of random variables involved is very large. Neural network models and algorithms were applied to solve the stochastic optimization problem on the basis of the stability theory. Stability for stochastic programs was discussed. If random vector sequence converges to the random vector in the original problem in distribution, the optimal value of the corresponding approximation problems converges to the optimal value of the original stochastic optimization problem.
Kramers-Wannier duality applied to the boolean satifiability problem
Mitchell, Joe; Hsu, Benjamin; Galitski, Victor
2014-03-01
Kramers-Wannier duality, first considered in 1941, is an exact technique used in statistical mechanics to relate two models together through an order-disorder transformation, and thereby study their structure and critical phenomena. The boolean satisfiability problem is one of the most important problems in computer science, specifically complexity theory; it is the first proven NP-complete problem. Using a mapping to a multi-spin Ising model in the limit of zero temperature, we present an application of Kramers-Wannier duality to this problem. This results in a novel relationship between solving the boolean satisfiability counting problem and a different computational problem: listing the non-negative solutions to a particular system of linear integer equations. This mapping relates the complexity of the two problems. We discuss the generality of Kramers-Wannier duality and its possible application to other computational problems. This research was supported by NSF-CAREER award No. DMR-0847224 and Simons Foundation.
Quantum Counterfeit Coin Problems
Iwama, Kazuo; Raymond, Rudy; Teruyama, Junichi
2010-01-01
The counterfeit coin problem requires us to find all false coins from a given bunch of coins using a balance scale. We assume that the balance scale gives us only ``balanced'' or ``tilted'' information and that we know the number k of false coins in advance. The balance scale can be modeled by a certain type of oracle and its query complexity is a measure for the cost of weighing algorithms (the number of weighings). In this paper, we study the quantum query complexity for this problem. Let Q(k,N) be the quantum query complexity of finding all k false coins from the N given coins. We show that for any k and N such that k < N/2, Q(k,N)=O(k^{1/4}), contrasting with the classical query complexity, \\Omega(k\\log(N/k)), that depends on N. So our quantum algorithm achieves a quartic speed-up for this problem. We do not have a matching lower bound, but we show some evidence that the upper bound is tight: any algorithm, including our algorithm, that satisfies certain properties needs \\Omega(k^{1/4}) queries.
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