An ellipsoidal branch and bound algorithm for global optimization
Hager, William; Phan, Dzung
2009-01-01
A branch and bound algorithm is developed for global optimization. Branching in the algorithm is accomplished by subdividing the feasible set using ellipses. Lower bounds are obtained by replacing the concave part of the objective function by an affine underestimate. A ball approximation algorithm, obtained by generalizing of a scheme of Lin and Han, is used to solve the convex relaxation of the original problem. The ball approximation algorithm is compared to SEDUMI as well as to gradient pr...
Kodiak: An Implementation Framework for Branch and Bound Algorithms
Smith, Andrew P.; Munoz, Cesar A.; Narkawicz, Anthony J.; Markevicius, Mantas
2015-01-01
Recursive branch and bound algorithms are often used to refine and isolate solutions to several classes of global optimization problems. A rigorous computation framework for the solution of systems of equations and inequalities involving nonlinear real arithmetic over hyper-rectangular variable and parameter domains is presented. It is derived from a generic branch and bound algorithm that has been formally verified, and utilizes self-validating enclosure methods, namely interval arithmetic and, for polynomials and rational functions, Bernstein expansion. Since bounds computed by these enclosure methods are sound, this approach may be used reliably in software verification tools. Advantage is taken of the partial derivatives of the constraint functions involved in the system, firstly to reduce the branching factor by the use of bisection heuristics and secondly to permit the computation of bifurcation sets for systems of ordinary differential equations. The associated software development, Kodiak, is presented, along with examples of three different branch and bound problem types it implements.
A BRANCH AND BOUND ALGORITHM FOR SEPARABLE CONCAVE PROGRAMMING
Institute of Scientific and Technical Information of China (English)
Hong-gang Xue; Cheng-xian; Feng-min Xu
2004-01-01
In this paper, we propose a new branch and bound algorithm for the solution of large scale separable concave programming problems. The largest distance bisection (LDB)technique is proposed to divide rectangle into sub-rectangles when one problem is branched into two subproblems. It is proved that the LDB method is a normal rectangle subdivision(NRS). Numerical tests on problems with dimensions from 100 to 10000 show that the proposed branch and bound algorithm is efficient for solving large scale separable concave programming problems, and convergence rate is faster than ω-subdivision method.
Constrained branch-and-bound algorithm for image registration
Institute of Scientific and Technical Information of China (English)
JIN Jian-qiu; WANG Zhang-ye; PENG Qun-sheng
2005-01-01
In this paper, the authors propose a refined Branch-and-Bound algorithm for affine-transformation based image registration. Given two feature point-sets in two images respectively, the authors first extract a sequence of high-probability matched point-pairs by considering well-defined features. Each resultant point-pair can be regarded as a constraint in the search space of Branch-and-Bound algorithm guiding the search process. The authors carry out Branch-and-Bound search with the constraint of a pair-point selected by using Monte Carlo sampling according to the match measures of point-pairs. If such one cannot lead to correct result, additional candidate is chosen to start another search. High-probability matched point-pairs usually results in fewer loops and the search process is accelerated greatly. Experimental results verify the high efficiency and robustness of the author's approach.
Branch and Bound algorithms in greenhouse climate control
Hermelink, Marleen
2016-01-01
The horticultural sector has become an increasingly important sector of food production, for which greenhouse climate control plays a vital role in improving its sustainability. One of the methods to control the greenhouse climate is Model Predictive Control, which can be optimized through a branch and bound algorithm. The application of the algorithm in literature is examined and analyzed through small examples, and later extended to greenhouse climate simulation. A comparison is ma...
A branch and bound algorithm for the global optimization of Hessian Lipschitz continuous functions
Fowkes, Jaroslav M.
2012-06-21
We present a branch and bound algorithm for the global optimization of a twice differentiable nonconvex objective function with a Lipschitz continuous Hessian over a compact, convex set. The algorithm is based on applying cubic regularisation techniques to the objective function within an overlapping branch and bound algorithm for convex constrained global optimization. Unlike other branch and bound algorithms, lower bounds are obtained via nonconvex underestimators of the function. For a numerical example, we apply the proposed branch and bound algorithm to radial basis function approximations. © 2012 Springer Science+Business Media, LLC.
Revisiting the upper bounding process in a safe Branch and Bound algorithm
Goldsztejn, Alexandre; Michel, Claude; Rueher, Michel
2008-01-01
Finding feasible points for which the proof succeeds is a critical issue in safe Branch and Bound algorithms which handle continuous problems. In this paper, we introduce a new strategy to compute very accurate approximations of feasible points. This strategy takes advantage of the Newton method for under-constrained systems of equations and inequalities. More precisely, it exploits the optimal solution of a linear relaxation of the problem to compute efficiently a promising upper bound. First experiments on the Coconuts benchmarks demonstrate that this approach is very effective.
A Branch and Bound Reduced Algorithm for Quadratic Programming Problems with Quadratic Constraints
Directory of Open Access Journals (Sweden)
Yuelin Gao
2013-01-01
Full Text Available We propose a branch and bound reduced algorithm for quadratic programming problems with quadratic constraints. In this algorithm, we determine the lower bound of the optimal value of original problem by constructing a linear relaxation programming problem. At the same time, in order to improve the degree of approximation and the convergence rate of acceleration, a rectangular reduction strategy is used in the algorithm. Numerical experiments show that the proposed algorithm is feasible and effective and can solve small- and medium-sized problems.
A Branch and Bound Algorithm for the Protein Folding Problem in the HP Lattice Model
Institute of Scientific and Technical Information of China (English)
Mao Chen; Wen-Qi Huang
2005-01-01
A branch and bound algorithm is proposed for the two-dimensional protein folding problem in the HP lattice model. In this algorithm, the benefit of each possible location of hydrophobic monomers is evaluated and only promising nodes are kept for further branching at each level. The proposed algorithm is compared with other well-known methods for 10 benchmark sequences with lengths ranging from 20 to 100 monomers. The results indicate that our method is a very efficient and promising tool for the protein folding problem.
On estimating workload in branch-and-bound global optimization algorithms
Berenguel, J.L.; Casado, L.G.; Garcia, I.; Hendrix, E.M.T.
2013-01-01
In general, solving Global Optimization (GO) problems by Branch-and-Bound (B&B) requires a huge computational capacity. Parallel execution is used to speed up the computing time. As in this type of algorithms, the foreseen computational workload (number of nodes in the B&B tree) changes dyna
Parallel Branch and Bound Algorithm - A comparison between serial, OpenMP and MPI implementations
International Nuclear Information System (INIS)
This paper presents a comparison of an extended version of the regular Branch and Bound algorithm previously implemented in serial with a new parallel implementation, using both MPI (distributed memory parallel model) and OpenMP (shared memory parallel model). The branch-and-bound algorithm is an enumerative optimization technique, where finding a solution to a mixed integer programming (MIP) problem is based on the construction of a tree where nodes represent candidate problems and branches represent the new restrictions to be considered. Through this tree all integer solutions of the feasible region of the problem are listed explicitly or implicitly ensuring that all the optimal solutions will be found. A common approach to solve such problems is to convert sub-problems of the mixed integer problem to linear programming problems, thereby eliminating some of the integer constraints, and then trying to solve that problem using an existing linear program approach. The paper describes the general branch and bound algorithm used and provides details on the implementation and the results of the comparison.
Nakariyakul, Songyot; Casasent, David
2006-10-01
Detection of skin tumors on chicken carcasses is considered. A chicken skin tumor consists of an ulcerous lesion region surrounded by a region of thickened-skin. We use a new adaptive branch-and-bound (ABB) feature selection algorithm to choose only a few useful wavebands from hyperspectral data for use in a real-time multispectral camera. The ABB algorithm selects an optimal feature subset and is shown to be much faster than any other versions of the branch and bound algorithm. We found that the spectral responses of the lesion and the thickened-skin regions of tumors are considerably different; thus we train our feature selection algorithm to separately detect the lesion regions and thickened-skin regions of tumors. We then fuse the two HS detection results of lesion and thickened-skin regions to reduce false alarms. Initial results on six hyperspectral cubes show that our method gives an excellent tumor detection rate and a low false alarm rate.
A Branch and Bound Algorithm for a Class of Biobjective Mixed Integer Programs
DEFF Research Database (Denmark)
Stidsen, Thomas Riis; Andersen, Kim Allan; Dammann, Bernd
2014-01-01
Pareto-optimal front). In this paper, we first give a survey of the newly developed branch and bound methods for solving MOMIP problems. After that, we propose a new branch and bound method for solving a subclass of MOMIP problems, where only two objectives are allowed, the integer variables are binary...
A Branch and Bound Algorithm for Project Scheduling Problem with Spatial Resource Constraints
Directory of Open Access Journals (Sweden)
Shicheng Hu
2015-01-01
Full Text Available With respect to the block assembly schedule in a shipbuilding enterprise, a spatial resource constrained project scheduling problem (SRCPSP is proposed, which aims to minimize the makespan of a project under the constraints of the availability of a two-dimensional spatial resource and the precedence relationship between tasks. In order to solve SRCPSP to the optimum, a branch and bound algorithm (BB is developed. For the BB-SRCPSP, first, an implicitly enumerative branch scheme is presented. Secondly, a precedence based lower bound, as well as an effective dominance rule, is employed for pruning. Next, a heuristic based algorithm is used to decide the order of a node to be selected for expansion such that the efficiency of the algorithm is further improved. In addition, a maximal space based arrangement is applied to the configuration of the areas required each day in an available area. Finally, the simulation experiment is conducted to illustrate the effectiveness of the BB-SRCPSP.
Institute of Scientific and Technical Information of China (English)
Belgacem BETTAYEB; Imed KACEM; Kondo H.ADJALLAH
2008-01-01
This article investigates identical parallel machines scheduling with family setup times. Theobjective function being the weighted sum of completion times, the problem is known to be strongly NP-hard. We propose a constructive heuristic algorithm and three complementary lower bounds. Two of these bounds proceed by elimination of setup times or by distributing each of them to jobs of the corresponding family, while the third one is based on a lagrangian relaxation. The bounds and the heuristic are incorporated into a branch-and-bound algorithm. Experimental results obtained outperform those of the methods presented in previous works, in term of size of solved problems.
A simple but usually fast branch-and-bound algorithm for the capacitated facility location problem
DEFF Research Database (Denmark)
Görtz, Simon; Klose, Andreas
2012-01-01
This paper presents a simple branch-and-bound method based on Lagrangean relaxation and subgradient optimization for solving large instances of the capacitated facility location problem (CFLP) to optimality. To guess a primal solution to the Lagrangean dual, we average solutions to the Lagrangean...
Directory of Open Access Journals (Sweden)
Shangchia Liu
2015-01-01
Full Text Available In the field of distributed decision making, different agents share a common processing resource, and each agent wants to minimize a cost function depending on its jobs only. These issues arise in different application contexts, including real-time systems, integrated service networks, industrial districts, and telecommunication systems. Motivated by its importance on practical applications, we consider two-agent scheduling on a single machine where the objective is to minimize the total completion time of the jobs of the first agent with the restriction that an upper bound is allowed the total completion time of the jobs for the second agent. For solving the proposed problem, a branch-and-bound and three simulated annealing algorithms are developed for the optimal solution, respectively. In addition, the extensive computational experiments are also conducted to test the performance of the algorithms.
Branch and Bound Experiments in Convex Nonlinear Integer Programming
Omprakash K. Gupta; Ravindran, A
1985-01-01
The branch and bound principle has long been established as an effective computational tool for solving mixed integer linear programming problems. This paper investigates the computational feasibility of branch and bound methods in solving convex nonlinear integer programming problems. The efficiency of a branch and bound method often depends on the rules used for selecting the branching variables and branching nodes. Among others, the concepts of pseudo-costs and estimations are implemented ...
A tool for simulating parallel branch-and-bound methods
Golubeva, Yana; Orlov, Yury; Posypkin, Mikhail
2016-01-01
The Branch-and-Bound method is known as one of the most powerful but very resource consuming global optimization methods. Parallel and distributed computing can efficiently cope with this issue. The major difficulty in parallel B&B method is the need for dynamic load redistribution. Therefore design and study of load balancing algorithms is a separate and very important research topic. This paper presents a tool for simulating parallel Branchand-Bound method. The simulator allows one to run load balancing algorithms with various numbers of processors, sizes of the search tree, the characteristics of the supercomputer's interconnect thereby fostering deep study of load distribution strategies. The process of resolution of the optimization problem by B&B method is replaced by a stochastic branching process. Data exchanges are modeled using the concept of logical time. The user friendly graphical interface to the simulator provides efficient visualization and convenient performance analysis.
A tool for simulating parallel branch-and-bound methods
Directory of Open Access Journals (Sweden)
Golubeva Yana
2016-01-01
Full Text Available The Branch-and-Bound method is known as one of the most powerful but very resource consuming global optimization methods. Parallel and distributed computing can efficiently cope with this issue. The major difficulty in parallel B&B method is the need for dynamic load redistribution. Therefore design and study of load balancing algorithms is a separate and very important research topic. This paper presents a tool for simulating parallel Branchand-Bound method. The simulator allows one to run load balancing algorithms with various numbers of processors, sizes of the search tree, the characteristics of the supercomputer’s interconnect thereby fostering deep study of load distribution strategies. The process of resolution of the optimization problem by B&B method is replaced by a stochastic branching process. Data exchanges are modeled using the concept of logical time. The user friendly graphical interface to the simulator provides efficient visualization and convenient performance analysis.
PICO: An Object-Oriented Framework for Branch and Bound
Energy Technology Data Exchange (ETDEWEB)
ECKSTEIN,JONATHAN; HART,WILLIAM E.; PHILLIPS,CYNTHIA A.
2000-12-01
This report describes the design of PICO, a C++ framework for implementing general parallel branch-and-bound algorithms. The PICO framework provides a mechanism for the efficient implementation of a wide range of branch-and-bound methods on an equally wide range of parallel computing platforms. We first discuss the basic architecture of PICO, including the application class hierarchy and the package's serial and parallel layers. We next describe the design of the serial layer, and its central notion of manipulating subproblem states. Then, we discuss the design of the parallel layer, which includes flexible processor clustering and communication rates, various load balancing mechanisms, and a non-preemptive task scheduler running on each processor. We describe the application of the package to a branch-and-bound method for mixed integer programming, along with computational results on the ASCI Red massively parallel computer. Finally we describe the application of the branch-and-bound mixed-integer programming code to a resource constrained project scheduling problem for Pantex.
DEFF Research Database (Denmark)
Clausen, Jens; Zilinskas, A,
2002-01-01
We consider the problem of optimizing a Lipshitzian function. The branch and bound technique is a well-known solution method, and the key components for this are the subdivision scheme, the bound calculation scheme, and the initialization. For Lipschitzian optimization, the bound calculations...... are based on the sampling of function values. We propose a branch and bound algorithm based on regular simplexes. Initially, the domain in question is covered with regular simplexes, and our subdivision scheme maintains this property. The bound calculation becomes both simple and efficient, and we describe...
Brucker, P.; Hilbig, T.; Hurink, J.L.
1999-01-01
Positive and negative time-lags are general timing restrictions between the starting times of jobs which have been introduced by Roy in connection with the Metra Potential Method. They allow the consideration of positive and negative time-lags between the starting times of jobs. It is shown that com
On longest edge division in simplicial branch and bound
Herrera, J.F.R.; Casado, L.G.; Hendrix, E.M.T.
2014-01-01
Simplicial partitions are suitable to divide a bounded area in branch and bound. In the iterative refinement process, a popular strategy is to divide simplices by their longest edge, thus avoiding needle-shaped simplices. A range of possibilities arises when the number of longest edges in a simplex
A branch-and-bound algorithm for single-machine earliness-tardiness scheduling with idle time
Hoogeveen, J.A.; Velde, van de S.L.
1996-01-01
We address the NP-hard single-machine problem of scheduling n independent jobs so as to minimize the sum of α times total completion time and β times total earliness with β > α, which can be rewritten as an earliness–tardiness problem. Postponing jobs by leaving the machine idle may then be advantag
Institute of Scientific and Technical Information of China (English)
孙娟; 盛红波; 孙小玲
2007-01-01
In this paper,a branch-and-bound method for solving multi-dimensional quadratic 0-1 knapsack problems was studied.The method was based on the Lagrangian relaxation and the surrogate constraint technique for finding feasible solutions.The Lagrangian relaxations were solved with the maximum-flow algorithm and the Lagrangian bounds Was determined with the outer approximation method.Computational results show the efficiency of the proposed method for multi-dimensional quadratic 0-1 knapsack problems.
Computational Protein Design Using AND/OR Branch-and-Bound Search.
Zhou, Yichao; Wu, Yuexin; Zeng, Jianyang
2016-06-01
The computation of the global minimum energy conformation (GMEC) is an important and challenging topic in structure-based computational protein design. In this article, we propose a new protein design algorithm based on the AND/OR branch-and-bound (AOBB) search, a variant of the traditional branch-and-bound search algorithm, to solve this combinatorial optimization problem. By integrating with a powerful heuristic function, AOBB is able to fully exploit the graph structure of the underlying residue interaction network of a backbone template to significantly accelerate the design process. Tests on real protein data show that our new protein design algorithm is able to solve many problems that were previously unsolvable by the traditional exact search algorithms, and for the problems that can be solved with traditional provable algorithms, our new method can provide a large speedup by several orders of magnitude while still guaranteeing to find the global minimum energy conformation (GMEC) solution. PMID:27167301
Directory of Open Access Journals (Sweden)
Denise Sato Yamashita
2007-12-01
Full Text Available Em um estudo anterior (YAMASHITA; MORABITO, 2007a, foi proposto um algoritmo exato para resolver o problema de programação de projetos com custo de disponibilidade de recursos, considerando múltiplos modos de execução para as atividades. O algoritmo é uma adaptação de outro algoritmo exato da literatura para o caso particular do problema em que só existe um modo de executar as atividades. No presente estudo, é proposto um novo algoritmo exato baseado no método branch-and-bound para tratar do problema com múltiplos modos de execução. Como o problema é NP-difícil, o algoritmo é viável computacionalmente apenas para resolver exemplares de tamanho moderado. Diversos testes computacionais utilizando o programa gerador Progen da literatura foram realizados para comparar o desempenho do algoritmo proposto com o algoritmo anterior e também com o aplicativo CPLEX. Os resultados obtidos mostram que a versão atual do algoritmo é competitiva com os outros métodos, e estimulam a pesquisa e o desenvolvimento de versões mais elaboradas deste algoritmo.In a recent study (YAMASHITA; MORABITO, 2007a, it was proposed an exact algorithm to solve problems of resource-constrained project scheduling with resource availability costs under multiple modes of execution. That algorithm is an adaptation of another exact algorithm recorded in the literature for the particular case where there is only a single mode for executing the tasks. In the present study, we propose a new exact algorithm based on the branch and bound method to deal with multiple performing modes problem. Since the problem is NP-hard, the algorithm is computationally viable only for problems of moderate size. Numerous computational tests using the generator ProGen were run to compare the performance of the proposed algorithm with the former algorithm and with the CPLEX software. The results show that the proposed version of the algorithm is competitive with the other methods and
Recursive algorithms, branching coefficients and applications
Lyakhovsky, Vladimir
2010-01-01
Recurrent relations for branching coefficients in affine Lie algebras integrable highest weight modules are studied. The decomposition algorithm based on the injection fan technique is adopted to the situation where the Weyl denominator becomes singular with respect to a reductive subalgebra. We study some modifications of the injection fan technique and demonstrate that it is possible to define the "subtracted fans" that play the role similar to the original ones. Possible applications of subtracted fans in CFT models are considered.
A branch and bound approach for minimizing the energy consumption of an electrical vehicle
Merakeb, Abdelkader; Messine, Frédéric
2013-01-01
National audience In this paper we discuss about the way to approximate the solution of an optimal control problem with a switched command. Our Method is based on a discretization technique associated with a Branch and Bound algorithm. The problem that we focus on is the minimization of the consumption of the energy of an electrical vehicle during some imposed displacements.
Some distance bounds of branching processes and their diffusion limits
Kammerer, Niels B
2010-01-01
We compute exact values respectively bounds of "distances" - in the sense of (transforms of) power divergences and relative entropy - between two discrete-time Galton-Watson branching processes with immigration GWI for which the offspring as well as the immigration is arbitrarily Poisson-distributed (leading to arbitrary type of criticality). Implications for asymptotic distinguishability behaviour in terms of contiguity and entire separation of the involved GWI are given, too. Furthermore, we determine the corresponding limit quantities for the context in which the two GWI converge to Feller-type branching diffusion processes, as the time-lags between observations tend to zero. Some applications to (static random environment like) Bayesian decision making and Neyman-Pearson testing are presented as well.
Dimitrakakis, Christos
2009-01-01
There has been a lot of recent work on Bayesian methods for reinforcement learning exhibiting near-optimal online performance. The main obstacle facing such methods is that in most problems of interest, the optimal solution involves planning in an infinitely large tree. However, it is possible to obtain stochastic lower and upper bounds on the value of each tree node. This enables us to use stochastic branch and bound algorithms to search the tree efficiently. This paper proposes two such algorithms and examines their complexity in this setting.
Directory of Open Access Journals (Sweden)
Ricardo Alberto Hincapie-Isaza
2011-06-01
Full Text Available En este trabajo se plantea una metodología para la solución del problema delplaneamiento de sistemas secundarios de distribución considerando un modelode programación lineal entero mixto (PLEM, el cual considera la ubicación y dimensionamiento de transformadores de distribución, el dimensionamientoy rutas de circuitos secundarios y sus costos variables. Para la solución delproblema se emplea el algoritmo Branch and Bound. Los resultados obtenidosen un sistema de prueba empleado en la literatura especializada muestran lavalidez y efectividad de la metodología propuesta.This paper presents a methodology for solving secondary distribution systems planning problem as a mixed integer linear programming problem (MILP. The algorithm takes into account several design issues such as the capacity and location of distribution transformers and secondary feeders. Variable costs of secondary feeders are also considered. The problem is solved using branch and bound algorithm. Numerical results show that the mathematical model and the solution technique are effective for this kind of problems.
Saad, Shakila; Wan Jaafar, Wan Nurhadani; Jamil, Siti Jasmida
2013-04-01
The standard Traveling Salesman Problem (TSP) is the classical Traveling Salesman Problem (TSP) while Multiple Traveling Salesman Problem (MTSP) is an extension of TSP when more than one salesman is involved. The objective of MTSP is to find the least costly route that the traveling salesman problem can take if he wishes to visit exactly once each of a list of n cities and then return back to the home city. There are a few methods that can be used to solve MTSP. The objective of this research is to implement an exact method called Branch-and-Bound (B&B) algorithm. Briefly, the idea of B&B algorithm is to start with the associated Assignment Problem (AP). A branching strategy will be applied to the TSP and MTSP which is Breadth-first-Search (BFS). 11 nodes of cities are implemented for both problem and the solutions to the problem are presented.
DEFF Research Database (Denmark)
Gadegaard, Sune Lauth; Ehrgott, Matthias; Nielsen, Lars Relund
2016-01-01
Most real-world optimization problems are of a multi-objective nature, involving objectives which are conflicting and incomparable. Solving a multi-objective optimization problem requires a method which can generate the set of rational compromises between the objectives. In this paper, we propose...... two distinct bound set based branch-and-cut algorithms for bi-objective combinatorial optimization problems, based on implicitly and explicitly stated lower bound sets, respectively. The algorithm based on explicitly given lower bound sets computes for each branching node a lower bound set...... and compares it to an upper bound set. The implicit bound set based algorithm, on the other hand, fathoms branching nodes by generating a single point on the lower bound set for each local nadir point. We outline several approaches for fathoming branching nodes and we propose an updating scheme for the lower...
Using the primal-dual interior point algorithm within the branch-price-and-cut method
Munari, P.; Gondzio, J.
2013-01-01
Branch-price-and-cut has proven to be a powerful method for solving integer programming problems. It combines decomposition techniques with the generation of both columns and valid inequalities and relies on strong bounds to guide the search in the branch-and-bound tree. In this paper, we present how to improve the performance of a branch-price-and-cut method by using the primal-dual interior point algorithm. We discuss in detail how to deal with the challenges of using the interior point alg...
An exercise in transformational programming: Backtracking and Branch-and-Bound
Fokkinga, M.M.
1991-01-01
We present a formal derivation of program schemes that are usually called Backtracking programs and Branch-and-Bound programs. The derivation consists of a series of transformation steps, specifically algebraic manipulations, on the initial specification until the desired programs are obtained. The
Recursive Branching Simulated Annealing Algorithm
Bolcar, Matthew; Smith, J. Scott; Aronstein, David
2012-01-01
solution, and the region from which new configurations can be selected shrinks as the search continues. The key difference between these algorithms is that in the SA algorithm, a single path, or trajectory, is taken in parameter space, from the starting point to the globally optimal solution, while in the RBSA algorithm, many trajectories are taken; by exploring multiple regions of the parameter space simultaneously, the algorithm has been shown to converge on the globally optimal solution about an order of magnitude faster than when using conventional algorithms. Novel features of the RBSA algorithm include: 1. More efficient searching of the parameter space due to the branching structure, in which multiple random configurations are generated and multiple promising regions of the parameter space are explored; 2. The implementation of a trust region for each parameter in the parameter space, which provides a natural way of enforcing upper- and lower-bound constraints on the parameters; and 3. The optional use of a constrained gradient- search optimization, performed on the continuous variables around each branch s configuration in parameter space to improve search efficiency by allowing for fast fine-tuning of the continuous variables within the trust region at that configuration point.
Design of planar articulated mechanisms using branch and bound
DEFF Research Database (Denmark)
Stolpe, Mathias; Kawamoto, Atsushi
2005-01-01
This paper considers an optimization model and a solution method for the design of two-dimensional mechanical mechanisms. The mechanism design problem is modeled as a nonconvex mixed integer program which allows the optimal topology and geometry of the mechanism to be determined simultaneously. T...
Design of planar articulated mechanisms using branch and bound
DEFF Research Database (Denmark)
Stolpe, Mathias; Kawamoto, Atsushi
2004-01-01
This paper considers an optimization model and a solution method for the design of two-dimensional mechanical mechanisms. The mechanism design problem is modeled as a nonconvex mixed integer program which allows the optimal topology and geometry of the mechanism to be determined simultaneously. T...
An exercise in transformational programming: Backtracking and Branch-and-Bound
Fokkinga, M.M.
1991-01-01
We present a formal derivation of program schemes that are usually called Backtracking programs and Branch-and-Bound programs. The derivation consists of a series of transformation steps, specifically algebraic manipulations, on the initial specification until the desired programs are obtained. The well-known notions of linear recursion and tail recursion are extended, for structures, to elementwise linear recursion and elementwise tail recursion; and a transformation between them is derived ...
Bounds of Deviation for Branching Chains in Random Environments
Institute of Scientific and Technical Information of China (English)
Wei Gang WANG
2011-01-01
We consider non-extinct branching processes in general random environments. Under the condition of means and second moments of each generation being bounded, we give the upper bounds and lower bounds for some form deviations of the process.
A branch-and-cut algorithm for the symmetric two-echelon capacitated vehicle routing problem
DEFF Research Database (Denmark)
Jepsen, Mads Kehlet; Spoorendonk, Simon; Røpke, Stefan
2013-01-01
This paper presents an exact method for solving the symmetric two-echelon capacitated vehicle routing problem, a transportation problem concerned with the distribution of goods from a depot to a set of customers through a set of satellite locations. The presented method is based on an edge flow...... model that is a relaxation and provides a valid lower bound. A specialized branching scheme is employed to obtain feasible solutions. Out of a test set of 93 instances the algorithm is able to solve 47 to optimality surpassing previous exact algorithms....
Managing Water Quality under Uncertainty: Application of a New Stochastic Branch and Bound Method
Lence, B.J.; Ruszczynski, A.
1996-01-01
The problem of water quality management under uncertain emission levels, reaction rates and pollutant transport is considered. Various performance measures: reliability, resiliency and vulnerability are taken into account. A general methodology for finding a cost-effective water quality management program is developed. The approach employs a new idea of the stochastic branch and bound method, which combines random estimates of the performance for subsets of decisions with iterative refinement...
Malone, Brandon; Hansen, Eric A; Bridges, Susan
2012-01-01
Previous work has shown that the problem of learning the optimal structure of a Bayesian network can be formulated as a shortest path finding problem in a graph and solved using A* search. In this paper, we improve the scalability of this approach by developing a memory-efficient heuristic search algorithm for learning the structure of a Bayesian network. Instead of using A*, we propose a frontier breadth-first branch and bound search that leverages the layered structure of the search graph of this problem so that no more than two layers of the graph, plus solution reconstruction information, need to be stored in memory at a time. To further improve scalability, the algorithm stores most of the graph in external memory, such as hard disk, when it does not fit in RAM. Experimental results show that the resulting algorithm solves significantly larger problems than the current state of the art.
A branch-and-cut algorithm for the bandwidth packing problem
Energy Technology Data Exchange (ETDEWEB)
Park, S.; Park, K.; Kang, S.
1994-12-31
We consider the bandwidth packing problem, that arises in the telecommunication network. The problem is to determine the set of calls and the assignment of them to the paths in an arc capacitated network to maximize profit. The problem is formulated by using path variables. To solve LP relaxation, an efficient column generation technique is proposed. Moreover, modified cover inequality is used to strengthen the formulation. The algorithm incorporates the column generation technique and the strong cutting plane approach into the branch-and-bound scheme. We test the proposed algorithm on several problem instances. The results show that the algorithm can be used to solve the problems to optimality within reasonably small time limits.
A branch-and-price algorithm for the capacitated facility location problem
DEFF Research Database (Denmark)
Klose, Andreas; Görtz, Simon
2007-01-01
operating and transportation costs. A number of solution approaches based on Lagrangean relaxation and subgradient optimization has been proposed for this problem. Subgradient optimization does not provide a primal (fractional) optimal solution to the corresponding master problem. However, in order...... to compute optimal solutions to large or difficult problem instances by means of a branch-and-bound procedure information about such a primal fractional solution can be advantageous. In this paper, a (stabilized) column generation method is, therefore, employed in order to solve a corresponding master...... problem exactly. The column generation procedure is then employed within a branch-and-price algorithm for computing optimal solutions to the CFLP. Computational results are reported for a set of larger and difficult problem instances....
Variables Bounding Based Retiming Algorithm
Institute of Scientific and Technical Information of China (English)
宫宗伟; 林争辉; 陈后鹏
2002-01-01
Retiming is a technique for optimizing sequential circuits. In this paper, wediscuss this problem and propose an improved retiming algorithm based on variables bounding.Through the computation of the lower and upper bounds on variables, the algorithm can signi-ficantly reduce the number of constraints and speed up the execution of retiming. Furthermore,the elements of matrixes D and W are computed in a demand-driven way, which can reducethe capacity of memory. It is shown through the experimental results on ISCAS89 benchmarksthat our algorithm is very effective for large-scale sequential circuits.
Directory of Open Access Journals (Sweden)
Mukhacheva E.A.
2000-01-01
Full Text Available Two algorithms for the one-dimensional cutting problem, namely, a modified branch-and-bound method (exact method and a heuristic sequential value correction method are suggested. In order to obtain a reliable assessment of the efficiency of the algorithms, hard instances of the problem were considered and from the computational experiment it seems that the efficiency of the heuristic method appears to be superior to that of the exact one, taking into account the computing time of the latter. A detailed description of the two methods is given along with suggestions for their improvements.
Institute of Scientific and Technical Information of China (English)
薛宏刚; 张川; 胡春萍; 徐成贤
2011-01-01
In this paper, we consider the portfolio optimal problem under block trading. As the decrease of marginal transaction cost under block trading, we establish the mean-variance portfolio optimization model and the corresponding algorithm by means of fit transaction cost function with linear and concave form. Computational results are presented by considering the stocks involved in Hang Seng Index to show that: The efficient frontier under block trading is between that with linear transaction cost and without transaction cost; The investment risk can be eliminated by portfolio diversification, but the effect of that is dilute under block trading; In terms of linear transaction cost, the greater the transaction cost under block trading, the higher the portfolio concentration.%由于大宗交易下边际交易费用递减,因此用线性加凹的函数拟合实际交易费用函数,建立了均值-方差框架下的组合优化模型并给出了相应的求解算法.通过对恒生指数样本股的实证分析发现:考虑大宗交易的组合有效边缘介于线性交易费用和无交易费用的组合有效边缘之间；大宗交易稀释了“分散化降低风险”的效应；大宗交易下交易费用越大,相对于线性交易费用而言组合集中度越高.
A Branch-and-Cut Algorithm for Elementary Shortest Path Problem with Resource Constraints
DEFF Research Database (Denmark)
Jepsen, Mads Kehlet; Petersen, Bjørn; Spoorendonk, Simon
The elementary shortest path with resource constraints are commonly solved with dynamic programming algorithms. We present a branch-and-cut algorithm for the undirected version. Two types of resources are discussed: A capacity and a fixed charge resource. The former is the subproblem of the capac...... of the capacitated vehicle routing problem and the latter is for the split delivery version....
International Nuclear Information System (INIS)
Highlights: • A hierarchical MILP method for optimal design of energy supply systems is proposed. • Lower bounds for the optimal value of the objective function are evaluated. • Bounding operations using the lower bounds are proposed. • The proposed method is implemented into open and commercial MILP solvers. • Validity and effectiveness of the proposed method are clarified by case studies. - Abstract: To attain the highest performance of energy supply systems, it is necessary to rationally determine types, capacities, and numbers of equipment in consideration of their operational strategies corresponding to seasonal and hourly variations in energy demands. In the combinatorial optimization method based on the mixed-integer linear programming (MILP), integer variables are used to express the selection, numbers, and on/off status of operation of equipment, and the number of these variables increases with those of equipment and periods for variations in energy demands, and affects the computation efficiency significantly. In this paper, a MILP method utilizing the hierarchical relationship between design and operation variables is proposed to solve the optimal design problem of energy supply systems efficiently: At the upper level, the optimal values of design variables are searched by the branch and bound method; At the lower level, the values of operation variables are optimized independently at each period by the branch and bound method under the values of design variables given tentatively during the search at the upper level; Lower bounds for the optimal value of the objective function to be minimized are evaluated, and are utilized for the bounding operations at both the levels. This method is implemented into open and commercial MILP solvers. Illustrative and practical case studies on the optimal design of cogeneration systems are conducted, and the validity and effectiveness of the proposed method are clarified
A branch-and-cut algorithm for the elementary shortest path problem with resource constraints
DEFF Research Database (Denmark)
Jepsen, Mads Kehlet; Petersen, Bjørn; Spoorendonk, Simon
The elementary shortest path with resource constraints have commonly been solved with dynamic programming algorithms. Assuming an undirected graph, we present a compact formulation of this problem and a branch-and-cut algorithm to solve it. Two types of resources are discussed: a capacity...... and a fixed charge resource. The former is the subproblem of the capacitated vehicle routing problem and the latter is from the split delivery version. Computational results are presented and compared to dynamic programming algorithms....
New facets and a branch-and-cut algorithm for the weighted clique problem
DEFF Research Database (Denmark)
Sørensen, Michael Malmros
2004-01-01
We consider a polyhedral approach to the weighted maximal b-clique problem. Given a node- and edge-weighted complete graph the problem is to find a complete subgraph (clique) with no more than b nodes such that the sum of the weights of all nodes and edges in the clique is maximal. We introduce...... defining inequalities in a branch-and-cut algorithm for the problem. We give a description of this algorithm, including some separation procedures, and present the computational results for different sets of test problems. The computation times that are obtained indicate that this algorithm is more...... efficient than previously described algorithms for the problem. Udgivelsesdato: APR 1...
New Facets and a Branch-and-Cut Algorithm for the Weighted Clique Problem
DEFF Research Database (Denmark)
Sørensen, Michael Malmros
2001-01-01
We consider a polyhedral approach to the weighted maximal b-clique problem. Given a node- and edge-weighted complete graph the problem is to find a complete subgraph (clique) with no more than b nodes such that the sum of the weights of all nodes and edges in the clique is maximal. We introduce...... of facet defining inequalities in a branch-and-cut algorithm for the problem. We give a description of this algorithm, including some separation procedures, and present the computational results for different sets of test problems. The computation times that are obtained indicate that this algorithm...... is more efficient than previously described algorithms for the problem....
Lower bounds for 1-, 2- and 3-dimensional on-line bin packing algorithms
G. Galambos; A. van Vliet (André)
1994-01-01
textabstractIn this paper we discuss lower bounds for the asymptotic worst case ratio of on-line algorithms for different kind of bin packing problems. Recently, Galambos and Frenk gave a simple proof of the 1.536 ... lower bound for the 1-dimensional bin packing problem. Following their ideas, we p
Monotonically convergent algorithms for bounded quantum controls
Turinici, Gabriel
2003-01-01
International audience Most of the numerical simulations in quantum (bilinear) control have used one of the monotonically convergent algorithms of Krotov (introduced by Tannor et al. (Tannor et al., 1992)) or of Zhu & Rabitz (Zhu and Rabitz, 1998). Recently(Maday and Turinici, 2002), new schemes have been designed that enlarge the class of monotonic algorithms. Within this context, this paper presents a new algorithm that implements a search for a bounded control with given bounds. Numeric...
A branch-and-cut algorithm for the capacitated open vehicle routing problem
DEFF Research Database (Denmark)
Letchford, A.N.; Lysgaard, Jens; Eglese, R.W.
2007-01-01
In open vehicle routing problems, the vehicles are not required to return to the depot after completing service. In this paper, we present the first exact optimization algorithm for the open version of the well-known capacitated vehicle routing problem (CVRP). The algorithm is based on branch...... assess the quality of existing heuristic methods, and to compare the relative difficulty of open and closed versions of the same problem....
A Branch-and-Cut Algorithm for the Capacitated Open Vehicle Routing Problem
DEFF Research Database (Denmark)
Letchford, Adam N.; Lysgaard, Jens; Eglese, Richard W.
In open vehicle routing problems, the vehicles are not required to return to the depot after completing service. In this paper, we present the first exact optimization algorithm for the open version of the well-known capacitated vehicle routing problem (CVRP). The algorithm is based on branch...... assess the quality of existing heuristic methods, and to compare the relative difficulty of open and closed versions of the same problem....
Persistence-Based Branch Misprediction Bounds for WCET Analysis
DEFF Research Database (Denmark)
Puffitsch, Wolfgang
2015-01-01
Branch prediction is an important feature of pipelined processors to achieve high performance. However, it can lead to overly pessimistic worst-case execution time (WCET) bounds when being modeled too conservatively. This paper presents bounds on the number of branch mispredictions for local dyna...... linear programming formulations of the WCET problem. An evaluation on a number of benchmarks shows that with these bounds, dynamic branch prediction does not necessarily lead to higher WCET bounds than static prediction schemes....
Institute of Scientific and Technical Information of China (English)
TongXiaojiao; ZhouShuzi
2003-01-01
This paper presents a trust region two-phase model algorithm for solving the equality and bound constratined nonlinear optimization problem.A concept of substationary point is given.Under sutable assumptions.the global convergence of this algorithm is proved without assuming the linear independence of the gradient of active constraints.A numerical example is also presented.
A Branch-and-Price Algorithm for the Capacitated Arc Routing Problem with Stochastic Demands
DEFF Research Database (Denmark)
Christiansen, Christian Holk; Lysgaard, Jens; Wøhlk, Sanne
2009-01-01
We address the Capacitated Arc Routing Problem with Stochastic Demands (CARPSD), which we formulate as a Set Partitioning Problem. The CARPSD is solved by a Branch-and-Price algorithm, which we apply without graph transformation. The demand's stochastic nature is incorporated into the pricing...
Phylogenies without Branch Bounds: Contracting the Short, Pruning the Deep
Daskalakis, Constantinos; Roch, Sebastien
2008-01-01
We introduce a new phylogenetic reconstruction algorithm which, unlike most previous rigorous inference techniques, does not rely on assumptions regarding the branch lengths or the depth of the tree. The algorithm returns a forest which is guaranteed to contain all edges that are: 1) sufficiently long and 2) sufficiently close to the leaves. How much of the true tree is recovered depends on the sequence length provided. The algorithm is distance-based and runs in polynomial time.
JPLEX: Java Simplex Implementation with Branch-and-Bound Search for Automated Test Assembly
Park, Ryoungsun; Kim, Jiseon; Dodd, Barbara G.; Chung, Hyewon
2011-01-01
JPLEX, short for Java simPLEX, is an automated test assembly (ATA) program. It is a mixed integer linear programming (MILP) solver written in Java. It reads in a configuration file, solves the minimization problem, and produces an output file for postprocessing. It implements the simplex algorithm to create a fully relaxed solution and…
Extension of Welch-Berlekamp theorem and universal strategy of decoding algorithm beyond BCH bound
Institute of Scientific and Technical Information of China (English)
忻鼎稼
1995-01-01
In consideration of decoding cydic codes, a general formula for error pattern prediction is obtained. It extends the Welch-Berlekamp theorem and expands the Welch-Berlekamp algorithm, so that the limitation from BCH bound is broken, and the algorithm turns into a universal one which meets the actual minimum distance as well as complete decoding beyond the minimum distance in the case of decoding BCH codes and general cydic codes.
Parameterized Expectations Algorithm and the Moving Bounds: a comment on convergence properties
Pérez, Javier J.; A. Jesús Sánchez
2005-01-01
In this paper we analyze the convergence properties of the moving bounds algorithm to initialize the Parameterized Expectations Algorithm suggested by Maliar and Maliar (2003) [Journal of Business and Economic Statistics 1, pp. 88-92]. We carry out a Monte Carlo experiment to check its performance against some initialization alternatives based on homotopy principles. We do so within the framework of two standard neoclassical growth models. We show that: (i) speed of convergence is poor as com...
A hybrid of genetic algorithm and Fletcher-Reeves for bound constrained optimization problems
Asoke Kumar Bhunia; Pintu Pal; Samiran Chattopadhyay
2015-01-01
In this paper a hybrid algorithm for solving bound constrained optimization problems having continuously differentiable objective functions using Fletcher Reeves method and advanced Genetic Algorithm (GA) have been proposed. In this approach, GA with advanced operators has been applied for computing the step length in the feasible direction in each iteration of Fletcher Reeves method. Then this idea has been extended to a set of multi-point approximations instead of single point approximation...
Blind Deconvolution Meets Blind Demixing: Algorithms and Performance Bounds
Ling, Shuyang; Strohmer, Thomas
2015-01-01
Consider $r$ sensors, each one intends to send a function $x_i$ (e.g. a signal or image) to a receiver common to all $r$ sensors. Before transmission, each $x_i$ is multiplied by an "encoding matrix" $A_i$. During transmission each $A_ix_i$ gets convolved with a function $h_i$. The receiver records the function $y$, given by the sum of all these convolved signals. Assume that the receiver knowns all the $A_i$, but does neither know the $x_i$ nor the $h_i$. When and under which conditions is i...
Energy Technology Data Exchange (ETDEWEB)
Joseph W. Nielsen; Akira Tokurio; Robert Hiromoto; Jivan Khatry
2014-06-01
Traditional Probabilistic Risk Assessment (PRA) methods have been developed and are quite effective in evaluating risk associated with complex systems, but lack the capability to evaluate complex dynamic systems. These time and energy scales associated with the transient may vary as a function of transition time to a different physical state. Dynamic PRA (DPRA) methods provide a more rigorous analysis of complex dynamic systems, while complete, results in issues associated with combinatorial explosion. In order to address the combinatorial complexity arising from the number of possible state configurations and discretization of transition times, a characteristic scaling metric (LENDIT – length, energy, number, distribution, information and time) is proposed as a means to describe systems uniformly and thus provide means to describe relational constraints expected in the dynamics of a complex (coupled) systems. Thus when LENDIT is used to characterize four sets – ‘state, system, resource and response’ (S2R2) – describing reactor operations (normal and off-normal), LENDIT and S2R2 in combination have the potential to ‘branch and bound’ the state space investigated by DPRA. In this paper we introduce the concept of LENDIT scales and S2R2 sets applied to a branch-and-bound algorithm and apply the methods to a station black out transient (SBO).
The KL-UCB Algorithm for Bounded Stochastic Bandits and Beyond
Garivier, Aurélien
2011-01-01
This paper presents a finite-time analysis of the KL-UCB algorithm, an online, horizon-free index policy for stochastic bandit problems. We prove two distinct results: first, for arbitrary bounded rewards, the KL-UCB algorithm satisfies a uniformly better regret bound than UCB or UCB2; second, in the special case of Bernoulli rewards, it reaches the lower bound of Lai and Robbins. Furthermore, we show that simple adaptations of the KL-UCB algorithm are also optimal for specific classes of (possibly unbounded) rewards, including those generated from exponential families of distributions. A large-scale numerical study comparing KL-UCB with its main competitors (UCB, UCB2, UCB-Tuned, UCB-V, DMED) shows that KL-UCB is remarkably efficient and stable, including for short time horizons. KL-UCB is also the only method that always performs better than the basic UCB policy. Our regret bounds rely on deviations results of independent interest which are stated and proved in the Appendix. As a by-product, we also obtain ...
Frecon, Jordan; Didier, Gustavo; Pustelnik, Nelly; Abry, Patrice
2016-08-01
Self-similarity is widely considered the reference framework for modeling the scaling properties of real-world data. However, most theoretical studies and their practical use have remained univariate. Operator Fractional Brownian Motion (OfBm) was recently proposed as a multivariate model for self-similarity. Yet it has remained seldom used in applications because of serious issues that appear in the joint estimation of its numerous parameters. While the univariate fractional Brownian motion requires the estimation of two parameters only, its mere bivariate extension already involves 7 parameters which are very different in nature. The present contribution proposes a method for the full identification of bivariate OfBm (i.e., the joint estimation of all parameters) through an original formulation as a non-linear wavelet regression coupled with a custom-made Branch & Bound numerical scheme. The estimation performance (consistency and asymptotic normality) is mathematically established and numerically assessed by means of Monte Carlo experiments. The impact of the parameters defining OfBm on the estimation performance as well as the associated computational costs are also thoroughly investigated.
A branch-and-cut-and-price algorithm for the cumulative capacitated vehicle routing problem
DEFF Research Database (Denmark)
Wøhlk, Sanne; Lysgaard, Jens
2014-01-01
The paper considers the Cumulative Capacitated Vehicle Routing Problem (CCVRP), which is a variation of the well-known Capacitated Vehicle Routing Problem (CVRP). In this problem, the traditional objective of minimizing total distance or time traveled by the vehicles is replaced by minimizing the...... the sum of arrival times at the customers. A branch-and-cut-and-price algorithm for obtaining optimal solutions to the problem is proposed. Computational results based on a set of standard CVRP benchmarks are presented.......The paper considers the Cumulative Capacitated Vehicle Routing Problem (CCVRP), which is a variation of the well-known Capacitated Vehicle Routing Problem (CVRP). In this problem, the traditional objective of minimizing total distance or time traveled by the vehicles is replaced by minimizing...
A hybrid of genetic algorithm and Fletcher-Reeves for bound constrained optimization problems
Directory of Open Access Journals (Sweden)
Asoke Kumar Bhunia
2015-04-01
Full Text Available In this paper a hybrid algorithm for solving bound constrained optimization problems having continuously differentiable objective functions using Fletcher Reeves method and advanced Genetic Algorithm (GA have been proposed. In this approach, GA with advanced operators has been applied for computing the step length in the feasible direction in each iteration of Fletcher Reeves method. Then this idea has been extended to a set of multi-point approximations instead of single point approximation to avoid the convergence of the existing method at local optimum and a new method, called population based Fletcher Reeves method, has been proposed to find the global or nearer to global optimum. Finally to study the performance of the proposed method, several multi-dimensional standard test functions having continuous partial derivatives have been solved. The results have been compared with the same of recently developed hybrid algorithm with respect to different comparative factors.
A Branch-and-Price Algorithm for Two Multi-Compartment Vehicle Routing Problems
DEFF Research Database (Denmark)
Mirzaei, Samira; Wøhlk, Sanne
2016-01-01
Despite the vast body of literature on vehicle routing problems, little attention has been paid to multi-compartment vehicle routing problems that investigate transportation of different commodities on the same vehicle, but in different compartments. In this project, we present two strategically...... different versions of the MCVRP in general settings. In the first version, different commodities may be delivered to the customer by different vehicles, but the full amount of each product must be delivered by a single vehicle. In the second version, each customer may only be serviced by a single vehicle......, which must deliver the full amount of all commodities demanded by that customer. We present a Branch-and-Price algorithm for solving the two versions of the problem to optimality and we analyze the effect of the strategic decision of whether or not to allow multiple visits to the same customer...
AnkurPachauriand Gursaran
2012-01-01
In search based test data generation, the problem of test data generation is reduced to that of function minimization or maximization.Traditionally, for branch testing, the problem of test data generation has been formulated as a minimization problem. In this paper we define an alternate maximization formulation and experimentally compare it with the minimization formulation. We use a genetic algorithm as the search technique and in addition to the usual genetic algorithm opera...
Etessami, Kousha; Yannakakis, Mihalis
2012-01-01
We show that one can approximate the least fixed point solution for a multivariate system of monotone probabilistic max(min) polynomial equations, referred to as maxPPSs (and minPPSs, respectively), in time polynomial in both the encoding size of the system of equations and in log(1/epsilon), where epsilon > 0 is the desired additive error bound of the solution. (The model of computation is the standard Turing machine model.) We establish this result using a generalization of Newton's method which applies to maxPPSs and minPPSs, even though the underlying functions are only piecewise-differentiable. This generalizes our recent work which provided a P-time algorithm for purely probabilistic PPSs. These equations form the Bellman optimality equations for several important classes of infinite-state Markov Decision Processes (MDPs). Thus, as a corollary, we obtain the first polynomial time algorithms for computing to within arbitrary desired precision the optimal value vector for several classes of infinite-state...
Comparing branch-and-price algorithms for the Multi-Commodity k-splittable Maximum Flow Problem
DEFF Research Database (Denmark)
Gamst, Mette; Petersen, Bjørn
2012-01-01
The Multi-Commodity k-splittable Maximum Flow Problem consists in routing as much flow as possible through a capacitated network such that each commodity uses at most k paths and the capacities are satisfied. The problem appears in telecommunications, specifically when considering Multi......-Protocol Label Switching. The problem has previously been solved to optimality through branch-and-price. In this paper we propose two exact solution methods both based on an alternative decomposition. The two methods differ in their branching strategy. The first method, which branches on forbidden edge sequences......, shows some performance difficulty due to large search trees. The second method, which branches on forbidden and forced edge sequences, demonstrates much better performance. The latter also outperforms a leading exact solution method from the literature. Furthermore, a heuristic algorithm is presented...
New Algorithms and Lower Bounds for Sequential-Access Data Compression
Gagie, Travis
2009-02-01
This thesis concerns sequential-access data compression, i.e., by algorithms that read the input one or more times from beginning to end. In one chapter we consider adaptive prefix coding, for which we must read the input character by character, outputting each character's self-delimiting codeword before reading the next one. We show how to encode and decode each character in constant worst-case time while producing an encoding whose length is worst-case optimal. In another chapter we consider one-pass compression with memory bounded in terms of the alphabet size and context length, and prove a nearly tight tradeoff between the amount of memory we can use and the quality of the compression we can achieve. In a third chapter we consider compression in the read/write streams model, which allows us passes and memory both polylogarithmic in the size of the input. We first show how to achieve universal compression using only one pass over one stream. We then show that one stream is not sufficient for achieving good grammar-based compression. Finally, we show that two streams are necessary and sufficient for achieving entropy-only bounds.
Bound entanglement and entanglement bounds
Energy Technology Data Exchange (ETDEWEB)
Sauer, Simeon [Physikalisch-Astronomische Fakultaet, Friedrich-Schiller-Univesitaet Jena (Germany)]|[Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder-Strasse 3, D-79104 Freiburg (Germany); Melo, Fernando de; Mintert, Florian; Buchleitner, Andreas [Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder-Strasse 3, D-79104 Freiburg (Germany)]|[Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str.38, D-01187 Dresden (Germany); Bae, Joonwoo [School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-012 (Korea); Hiesmayr, Beatrix [Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna (Austria)
2008-07-01
We investigate the separability of Bell-diagonal states of two qutrits. By using lower bounds to algebraically estimate concurrence, we find convex regions of bound entangled states. Some of these regions exactly coincide with the obtained results when employing optimal entanglement witnesses, what shows that the lower bound can serve as a precise detector of entanglement. Some hitherto unknown regions of bound entangled states were discovered with this approach, and delimited efficiently.
Refined Error Bounds for Several Learning Algorithms
Hanneke, Steve
2015-01-01
This article studies the achievable guarantees on the error rates of certain learning algorithms, with particular focus on refining logarithmic factors. Many of the results are based on a general technique for obtaining bounds on the error rates of sample-consistent classifiers with monotonic error regions, in the realizable case. We prove bounds of this type expressed in terms of either the VC dimension or the sample compression size. This general technique also enables us to derive several ...
Zhou, YuQian
2012-01-01
This paper proposes a method to find efficient bounded algorithms of NPC problems by machine enumeration. The key contributions are: * On Universal Turing Machines, a program's time complexity should be characterized as: execution time(n) = loading time(n) + running time(n). * Introduces the concept of bounded algorithms; proposes a comparison based criterion to decide if a bounded algorithm is inefficient; and establishes the length upper bound of efficient bounded programs. * Introduces a new way to evaluate program complexity by using the growth rate characteristic function, which is more easily machine checkable based on observations.
The RHMC algorithm for theories with unknown spectral bounds
Kogut, J B
2006-01-01
The Rational Hybrid Monte Carlo (RHMC) algorithm extends the Hybrid Monte Carlo algorithm for lattice QCD simulations to situations involving fractional powers of the determinant of the quadratic Dirac operator. This avoids the updating increment ($dt$) dependence of observables which plagues the Hybrid Molecular-dynamics (HMD) method. The RHMC algorithm uses rational approximations to fractional powers of the quadratic Dirac operator. Such approximations are only available when positive upper and lower bounds to the operator's spectrum are known. We apply the RHMC algorithm to simulations of 2 theories for which a positive lower spectral bound is unknown: lattice QCD with staggered quarks at finite isospin chemical potential and lattice QCD with massless staggered quarks and chiral 4-fermion interactions ($\\chi$QCD). A choice of lower bound is made in each case, and the properties of the RHMC simulations these define are studied. Justification of our choices of lower bounds is made by comparing measurements ...
New physics upper bound on the branching ratio of B_s--> l+ l- and B_s--> l+ l- gamma
Alok, A K; Alok, Ashutosh Kumar
2007-01-01
We consider the most general new physics effective Lagrangian for b--> s l+ l-. We derive the upper limit on the branching ratio for the processes B_s--> l^+ l- where l=e, mu, subject to the current experimental bounds on related processes, B--> (K,K*) l+ l-. If the new physics interactions are of vector/axial-vector form, the present measured rates for B--> (K,K*) l+ l- constrain B_s--> l+ l to be of the same order of magnitude as their respective Standard Model (SM) predictions. On the other hand, if the new physics interactions are of scalar/pseudoscalar form, B--> (K,K*) l+ l- rates do not impose any useful constraint on B_s--> l+ l- and the branching ratios of these decays can be as large as present experimental upper bounds. If future experiments measure B_s--> l+ l- to be > 10^{-8} then the new physics giving rise to these decays has to be of the scalar/pseudoscalar form. We also consider the effect of new physics on B_s--> l+ l- gamma subject to the present experimental constraints on B--> (K,K*) l+ l...
Algorithms for Quantum Branching Programs Based on Fingerprinting
Directory of Open Access Journals (Sweden)
Farid Ablayev
2009-11-01
Full Text Available In the paper we develop a method for constructing quantum algorithms for computing Boolean functions by quantum ordered read-once branching programs (quantum OBDDs. Our method is based on fingerprinting technique and representation of Boolean functions by their characteristic polynomials. We use circuit notation for branching programs for desired algorithms presentation. For several known functions our approach provides optimal QOBDDs. Namely we consider such functions as Equality, Palindrome, and Permutation Matrix Test. We also propose a generalization of our method and apply it to the Boolean variant of the Hidden Subgroup Problem.
Algorithms for Quantum Branching Programs Based on Fingerprinting
Ablayev, Farid; 10.4204/EPTCS.9.1
2009-01-01
In the paper we develop a method for constructing quantum algorithms for computing Boolean functions by quantum ordered read-once branching programs (quantum OBDDs). Our method is based on fingerprinting technique and representation of Boolean functions by their characteristic polynomials. We use circuit notation for branching programs for desired algorithms presentation. For several known functions our approach provides optimal QOBDDs. Namely we consider such functions as Equality, Palindrome, and Permutation Matrix Test. We also propose a generalization of our method and apply it to the Boolean variant of the Hidden Subgroup Problem.
New physics upper bound on the branching ratio of B_s --> l+ l-
Alok, A K; Alok, Ashutosh Kumar
2005-01-01
We consider new physics interactions for b --> s l+ l- of the form vector/axial-vector. We derive the upper limit on the branching ratio for the processes B_s --> l+ l-, where l=e or mu, subject to the current experimental bounds on related processes, B --> K l+ l- and B --> K* l+ l-. We obtain 3 sigma upper bounds B(B_s --> e+ e-) mu+ mu-) < 5*10^(-9).
Çağlar, F; Ozbek, I Y
2012-01-01
Heart sound localization in chest sound is an essential part for many heart sound cancellation algorithms. The main difficulty for heart sound localization methods is the precise determination of the onset and offset boundaries of the heart sound segment. This paper presents a novel method to estimate lower and upper bounds for the onset and offset of the heart sound segment, which can be used as anchor points for more precise estimation. For this purpose, first chest sound is divided into frames and then entropy and smoothed entropy features of these frames are extracted, and used in the Convex-hull algorithm to estimate the upper and lower bounds for heart sound boundaries. The Convex-hull algorithm constructs a special type of envelope function for entropy features and if the maximal difference between the envelope function and the entropy is larger than a certain threshold, this point is considered as a heart sound bound. The results of the proposed method are compared with a baseline method which is a modified version of a well-known heart sound localization method. The results show that the proposed method outperforms the baseline method in terms of accuracy and detection error rate. Also, the experimental results show that smoothing entropy features significantly improves the performance of both baseline and proposed methods. PMID:23366867
Cramér-Rao Bounds and Estimation Algorithms for Delay/Doppler and Conventional Altimetry
Halimi, Abderrahim; Mailhes, Corinne; Tourneret, J. -Y.
2013-01-01
International audience Delay/Doppler radar altimetry has been receiving an increasing interest, especially since the launch of the first altimeter in 2010. It aims at reducing the measurement noise and increasing the along-track resolution in comparison with conventional pulse limited altimetry. A semi-analytical model was recently introduced for this new generation of delay/Doppler altimeters. The first contribution of this paper is the derivation of the Cramér-Rao bounds (CRBs) associat...
A branch-and-price algorithm for the capacitated vehicle routing problem with stochastic demands
DEFF Research Database (Denmark)
Christiansen, Christian Holk; Lysgaard, Jens
2007-01-01
This article introduces a new exact algorithm for the Capacitated Vehicle Routing Problem with Stochastic Demands (CVRPSD). The CVRPSD can be formulated as a Set Partitioning Problem and it is shown that the associated column generation subproblem can be solved using a dynamic programming scheme...
Nghia, Nguyen Duc; Binh, Huynh Thi Thanh
2008-01-01
We have introduced the heuristic algorithm for solving BDMST problem, called CBRC. The experiment shows that CBRC have best result than the other known heuristic algorithm for solving BDMST prolem on Euclidean instances. The best solution found by the genetic algorithm which uses best heuristic algorithm or only one heuristic algorithm for initialization the population is not better than the best solution found by the genetic algorithm which uses mixed heuristic algorithms (randomized heurist...
A branch-and-cut algorithm for the capacitated profitable tour problem
DEFF Research Database (Denmark)
Jepsen, Mads Kehlet; Petersen, Bjørn; Spoorendonk, Simon;
2014-01-01
This paper considers the Capacitated Profitable Tour Problem (CPTP) which is a special case of the Elementary Shortest Path Problem with Resource Constraints (ESPPRC). The CPTP belongs to the group of problems known as traveling salesman problems with profits. In CPTP each customer is associated...... with a profit and a demand and the objective is to find a capacitated tour (rooted in a depot node) that minimizes the total travel distance minus the profit of the visited customers. The CPTP can be recognized as the sub-problem in many column generation applications, where it is traditionally solved through...... dynamic programming. In this paper we present an alternative framework based on a formulation for the undirected CPTP and solved through branch-and-cut. Valid inequalities are presented among which we introduce a new family of inequalities for the CPTP denoted rounded multistar inequalities and we prove...
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...
Ait moussa, Abdellah; Jassemnejad, Bahaeddin
2014-05-01
Nanocomposites with high-aspect ratio fillers attract enormous attention because of the superior physical properties of the composite over the parent matrix. Nanocomposites with functionalized graphene as fillers did not produce the high thermal conductivity expected due to the high interfacial thermal resistance between the functional groups and graphene flakes. We report here a robust and efficient technique that identifies the configuration of the functionalities for improved thermal conductivity. The method combines linearization of the interatomic interactions, calculation, and optimization of the thermal conductivity using the globalized and bounded Nelder-Mead algorithm.
A branch-and-price algorithm for the long-term home care scheduling problem
DEFF Research Database (Denmark)
Gamst, Mette; Jensen, Thomas Sejr
2012-01-01
In several countries, home care is provided for certain citizens living at home. The long-term home care scheduling problem is to generate work plans such that a high quality of service is maintained, the work hours of the employees are respected, and the overall cost is kept as low as possible. We...... propose a branchand-price algorithm for the long-term home care scheduling problem. The pricing problem generates a one-day plan for an employee, and the master problem merges the plans with respect to regularity constraints. The method is capable of generating plans with up to 44 visits during one week....
Directory of Open Access Journals (Sweden)
Hadi Mokhtari
2013-01-01
Full Text Available In this paper, the problem of received order scheduling by a manufacturer, with the measure of maximum completion times of orders, has been formulated and then an analytical approach has been devised for its solution. At the beginning of a planning period, the manufacturer receives a number of orders from customers, each of which requires two different stages for processing. In order to minimize the work in process inventories, the no-wait condition between two operations of each order is regarded. Then, the equality of obtained schedules is proved by machine idle time minimization, as objective, with the schedules obtained by maximum completion time minimization. A concept entitled “Order pairing” has been defined and an algorithm for achieving optimal order pairs which is based on symmetric assignment problem has been presented. Using the established order pairs, an upper bound has been developed based on contribution of every order pair out of total machines idle time. Out of different states of improving upper bound, 12 potential situations of order pairs sequencing have been also evaluated and then the upper bound improvement has been proved in each situation, separately. Finally, a heuristic algorithm has been developed based on attained results of pair improvement and a case study in printing industry has been investigated and analyzed to approve its applicability.
Energy Technology Data Exchange (ETDEWEB)
Boutin, D.
2005-08-01
The first experimental observation of bound-state beta-decay showed, that due solely to the electron stripping, a stable nuclide, e.g. {sup 163}Dy, became unstable. Also a drastic modification of the half-life of bare {sup 187}Re, from 4.12(2) x 10{sup 10} years down to 32.9(20) years, could be observed. It was mainly due to the possibility for the mother nuclide to decay into a previously inaccessible nuclear level of the daughter nuclide. It was proposed to study a nuclide where this decay mode was competing with continuum-state beta-decay, in order to measure their respective branchings. The ratio {beta}{sub b}/{beta}{sub c} could also be evaluated for the first time. {sup 207}Tl was chosen due to its high atomic number, and Q-value of about 1.4 MeV, small enough to enhance the {beta}{sub b} probability and large enough to allow the use of time-resolved Schottky Mass Spectrometry (SMS) to study the evolution of mother and bound-state beta-decay daughter ions. The decay properties of the ground state and isomeric state of {sup 207}Tl{sup 81+} have been investigated at the GSI accelerator facility in two separate experiments. For the first time {beta}-decay where the electron could go either to a bound state (atomic orbitals) and lead to {sup 207}Pb{sup 81+} as a daughter nuclide, or to a continuum state and lead to {sup 207}Pb{sup 82+}, has been observed. The respective branchings of these two processes could be measured as well. The deduced total nuclear half-life of 255(17) s for {sup 207}Tl{sup 81+}, was slightly modified with respect to the half-life of the neutral atom of 286(2) s. It was nevertheless in very good agreement with calculations based on the assumption that the beta-decay was following an allowed type of transition. The branching {beta}{sub b}/{beta}{sub c}=0.192(20), was also in very good agreement with the same calculations. The application of stochastic precooling allowed to observe in addition the 1348 keV short-lived isomeric state of {sup
Artigues, Christian; Gendreau, Michel; Rousseau, Louis-Martin; Vergnaud, Adrien
2009-01-01
We propose exact hybrid methods based on integer linear programming and constraint programming for an integrated employee timetabling and job-shop scheduling problem. Each method we investigate uses a constraint programming (CP) formulation associated with a linear programming (LP) relaxation. Under a CP framework, the LP-relaxation is integrated into a global constraint using in addition reduced cost-based filtering techniques. We propose two CP formulations of the problem yielding two diffe...
Improved branch and bound algorithm for detecting SNP-SNP interactions in breast cancer
Chuang, Li-Yeh; Chang, Hsueh-Wei; Lin, Ming-Cheng; Yang, Cheng-Hong
2013-01-01
Background Single nucleotide polymorphisms (SNPs) in genes derived from distinct pathways are associated with a breast cancer risk. Identifying possible SNP-SNP interactions in genome-wide case–control studies is an important task when investigating genetic factors that influence common complex traits; the effects of SNP-SNP interaction need to be characterized. Furthermore, observations of the complex interplay (interactions) between SNPs for high-dimensional combinations are still computati...
Tracking Infection Diffusion in Social Networks: Filtering Algorithms and Threshold Bounds
Krishnamurthy, Vikram; Pedersen, Tavis
2016-01-01
This paper deals with the statistical signal pro- cessing over graphs for tracking infection diffusion in social networks. Infection (or Information) diffusion is modeled using the Susceptible-Infected-Susceptible (SIS) model. Mean field approximation is employed to approximate the discrete valued infected degree distribution evolution by a deterministic ordinary differential equation for obtaining a generative model for the infection diffusion. The infected degree distribution is shown to follow polynomial dynamics and is estimated using an exact non- linear Bayesian filter. We compute posterior Cramer-Rao bounds to obtain the fundamental limits of the filter which depend on the structure of the network. Considering the time-varying nature of the real world networks, the relationship between the diffusion thresholds and the degree distribution is investigated using generative models for real world networks. In addition, we validate the efficacy of our method with the diffusion data from a real-world online s...
Institute of Scientific and Technical Information of China (English)
LIU Xiao; WANG Cheng-en
2005-01-01
This paper addresses a single item dynamic lot-sizing model with inventory capacity and out-sourcing. The goal is to minimize the total costs of production, setup, inventory holding and out-sourcing. Two versions of an out-sourcing model with time-varying costs are considered: stock out case and conservation case. Zero Inventory Order property has been found and some new properties are obtained in an optimal solution. Dynamic programming algorithms are developed to solve the problem in strongly polynomial time respectively. Furthermore, some numerical results demonstrate that the approach proposed is efficient and applicable.
BOUNDING PYRAMIDS AND BOUNDING CONES FOR TRIANGULAR BEZIER SURFACES
Institute of Scientific and Technical Information of China (English)
Jian-song Deng; Fa-lai Chen; Li-li Wang
2000-01-01
This paper describes practical approaches on how to construct bounding pyramids and bounding cones for triangular Bézier surfaces. Examples are provided to illustrate the process of construction and comparison is made between various surface bounding volumes. Furthermore, as a starting point for the construction,we provide a way to compute hodographs of triangular Bézier surfaces and improve the algorithm for computing the bounding cone of a set of vectors.
New physics upper bound on the branching ratio of B_s--> l+ l- and B_s--> l+ l- gamma
Alok, Ashutosh Kumar; Sankar, S. Uma
2006-01-01
We consider the most general new physics effective Lagrangian for b--> s l+ l-. We derive the upper limit on the branching ratio for the processes B_s--> l^+ l- where l=e, mu, subject to the current experimental bounds on related processes, B--> (K,K*) l+ l-. If the new physics interactions are of vector/axial-vector form, the present measured rates for B--> (K,K*) l+ l- constrain B_s--> l+ l to be of the same order of magnitude as their respective Standard Model (SM) predictions. On the othe...
Directory of Open Access Journals (Sweden)
Bisheng He
2014-01-01
Full Text Available A time-space network based optimization method is designed for high-speed rail train timetabling problem to improve the service level of the high-speed rail. The general time-space path cost is presented which considers both the train travel time and the high-speed rail operation requirements: (1 service frequency requirement; (2 stopping plan adjustment; and (3 priority of train types. Train timetabling problem based on time-space path aims to minimize the total general time-space path cost of all trains. An improved branch-and-price algorithm is applied to solve the large scale integer programming problem. When dealing with the algorithm, a rapid branching and node selection for branch-and-price tree and a heuristic train time-space path generation for column generation are adopted to speed up the algorithm computation time. The computational results of a set of experiments on China’s high-speed rail system are presented with the discussions about the model validation, the effectiveness of the general time-space path cost, and the improved branch-and-price algorithm.
Formulations and Branch-and-Cut Algorithms for the Generalized Vehicle Routing Problem
DEFF Research Database (Denmark)
Bektas, Tolga; Erdogan, Günes; Røpke, Stefan
2011-01-01
The Generalized Vehicle Routing Problem (GVRP) consists of nding a set of routes for a number of vehicles with limited capacities on a graph with the vertices partitioned into clusters with given demands such that the total cost of travel is minimized and all demands are met. This paper offers four...
Kohei Arai
2012-01-01
Method for visualization of URL link structure and URL retrievals using internal structure of URLs based on brunch and bound method is proposed. Twisting link structure of URLs can be solved by the proposed visualization method. Also some improvements are observed for the proposed brunch and bound based method in comparison to the conventional URL retrieval methods.
A Branch and Cut algorithm for the container shipping network design problem
DEFF Research Database (Denmark)
Reinhardt, Line Blander; Kallehauge, Brian; Pisinger, David
The network design problem in liner shipping is of increasing importance in a strongly competitive market where potential cost reductions can influence market share and profits significantly. In this paper the network design and fleet assignment problems are combined into a mixed integer linear...
A Branch and Cut algorithm for the container shipping network design problem
DEFF Research Database (Denmark)
Reinhardt, Line Blander; Pisinger, David
2012-01-01
The network design problem in liner shipping is of increasing importance in a strongly competitive market where potential cost reductions can influence market share and profits significantly. In this paper the network design and fleet assignment problems are combined into a mixed integer linear...
Improved Bounds on Quantum Learning Algorithms
Atici, A; Atici, Alp; Servedio, Rocco A.
2004-01-01
In this article we give several new results on the complexity of algorithms that learn Boolean functions from quantum queries and quantum examples. Hunziker et al. conjectured that for any class C of Boolean functions, the number of quantum black-box queries which are required to exactly identify an unknown function from C is at most $O(\\frac{\\log |C|}{\\sqrt{{\\hat{\\gamma}}^{C}}})$, where $\\hat{\\gamma}^{C}$ is a combinatorial parameter of the class C. We essentially resolve this conjecture in the affirmative by giving a quantum algorithm that, for any class C, identifies any unknown function from C using at most $O(\\frac{\\log |C| \\log \\log |C|}{\\sqrt{{\\hat{\\gamma}}^{C}}})$ quantum black-box queries. We consider a range of natural problems intermediate between the exact learning problem (in which the learner must obtain all bits of information about the black-box function) and the usual problem of computing a predicate (in which the learner must obtain only one bit of information about the black-box function). ...
New physics upper bound on the branching ratio of B_s --> l+ l-
Alok, Ashutosh Kumar; Sankar, S. Uma
2005-01-01
We consider the most general new physics effective Lagrangian for b --> s l+ l-. We derive the upper limit on the branching ratio for the processes B_s --> l+ l- where l=e, mu, subject to the current experimental bounds on related processes, B --> K l+ l- and B --> K* l+ l-. If the new physics interactions are of vector/axial-vector form, the present measured rates for B --> (K,K*) l+ l- constrain B(B_s --> l+ l-) to be of the same order of magnitude as their respective Standard Model predict...
R. Freling (Richard); R.M. Lentink (Ramon); A.P.M. Wagelmans (Albert)
2001-01-01
textabstractThis paper discusses a decision support system for airline and railway crew planning. The system is a state-of-the-art branch-and-price solver that is used for crew scheduling and crew rostering. We briefly discuss the mathematical background of the solver, of which most part is covered
Directory of Open Access Journals (Sweden)
Dinesh Gupta
2012-03-01
Full Text Available Various sheduling algorithm are available forthe operating system to improve CPU utilization.Different scheduling algorithms have differentproperties that work on different schedulingcriterias and the choice of a particular algorithmmay favor one class of processes over another.SJF gives minimum average waiting time for agiven set of processes. The Round Robinalgorithm decreases the response time. In thispaper we have proposed an algorithm which hasresponse time aproximately zero and itincreases the efficiency of I/O boundedprocess.
Freling, Richard; Lentink, Ramon; Wagelmans, Albert
2001-01-01
textabstractThis paper discusses a decision support system for airline and railway crew planning. The system is a state-of-the-art branch-and-price solver that is used for crew scheduling and crew rostering. We briefly discuss the mathematical background of the solver, of which most part is covered in the Operations Research literature. Crew scheduling is crew planning for one or a few days that results in crew duties or pairings, and crew rostering is crew planning for at least one week for ...
DEFF Research Database (Denmark)
Robenek, Tomáš; Umang, Nitish; Bierlaire, Michel;
2014-01-01
In this research, two crucial optimization problems of berth allocation and yard assignment in the context of bulk ports are studied. We discuss how these problems are interrelated and can be combined and solved as a single large scale optimization problem. More importantly we highlight the diffe......In this research, two crucial optimization problems of berth allocation and yard assignment in the context of bulk ports are studied. We discuss how these problems are interrelated and can be combined and solved as a single large scale optimization problem. More importantly we highlight......-shaking neighborhood search is presented. The proposed algorithms are tested and validated through numerical experiments based on instances inspired from real bulk port data. The results indicate that the algorithms can be successfully used to solve instances containing up to 40 vessels within reasonable computational...
Koenigs function and branching processes
Chikilev, O G
2001-01-01
An explicit solution of time-homogeneous pure birth branching processes is described. It gives alternative extensions for the negative binomial distribution (branching processes with immigration) and for the Furry-Yule distribution (branching processes without immigration).
Branch-pipe-routing approach for ships using improved genetic algorithm
Sui, Haiteng; Niu, Wentie
2016-09-01
Branch-pipe routing plays fundamental and critical roles in ship-pipe design. The branch-pipe-routing problem is a complex combinatorial optimization problem and is thus difficult to solve when depending only on human experts. A modified genetic-algorithm-based approach is proposed in this paper to solve this problem. The simplified layout space is first divided into threedimensional (3D) grids to build its mathematical model. Branch pipes in layout space are regarded as a combination of several two-point pipes, and the pipe route between two connection points is generated using an improved maze algorithm. The coding of branch pipes is then defined, and the genetic operators are devised, especially the complete crossover strategy that greatly accelerates the convergence speed. Finally, simulation tests demonstrate the performance of proposed method.
Branch-pipe-routing approach for ships using improved genetic algorithm
Sui, Haiteng; Niu, Wentie
2016-05-01
Branch-pipe routing plays fundamental and critical roles in ship-pipe design. The branch-pipe-routing problem is a complex combinatorial optimization problem and is thus difficult to solve when depending only on human experts. A modified genetic-algorithm-based approach is proposed in this paper to solve this problem. The simplified layout space is first divided into threedimensional (3D) grids to build its mathematical model. Branch pipes in layout space are regarded as a combination of several two-point pipes, and the pipe route between two connection points is generated using an improved maze algorithm. The coding of branch pipes is then defined, and the genetic operators are devised, especially the complete crossover strategy that greatly accelerates the convergence speed. Finally, simulation tests demonstrate the performance of proposed method.
A tighter bound for the self-stabilization time in Hermanʼs algorithm
DEFF Research Database (Denmark)
Feng, Yuan; Zhang, Lijun
2013-01-01
We study the expected self-stabilization time of Hermanʼs algorithm. For N processors the lower bound is 427N2 (0.148N2), and an upper bound of 0.64N2 is presented in Kiefer et al. (2011) [4]. In this paper we give a tighter upper bound 0.521N2. © 2013 Published by Elsevier B.V.......We study the expected self-stabilization time of Hermanʼs algorithm. For N processors the lower bound is 427N2 (0.148N2), and an upper bound of 0.64N2 is presented in Kiefer et al. (2011) [4]. In this paper we give a tighter upper bound 0.521N2. © 2013 Published by Elsevier B.V....
Automated test data generation for branch testing using incremental genetic algorithm
Indian Academy of Sciences (India)
T MANIKUMAR; A JOHN SANJEEV KUMAR; R MARUTHAMUTHU
2016-09-01
Cost of software testing can be reduced by automated test data generation to find a minimal set of data that has maximum coverage. Search-based software testing (SBST) is one of the techniques recently used for automated testing task. SBST makes use of control flow graph (CFG) and meta-heuristic search algorithms to accomplish the process. This paper focuses on test data generation for branch coverage. A major drawback in using meta-heuristic techniques is that the CFG paths have to be traversed from the starting node to end node for each automated test data. This kind of traversal could be improved by branch ordering, together with elitism. But still the population size and the number of iterations are maintained as the same to keep all the branches alive. In this paper, we present an incremental genetic algorithm (IGA) for branch coverage testing. Initially, a classical genetic algorithm (GA) is used to construct the population with the best parents for each branch node, and the IGA is started with these parents as the initial population. Hence, it is not necessary to maintain a huge population size and large number of iterations to cover all the branches. The performance is analyzed with five benchmark programs studied from the literature. The experimental results indicate that the proposed IGA search technique outperforms the other meta-heuristic search techniques in terms of memory usage and scalability.
A New Method for Lower Bounds on the Running Time of Evolutionary Algorithms
Sudholt, Dirk
2011-01-01
We present a new method for proving lower bounds on the expected running time of evolutionary algorithms. It is based on fitness-level partitions and an additional condition on transition probabilities between fitness levels. The method is versatile, intuitive, elegant, and very powerful. It yields exact or near-exact lower bounds for LO, OneMax, long k-paths, and all functions with a unique optimum. Most lower bounds are very general: they hold for all evolutionary algorithms that only use b...
Exponential Lower Bounds for the PPSZ k-SAT Algorithm
DEFF Research Database (Denmark)
Chen, Shiteng; Scheder, Dominik Alban; Talebanfard, Navid;
2013-01-01
In 1998, Paturi, Pudl´ak, Saks, and Zane presented PPSZ, an elegant randomized algorithm for k-SAT. Fourteen years on, this algorithm is still the fastest known worst-case algorithm. They proved that its expected running time on k-CNF formulas with n variables is at most 2(1−k)n, where k 2 (1/k...
Institute of Scientific and Technical Information of China (English)
童小娇; 周叔子
2003-01-01
This paper presents a trust region two-phase model algorithm for solving the equality and bound constrained nonlinear optimization problem. A concept of substationary point is given. Under suitable assumptions,the global convergence of this algorithm is proved without assuming the linear independence of the gradient of active constraints. A numerical example is also presented.
Quiver Varieties and Branching
Directory of Open Access Journals (Sweden)
Hiraku Nakajima
2009-01-01
Full Text Available Braverman and Finkelberg recently proposed the geometric Satake correspondence for the affine Kac-Moody group Gaff [Braverman A., Finkelberg M., arXiv:0711.2083]. They conjecture that intersection cohomology sheaves on the Uhlenbeck compactification of the framed moduli space of Gcpt-instantons on $R^4/Z_r$ correspond to weight spaces of representations of the Langlands dual group $G_{aff}^{vee}$ at level $r$. When $G = SL(l$, the Uhlenbeck compactification is the quiver variety of type $sl(r_{aff}$, and their conjecture follows from the author's earlier result and I. Frenkel's level-rank duality. They further introduce a convolution diagram which conjecturally gives the tensor product multiplicity [Braverman A., Finkelberg M., Private communication, 2008]. In this paper, we develop the theory for the branching in quiver varieties and check this conjecture for $G = SL(l$.
Methods and Technologies Branch (MTB)
The Methods and Technologies Branch focuses on methods to address epidemiologic data collection, study design and analysis, and to modify technological approaches to better understand cancer susceptibility.
An Individual Tree Detection Algorithm for Dense Deciduous Forests with Spreading Branches
Shao, G.
2015-12-01
Individual tree information derived from LiDAR may have the potential to assist forest inventory and improve the assessment of forest structure and composition for sustainable forest management. The algorithms developed for individual tree detection are commonly focusing on finding tree tops to allocation the tree positions. However, the spreading branches (cylinder crowns) in deciduous forests cause such kind of algorithms work less effectively on dense canopy. This research applies a machine learning algorithm, mean shift, to position individual trees based on the density of LiDAR point could instead of detecting tree tops. The study site locates in a dense oak forest in Indiana, US. The selection of mean shift kernels is discussed. The constant and dynamic bandwidths of mean shit algorithms are applied and compared.
Path-valued branching processes and nonlocal branching superprocesses
Li, Zenghu
2012-01-01
A family of continuous-state branching processes with immigration are constructed as the solution flow of a stochastic equation system driven by time-space noises. The family can be regarded as an inhomogeneous increasing path-valued branching process with immigration. Two nonlocal branching immigration superprocesses can be defined from the flow. We identify explicitly the branching and immigration mechanisms of those processes. The results provide new perspectives into the tree-valued Markov processes of Aldous and Pitman [Ann. Inst. H. Poincare Probab. Statist. 34 (1998), 637--686] and Abraham and Delmas [Ann. Probab. To appear].
Joint MAP bias estimation and data association: algorithms
Danford, Scott; Kragel, Bret; Poore, Aubrey
2007-09-01
The problem of joint maximum a posteriori (MAP) bias estimation and data association belongs to a class of nonconvex mixed integer nonlinear programming problems. These problems are difficult to solve due to both the combinatorial nature of the problem and the nonconvexity of the objective function or constraints. A specific problem that has received some attention in the tracking literature is that of the target object map problem in which one tries match a set of tracks as observed by two different sensors in the presence of biases, which are modeled here as a translation between the track states. The general framework also applies to problems in which the costs are general nonlinear functions of the biases. The goal of this paper is to present a class of algorithms based on the branch and bound framework and the "all-pairs" and k-best heuristics that provide a good initial upper bound for a branch and bound algorithm. These heuristics can be used as part of a real-time algorithm or as part of an "anytime algorithm" within the branch and bound framework. In addition, we consider both the A*-search and depth-first search procedures as well as several efficiency improvements such as gating. While this paper focuses on the algorithms, a second paper will focus on simulations.
Institute of Scientific and Technical Information of China (English)
LIU Chang-he; SHANG You-lin; LI Zhen-guo
2015-01-01
We establish polynomial complexity bounds of the Mehrotra-type predictor-corrector algorithms for linear programming over symmetric cones. We first slightly modify the maximum step size in the predictor step of the safeguard based Mehrotra-type algorithm for linear programming, that was proposed by Salahi et al[18]. Then, using the machinery of Euclidean Jordan algebras, we extend the modified algorithm to symmetric cones. Based on the Nesterov-Todd direction, we obtain O(r logε−1) iteration complexity bound of this algorithm, where r is the rank of the Jordan algebras andεis the required precision. We also present a new variant of Mehrotra-type algorithm using a new adaptive updating scheme of centering parameter and show that this algorithm enjoys the same order of complexity bound as the safeguard algorithm. We illustrate the numerical behaviour of the methods on some small examples.
Subexponential lower bounds for randomized pivoting rules for the simplex algorithm
DEFF Research Database (Denmark)
Friedmann, Oliver; Hansen, Thomas Dueholm; Zwick, Uri
2011-01-01
The simplex algorithm is among the most widely used algorithms for solving linear programs in practice. With essentially all deterministic pivoting rules it is known, however, to require an exponential number of steps to solve some linear programs. No non-polynomial lower bounds were known, prior...... to this work, for randomized pivoting rules. We provide the first subexponential (i.e., of the form 2Ω(nα), for some α>0) lower bounds for the two most natural, and most studied, randomized pivoting rules suggested to date. The first randomized pivoting rule considered is Random-Edge, which among all...... improving pivoting steps (or edges) from the current basic feasible solution (or vertex) chooses one uniformly at random. The second randomized pivoting rule considered is Random-Facet, a more complicated randomized pivoting rule suggested by Kalai and by Matousek, Sharir and Welzl. Our lower bound for the...
Institute of Scientific and Technical Information of China (English)
Chunxia Jia; Detong Zhu
2008-01-01
In this paper we propose an affine scaling interior algorithm via conjugate gradient path for solving nonlinear equality systems subject to bounds on variables.By employing the affine scaling conjugate gradient path search strategy,we obtain an iterative direction by solving the linearize model.By using the line search technique,we will find an acceptable trial step length along this direction which is strictly feasible and makes the objective function nonmonotonically decreasing.The global convergence and fast local convergence rate of the proposed algorithm are established under some reasonable conditions.Furthermore,the numerical results of the proposed algorithm indicate to be effective.
Analysis of imbalanced weather data based on branch-and-bound approach%基于分支限界的不平衡气象数据晴雨分析
Institute of Scientific and Technical Information of China (English)
王剑辉; 梁路; 王彪
2016-01-01
This paper proposed the modified cost-sensitive learning methods to preprocess the imbalance weather data.Con-sidering about the specialty of weather data,it made the value of rainfall per unit time as the cost value.So the data could be divided into two types of rain and non-rain effectively and reasonably.And then it used logic-based approach to analysie the data processed,used branch-and-bound approach to derive a Boolean classifier.Experimental results show that this method is feasible and effective.What’s more,it’s valid to perform any further logic calculation or logic operation on the result of the Boolean classifiers,achieving more flexibility.%提出基于修改的代价敏感学习的方法对不平衡的天气数据进行预处理，结合天气数据自身的特点，以单位时间的降雨量为成本的值，将数据合理有效地区分为下雨和非下雨两类；进而运用基于逻辑的方法对处理完的数据进行分析，运用分支限界算法得出布尔分类器。实验结果表明此方法可行有效，该方法可进一步对布尔分类器结果进行逻辑运算，从而达到更加灵活的操作分类器的效果。
An Improved Lower Bound Limit State Optimisation Algorithm
DEFF Research Database (Denmark)
Frier, Christian; Damkilde, Lars
2010-01-01
Limit State analysis has been used in engineering practice for many years e.g. the yield-line method for concrete slabs and slip-line solutions in geotechnics. In the recent years there has been an increased interest in numerical Limit State analysis, and today algorithms take into account the non...
International Nuclear Information System (INIS)
The presence of weakly bound rotationally excited initial states of HD2+ lying just below the lowest dissociation limit has been observed as well as quasi-bound, predissociative final states above the dissociation limit resulting from one-photon excitation of those weakly bound states. The excitation of the initial weakly bound and possibly only few quasi-bound states took place with 1064 nm laser radiation. The possibility of one-photon excitation of the vibrationally excited initial HD2+ ions is considered. The centre-of-mass kinetic energy distributions of the D+ and H+ fragment were used to identify the possible initial and final states involved in the transitions leading to these fragments. The fragment ratio D+/H+ is shown to be critically dependent on the ion source pressure. A strong preference is observed for the D++HD dissociation channel over the H++D2 channel at high source gas pressures. The centre-of-mass energy of the resulting H+ and D+ fragments was found to agree with predicted theoretical values, and suggest that among initially excited HD2+ ions, only a few of these lie initially above the lowest dissociation limit. (author)
Energy Technology Data Exchange (ETDEWEB)
Yousif, F.B. [Centro de Ciencias Fisicas, UNAM, Cuernavaca, Morelos (Mexico)]. E-mail: fbyousif@fis.unam.mx; Cisneros, C.; Urquijo, J. de; Alvarez, I. [Centro de Ciencias Fisicas, UNAM, Cuernavaca, Morelos (Mexico)
2001-03-14
The presence of weakly bound rotationally excited initial states of HD{sub 2}{sup +} lying just below the lowest dissociation limit has been observed as well as quasi-bound, predissociative final states above the dissociation limit resulting from one-photon excitation of those weakly bound states. The excitation of the initial weakly bound and possibly only few quasi-bound states took place with 1064 nm laser radiation. The possibility of one-photon excitation of the vibrationally excited initial HD{sub 2}{sup +} ions is considered. The centre-of-mass kinetic energy distributions of the D{sup +} and H{sup +} fragment were used to identify the possible initial and final states involved in the transitions leading to these fragments. The fragment ratio D{sup +}/H{sup +} is shown to be critically dependent on the ion source pressure. A strong preference is observed for the D{sup +}+HD dissociation channel over the H{sup +}+D{sub 2} channel at high source gas pressures. The centre-of-mass energy of the resulting H{sup +} and D{sup +} fragments was found to agree with predicted theoretical values, and suggest that among initially excited HD{sub 2}{sup +} ions, only a few of these lie initially above the lowest dissociation limit. (author)
Lan, Fujun; Bayraksan, Güzin; Lansey, Kevin
2016-03-01
A regional water supply system design problem that determines pipe and pump design parameters and water flows over a multi-year planning horizon is considered. A non-convex nonlinear model is formulated and solved by a branch-and-reduce global optimization approach. The lower bounding problem is constructed via a three-pronged effort that involves transforming the space of certain decision variables, polyhedral outer approximations, and the Reformulation Linearization Technique (RLT). Range reduction techniques are employed systematically to speed up convergence. Computational results demonstrate the efficiency of the proposed algorithm; in particular, the critical role range reduction techniques could play in RLT based branch-and-bound methods. Results also indicate using reclaimed water not only saves freshwater sources but is also a cost-effective non-potable water source in arid regions. Supplemental data for this article can be accessed at http://dx.doi.org/10.1080/0305215X.2015.1016508.
Cryptographic protocol security analysis based on bounded constructing algorithm
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
An efficient approach to analyzing cryptographic protocols is to develop automatic analysis tools based on formal methods. However, the approach has encountered the high computational complexity problem due to reasons that participants of protocols are arbitrary, their message structures are complex and their executions are concurrent. We propose an efficient automatic verifying algorithm for analyzing cryptographic protocols based on the Cryptographic Protocol Algebra (CPA) model proposed recently, in which algebraic techniques are used to simplify the description of cryptographic protocols and their executions. Redundant states generated in the analysis processes are much reduced by introducing a new algebraic technique called Universal Polynomial Equation and the algorithm can be used to verify the correctness of protocols in the infinite states space. We have implemented an efficient automatic analysis tool for cryptographic protocols, called ACT-SPA, based on this algorithm, and used the tool to check more than 20 cryptographic protocols. The analysis results show that this tool is more efficient, and an attack instance not offered previously is checked by using this tool.
EXACT ALGORITHM FOR BIN COVERING
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
This paper presents a new arc flow model for the one-dimensional bin covering problem and an algorithm to solve the problem exactly through a branch-and-bound procedure and the technique of column generation. The subproblems occuring in the procedure of branch-and-bound have the same structure and therefore can be solved by the same algorithm. In order to solve effectively the subproblems which are generally large scale, a column generation algorithm is employed. Many rules found in this paper can improve the performance of the methods.
Daskalova, Nina
2010-01-01
Multitype branching processes (MTBP) model branching structures, where the nodes of the resulting tree are particles of different types. Usually such a process is not observable in the sense of the whole tree, but only as the “generation” at a given moment in time, which consists of the number of particles of every type. This requires an EM-type algorithm to obtain a maximum likelihood (ML) estimate of the parameters of the branching process. Using a version of the inside-outside ...
A Finite Continuation Algorithm for Bound Constrained Quadratic Programming
DEFF Research Database (Denmark)
Madsen, Kaj; Nielsen, Hans Bruun; Pinar, Mustafa C.
1999-01-01
The dual of the strictly convex quadratic programming problem with unit bounds is posed as a linear $\\ell_1$ minimization problem with quadratic terms. A smooth approximation to the linear $\\ell_1$ function is used to obtain a parametric family of piecewise-quadratic approximation problems...
An efficient algorithm for upper bound on the partition function of nucleic acids.
Chitsaz, Hamidreza; Forouzmand, Elmirasadat; Haffari, Gholamreza
2013-07-01
It has been shown that minimum free-energy structure for RNAs and RNA-RNA interaction is often incorrect due to inaccuracies in the energy parameters and inherent limitations of the energy model. In contrast, ensemble-based quantities such as melting temperature and equilibrium concentrations can be more reliably predicted. Even structure prediction by sampling from the ensemble and clustering those structures by Sfold has proven to be more reliable than minimum free energy structure prediction. The main obstacle for ensemble-based approaches is the computational complexity of the partition function and base-pairing probabilities. For instance, the space complexity of the partition function for RNA-RNA interaction is O(n4) and the time complexity is O(n6), which is prohibitively large. Our goal in this article is to present a fast algorithm, based on sparse folding, to calculate an upper bound on the partition function. Our work is based on the recent algorithm of Hazan and Jaakkola (2012). The space complexity of our algorithm is the same as that of sparse folding algorithms, and the time complexity of our algorithm is O(MFE(n)ℓ) for single RNA and O(MFE(m, n)ℓ) for RNA-RNA interaction in practice, in which MFE is the running time of sparse folding and ℓ≤n (ℓ≤n+m) is a sequence-dependent parameter.
Energy Technology Data Exchange (ETDEWEB)
Bechtle, Philip [Bonn Univ. (Germany). Physikalisches Inst.; Heinemeyer, Sven [Instituto de Fisica de Cantabria (CSIC-UC), Santander (Spain); Staal, Oscar [Stockholm Univ. (Sweden). Dept. of Physics; Stefaniak, Tim; Williams, Karina E. [Bonn Univ. (Germany). Physikalisches Inst.; Bonn Univ. (Germany). Bethe Center for Theoretical Physics; Weiglein, Georg [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Brein, Oliver
2013-12-15
We describe the new developments in version 4 of the public computer code HiggsBounds. HiggsBounds is a tool to test models with arbitrary Higgs sectors, containing both neutral and charged Higgs bosons, against the published exclusion bounds from Higgs searches at the LEP, Tevatron and LHC experiments. From the model predictions for the Higgs masses, branching ratios, production cross sections and total decay widths - which are specified by the user in the input for the program - the code calculates the predicted signal rates for the search channels considered in the experimental data. The signal rates are compared to the expected and observed cross section limits from the Higgs searches to determine whether a point in the model parameter space is excluded at 95% confidence level. In this paper we present a modification of the HiggsBounds main algorithm that extends the exclusion test in order to ensure that it provides useful results in the presence of one or more significant excesses in the data, corresponding to potential Higgs signals. We also describe a new method to test whether the limits from an experimental search performed under certain model assumptions can be applied to a different theoretical model. Further developments discussed here include a framework to take into account theoretical uncertainties on the Higgs mass predictions, and the possibility to obtain the {chi}{sup 2} likelihood of Higgs exclusion limits from LEP. Extensions to the user subroutines from earlier versions of HiggsBounds are described. The new features are demonstrated by additional example programs.
Step Size Bound of the Sequential Partial Update LMS Algorithm with Periodic Input Signals
Directory of Open Access Journals (Sweden)
Pedro Ramos
2006-12-01
Full Text Available This paper derives an upper bound for the step size of the sequential partial update (PU LMS adaptive algorithm when the input signal is a periodic reference consisting of several harmonics. The maximum step size is expressed in terms of the gain in step size of the PU algorithm, defined as the ratio between the upper bounds that ensure convergence in the following two cases: firstly, when only a subset of the weights of the filter is updated during every iteration; and secondly, when the whole filter is updated at every cycle. Thus, this gain in step-size determines the factor by which the step size parameter can be increased in order to compensate the inherently slower convergence rate of the sequential PU adaptive algorithm. The theoretical analysis of the strategy developed in this paper excludes the use of certain frequencies corresponding to notches that appear in the gain in step size. This strategy has been successfully applied in the active control of periodic disturbances consisting of several harmonics, so as to reduce the computational complexity of the control system without either slowing down the convergence rate or increasing the residual error. Simulated and experimental results confirm the expected behavior.
Branching processes and neutral evolution
Taïb, Ziad
1992-01-01
The Galton-Watson branching process has its roots in the problem of extinction of family names which was given a precise formulation by F. Galton as problem 4001 in the Educational Times (17, 1873). In 1875, an attempt to solve this problem was made by H. W. Watson but as it turned out, his conclusion was incorrect. Half a century later, R. A. Fisher made use of the Galton-Watson process to determine the extinction probability of the progeny of a mutant gene. However, it was J. B. S. Haldane who finally gave the first sketch of the correct conclusion. J. B. S. Haldane also predicted that mathematical genetics might some day develop into a "respectable branch of applied mathematics" (quoted in M. Kimura & T. Ohta, Theoretical Aspects of Population Genetics. Princeton, 1971). Since the time of Fisher and Haldane, the two fields of branching processes and mathematical genetics have attained a high degree of sophistication but in different directions. This monograph is a first attempt to apply the current sta...
Z. Degraeve (Zeger); R.F. Jans (Raf)
2007-01-01
textabstractAlthough the textbook Dantzig-Wolfe decomposition reformulation for the capacitated lot-sizing problem, as already proposed by Manne [Manne, A. S. 1958. Programming of economic lot sizes. Management Sci. 4(2) 115-135], provides a strong lower bound, it also has an important structural de
New physics upper bound on the branching ratio of B_s --> l+ l- gamma
Alok, A K; Alok, Ashutosh Kumar
2006-01-01
We consider the effect of new physics on the branching ratio of B_s --> l+ l- gamma where l = e, mu. If the new physics is of the form scalar/pseudoscalar, then it makes no contribution to B_s --> l+ l- gamma, unlike in the case of B_s --> l+ l-, where it can potentially make a very large contribution. New Physics in the form of vector/axial-vector operators cannot lead to large enhancement of B_s --> l+ l- gamma much beyond the Standard Model expectation. But new physics in the form of tensor/pseudo-tensor operators can.
New physics upper bound on the branching ratio of B_s --> l+ l- gamma
Alok, Ashutosh Kumar; Sankar, S. Uma
2006-01-01
We consider the effect of new physics on the branching ratio of B_s--> l+ l- gamma where l=e,mu. If the new physics is of the form scalar/pseudoscalar, then it makes no contribution to B_s--> l+ l- gamma, unlike in the case of B_s--> l+ l-, where it can potentially make a very large contribution. If the new physics is in the form of vector/axial-vector operators, then present data on B-->(K,K^*)l+ l-, does not allow a large enhancement for B_s--> l+ l- gamma. If the new physics is in the form...
A Note on Multitype Branching Process with Bounded Immigration in Random Environment
Institute of Scientific and Technical Information of China (English)
Hua Ming WANG
2013-01-01
In this paper,we study the total number of progeny,W,before regenerating of multitype branching process with immigration in random environment.We show that the tail probability of |W| is of order t-κ as t → ∞,with κ some constant.As an application,we prove a stable law for (L-1) random walk in random environment,generalizing the stable law for the nearest random walk in random environment (see "Kesten,Kozlov,Spitzer:A limit law for random walk in a random environment.Compositio Math.,30,145-168 (1975)").
Directory of Open Access Journals (Sweden)
Matsen Frederick A
2012-05-01
Full Text Available Abstract Background Although taxonomy is often used informally to evaluate the results of phylogenetic inference and the root of phylogenetic trees, algorithmic methods to do so are lacking. Results In this paper we formalize these procedures and develop algorithms to solve the relevant problems. In particular, we introduce a new algorithm that solves a "subcoloring" problem to express the difference between a taxonomy and a phylogeny at a given rank. This algorithm improves upon the current best algorithm in terms of asymptotic complexity for the parameter regime of interest; we also describe a branch-and-bound algorithm that saves orders of magnitude in computation on real data sets. We also develop a formalism and an algorithm for rooting phylogenetic trees according to a taxonomy. Conclusions The algorithms in this paper, and the associated freely-available software, will help biologists better use and understand taxonomically labeled phylogenetic trees.
Weekly Fleet Assignment Model and Algorithm
Institute of Scientific and Technical Information of China (English)
ZHU Xing-hui; ZHU Jin-fu; GONG Zai-wu
2007-01-01
A 0-1 integer programming model for weekly fleet assignment was put forward based on linear network and weekly flight scheduling in China. In this model, the objective function is to maximize the total profit of fleet assignment, subject to the constraints of coverage, aircraft flow balance, fleet size, aircraft availability, aircraft usage, flight restriction, aircraft seat capacity,and stopover. Then the branch-and-bound algorithm based on special ordered set was applied to solve the model. At last, a realworld case study on an airline with 5 fleets, 48 aircrafts and 1 786 flight legs indicated that the profit increase was $1591276 one week and the running time was no more than 4 min, which shows that the model and algorithm are fairly good for domestic airline.
Electron propagator calculations on linear and branched carbon cluster dianions
Energy Technology Data Exchange (ETDEWEB)
Zakrzewski, V.G.; Ortiz, J.V. [Univ. of New Mexico, Albuquerque, NM (United States)
1994-12-31
Electron propagator calculations have been performed on linear carbon cluster dianions from C{sub 7}{sup 2-} to C{sub 10}{sup 2-} and on branched C{sub 7}{sup 2-}, C{sub 9}{sup 2-} and C{sub 11}{sup 2-} structures which have a central, tricoordinate carbon bound to three branches with alternating long and short bonds. The more stable, branched isomer of C{sub 7}{sup 2-} has a positive vertical ionization energy, but the linear form does not. While linear C{sub 10}{sup 2-} is stable with respect to electron loss, it is not possible to decide from these calculations whether linear C{sub 8}{sup 2-} and C{sub 9}{sup 2-} have the same property. There is evidence that better calculations would obtain bound C{sub 8}{sup 2-} and C{sub 9}{sup 2-} species. All branched dianions have positive, vertical ionization energies. Feynman-Dyson amplitudes for dianion ionization energies display delocalized {pi} bonding, with the two terminal carbons of the longest branches making the largest contributions.
Bounded Densities and Their Derivatives
DEFF Research Database (Denmark)
Kozine, Igor; Krymsky, V.
2009-01-01
This paper describes how one can compute interval-valued statistical measures given limited information about the underlying distribution. The particular focus is on a bounded derivative of a probability density function and its combination with other available statistical evidence for computing...
Stochastic Transition between Turbulent Branch and Thermodynamic Branch of an Inhomogeneous Plasma
Kawasaki, Mitsuhiro; Itoh, Sanae-I.; Yagi, Masatoshi; Itoh, Kimitaka
2002-01-01
Transition phenomena between thermodynamic branch and turbulent branch in submarginal turbulent plasma are analyzed with statistical theory. Time-development of turbulent fluctuation is obtained by numerical simulations of Langevin equation which contains submarginal characteristics. Probability density functions and transition rates between two states are analyzed. Transition from turbulent branch to thermodynamic branch occurs in almost entire region between subcritical bifurcation point an...
Clinical and Translational Epidemiology Branch (CTEB)
The Clinical and Translational Epidemiology Branch focuses on factors that influence cancer progression, recurrence, survival, and other treatment outcomes, and factors associated with cancer development.
Can the Adaptive Metropolis Algorithm Collapse Without the Covariance Lower Bound?
Vihola, Matti
2009-01-01
The Adaptive Metropolis (AM) algorithm is based on the symmetric random-walk Metropolis algorithm. The proposal distribution has the following time-dependent covariance matrix at step $n+1$ \\[ S_n = Cov(X_1,...,X_n) + \\epsilon I, \\] that is, the sample covariance matrix of the history of the chain plus a (small) constant $\\epsilon>0$ multiple of the identity matrix $I$. The lower bound on the eigenvalues of $S_n$ induced by the factor $\\epsilon I$ is theoretically convenient, but practically cumbersome, as a good value for the parameter $\\epsilon$ may not always be easy to choose. This article considers variants of the AM algorithm that do not explicitly bound the eigenvalues of $S_n$ away from zero. The behaviour of $S_n$ is studied in detail, indicating that the eigenvalues of $S_n$ do not tend to collapse to zero in general.
Algorithmic complexity and entanglement of quantum states.
Mora, Caterina E; Briegel, Hans J
2005-11-11
We define the algorithmic complexity of a quantum state relative to a given precision parameter, and give upper bounds for various examples of states. We also establish a connection between the entanglement of a quantum state and its algorithmic complexity.
Meyer, Ulrich; Negoescu, Andrei; Weichert, Volker
Despite disillusioning worst-case behavior, classic algorithms for single-source shortest-paths (SSSP) like Bellman-Ford are still being used in practice, especially due to their simple data structures. However, surprisingly little is known about the average-case complexity of these approaches. We provide new theoretical and experimental results for the performance of classic label-correcting SSSP algorithms on graph classes with non-negative random edge weights. In particular, we prove a tight lower bound of Ω(n 2) for the running times of Bellman-Ford on a class of sparse graphs with O(n) nodes and edges; the best previous bound was Ω(n 4/3 - ɛ ). The same improvements are shown for Pallottino's algorithm. We also lift a lower bound for the approximate bucket implementation of Dijkstra's algorithm from Ω(n logn / loglogn) to Ω(n 1.2 - ɛ ). Furthermore, we provide an experimental evaluation of our new graph classes in comparison with previously used test inputs.
Recursion relations and branching rules for simple Lie algebras
Lyakhovsky, V D
1995-01-01
The branching rules between simple Lie algebras and its regular (maximal) simple subalgebras are studied. Two types of recursion relations for anomalous relative multiplicities are obtained. One of them is proved to be the factorized version of the other. The factorization property is based on the existence of the set of weights \\Gamma specific for each injection. The structure of \\Gamma is easily deduced from the correspondence between the root systems of algebra and subalgebra. The recursion relations thus obtained give rise to simple and effective algorithm for branching rules. The details are exposed by performing the explicit decomposition procedure for A_{3} \\oplus u(1) \\rightarrow B_{4} injection.
2013-03-26
... Agency Information Collection Activities; Comment Request; Upward Bound and Upward Bound Math Science... Upward Bound Math Science Annual Performance Report. OMB Control Number: 1840-NEW. Type of Review: New... under the regular Upward Bound (UB) and Upward Bound Math and Science (UBMS) Programs. The Department...
An Improved Chaotic Bat Algorithm for Solving Integer Programming Problems
Directory of Open Access Journals (Sweden)
Osama Abdel Raouf
2014-08-01
Full Text Available Bat Algorithm is a recently-developed method in the field of computational intelligence. In this paper is presented an improved version of a Bat Meta-heuristic Algorithm, (IBACH, for solving integer programming problems. The proposed algorithm uses chaotic behaviour to generate a candidate solution in behaviors similar to acoustic monophony. Numerical results show that the IBACH is able to obtain the optimal results in comparison to traditional methods (branch and bound, particle swarm optimization algorithm (PSO, standard Bat algorithm and other harmony search algorithms. However, the benefits of this proposed algorithm is in its ability to obtain the optimal solution within less computation, which save time in comparison with the branch and bound algorithm (exact solution method.
Cellular and physical mechanisms of branching morphogenesis
Varner, Victor D.; Nelson, Celeste M.
2014-01-01
Branching morphogenesis is the developmental program that builds the ramified epithelial trees of various organs, including the airways of the lung, the collecting ducts of the kidney, and the ducts of the mammary and salivary glands. Even though the final geometries of epithelial trees are distinct, the molecular signaling pathways that control branching morphogenesis appear to be conserved across organs and species. However, despite this molecular homology, recent advances in cell lineage analysis and real-time imaging have uncovered surprising differences in the mechanisms that build these diverse tissues. Here, we review these studies and discuss the cellular and physical mechanisms that can contribute to branching morphogenesis. PMID:25005470
Pen Branch Delta and Savannah River Swamp Hydraulic Model
International Nuclear Information System (INIS)
The proposed Savannah River Site (SRS) Wetlands Restoration Project area is located in Barnwell County, South Carolina on the southwestern boundary of the SRS Reservation. The swamp covers about 40.5 km2 and is bounded to the west and south by the Savannah River and to the north and east by low bluffs at the edge of the Savannah River floodplain. Water levels within the swamp are determined by stage along the Savannah River, local drainage, groundwater seepage, and inflows from four tributaries, Beaver Dam Creek, Fourmile Branch, Pen Branch, and Steel Creek. Historic discharges of heated process water into these tributaries scoured the streambed, created deltas in the adjacent wetland, and killed native vegetation in the vicinity of the delta deposits. Future releases from these tributaries will be substantially smaller and closer to ambient temperatures. One component of the proposed restoration project will be to reestablish indigenous wetland vegetation on the Pen Branch delta that covers about 1.0 km2. Long-term predictions of water levels within the swamp are required to determine the characteristics of suitable plants. The objective of the study was to predict water levels at various locations within the proposed SRS Wetlands Restoration Project area for a range of Savannah River flows and regulated releases from Pen Branch. TABS-MD, a United States Army Corps of Engineer developed two-dimensional finite element open channel hydraulic computer code, was used to model the SRS swamp area for various flow conditions
Pen Branch Delta and Savannah River Swamp Hydraulic Model
Energy Technology Data Exchange (ETDEWEB)
Chen, K.F.
1999-05-13
The proposed Savannah River Site (SRS) Wetlands Restoration Project area is located in Barnwell County, South Carolina on the southwestern boundary of the SRS Reservation. The swamp covers about 40.5 km2 and is bounded to the west and south by the Savannah River and to the north and east by low bluffs at the edge of the Savannah River floodplain. Water levels within the swamp are determined by stage along the Savannah River, local drainage, groundwater seepage, and inflows from four tributaries, Beaver Dam Creek, Fourmile Branch, Pen Branch, and Steel Creek. Historic discharges of heated process water into these tributaries scoured the streambed, created deltas in the adjacent wetland, and killed native vegetation in the vicinity of the delta deposits. Future releases from these tributaries will be substantially smaller and closer to ambient temperatures. One component of the proposed restoration project will be to reestablish indigenous wetland vegetation on the Pen Branch delta that covers about 1.0 km2. Long-term predictions of water levels within the swamp are required to determine the characteristics of suitable plants. The objective of the study was to predict water levels at various locations within the proposed SRS Wetlands Restoration Project area for a range of Savannah River flows and regulated releases from Pen Branch. TABS-MD, a United States Army Corps of Engineer developed two-dimensional finite element open channel hydraulic computer code, was used to model the SRS swamp area for various flow conditions.
Stellar Evolution Bounds on the ALP-Photon Coupling: new Results and Perspectives
Giannotti, Maurizio
2014-01-01
Stellar evolution considerations are of fundamental importance in our understanding of the axion/ALP-photon coupling, g_{a\\gamma}. Helium burning stars are the best laboratories to study this coupling. Here, we will review the bounds from massive and low mass helium burning stars, and present a new analysis of the bound from the horizontal branch stars. The analysis provides the strongest bound to date on g_{a\\gamma} in a wide mass range.
Sharp Bounds by Probability-Generating Functions and Variable Drift
DEFF Research Database (Denmark)
Doerr, Benjamin; Fouz, Mahmoud; Witt, Carsten
2011-01-01
We introduce to the runtime analysis of evolutionary algorithms two powerful techniques: probability-generating functions and variable drift analysis. They are shown to provide a clean framework for proving sharp upper and lower bounds. As an application, we improve the results by Doerr et al...
Osada, Noriyuki; Takeda, Hiroshi
2003-01-01
To investigate crown development patterns, branch architecture, branch-level light interception, and leaf and branch dynamics were studied in saplings of a plagiotropically branching tree species, Polyalthia jenkinsii Hk. f. & Thoms. (Annonaceae) in a Malaysian rain forest. Lengths of branches and parts of the branches lacking leaves ('bare' branches) were smaller in upper branches than in lower branches within crowns, whereas lengths of 'leafy' parts and the number of leaves per branch were larger in intermediate than in upper and lower branches. Maximum diffuse light absorption (DLA) of individual leaves was not related to sapling height or branch position within crowns, whereas minimum DLA was lower in tall saplings. Accordingly, branch-level light interception was higher in intermediate than in upper and lower branches. The leaf production rate was higher and leaf loss rate was smaller in upper than in intermediate and lower branches. Moreover, the branch production rate of new first-order branches was larger in the upper crowns. Thus, leaf and branch dynamics do not correspond to branch-level light interception in the different canopy zones. As a result of architectural constraints, branches at different vertical positions experience predictable light microenvironments in plagiotropic species. Accordingly, this pattern of carbon allocation among branches might be particularly important for growth and crown development in plagiotropic species. PMID:12495920
Bounded rationality and learning in market competition
Tuinstra, J.; Hommes, C.H.; Kopányi, D.
2015-01-01
This thesis promotes the use of bounded rationality in economic models. The assumption of perfect rationality often imposes high informational and computational burden on economic agents and predictions based on this assumption are not in line with observed behavior in some cases. Models of bounded rationality may better explain actual behavior in such situations. In the thesis we consider market models where firms are boundedly rational: they do not know the demand for their product and they...
Ter-Sarkisov, Aram
2012-01-01
In this article we derive upper bounds on optimization time of the recombination algorithm solving a unimodal problem with plateaus of fitness using a tool we called Elitism Levels Traverse Mechanism. Our findings are asymptotically tight for different parameters of the algorithm and the problem, and we are able to recover some well-known bounds for test problems such as OneMax and Royal Roads. We also present find- ings on the limiting distribution of super-elite species in the population, something no-one seems to have done before in the EA community.
Logic, planning agency and branching time
Directory of Open Access Journals (Sweden)
Ricardo Souza Silvestre
2010-12-01
Full Text Available The purpose of this paper is to give a formal account of a kind of agency so far neglected in the field of philosophical modal logic of action: planning agency. In doing this we follow the standard approach of modal logics of agency exemplified by the works of Belnap, Chellas and Pörn. Since we believe there is a close relation between planning, time and indeterminism, we use the theory of branching time as a conceptual framework for investigating the basic features of planning agency. Besides introducing a branching-time semantics, we also provide a calculus sound and complete with respect to this semantics.
Branching Processes with Immigration and Related Topics
Institute of Scientific and Technical Information of China (English)
LI Zeng-hu
2006-01-01
This is a survey on the recent progresses in the study of branching processes with immigration,generalized Ornstein-Uhlenbeck processes,and affine Markov processes.We mainly focus on the applications of skew convolution semigroups and the connections in those processes.
A subexponential lower bound for the Random Facet algorithm for Parity Games
DEFF Research Database (Denmark)
Friedmann, Oliver; Hansen, Thomas Dueholm; Zwick, Uri
2011-01-01
of turn-based Stochastic Mean Payoff Games. It is a major open problem whether these game families can be solved in polynomial time. The currently theoretically fastest algorithms for the solution of all these games are adaptations of the randomized algorithms of Kalai and of Matouˇsek, Sharir and Welzl......Parity Games form an intriguing family of infinite duration games whose solution is equivalent to the solution of important problems in automatic verification and automata theory. They also form a very natural subclass of Deterministic Mean Payoff Games, which in turn is a very natural subclass...... for LP-type problems, an abstract generalization of linear programming. The expected running time of both algorithms is subexponential in the size of the game, i.e., 2O(√n log n), where n is the number of vertices in the game. We focus in this paper on the algorithm of Matouˇsek, Sharir and Welzl...
Lower Bounds and Semi On-line Multiprocessor Scheduling
Directory of Open Access Journals (Sweden)
T.C. Edwin Cheng
2003-10-01
Full Text Available We are given a set of identical machines and a sequence of jobs from which we know the sum of the job weights in advance. The jobs have to be assigned on-line to one of the machines and the objective is to minimize the makespan. An algorithm with performance ratio 1.6 and a lower bound of 1.5 is presented. This improves recent results by Azar and Regev who published an algorithm with performance ratio 1.625 for the less general problem that the optimal makespan is known in advance.
Vulnerable Derivatives and Good Deal Bounds
DEFF Research Database (Denmark)
Murgoci, Agatha
2013-01-01
a new restriction in the arbitrage free model by setting upper bounds on the Sharpe ratios (SRs) of the assets. The potential prices that are eliminated represent unreasonably good deals. The constraint on the SR translates into a constraint on the stochastic discount factor. Thus, tight pricing bounds...... can be obtained. We provide a link between the objective probability measure and the range of potential risk-neutral measures, which has an intuitive economic meaning. We also provide tight pricing bounds for European calls and show how to extend the call formula to pricing other financial products...
Verifying Resource Bounds of Programs with Lazy Evaluation and Memoization
Madhavan, Ravichandhran; Kuncak, Viktor
2016-01-01
We present a new approach for specifying and verifying resource utilization of functional programs that use lazy evaluation and memoization. Our approach verifies asymptotically tight bounds of complex programs that rely on deep sharing and aliasing of lazy heap references, as well as algorithms that use memoization extensively. Our approach can also find counter-examples for incorrect specifications or implementations. We demonstrate the effectiveness of the approach by verifying the resou...
Branch Retinal Vein Occlusion and Its Management
Institute of Scientific and Technical Information of China (English)
Desmond; Archer
1992-01-01
The natural course of Branch Retinal Vein Occlusion is determined by the site and completeness of the occlusion, the integrity of arterial perfusion to the affected sector and the efficiency of the developing collateral circulation. Most patients with tributary vein occlusion have some capillary fall out and microvascular incompetence in the distribution of the affected retina and vision is significantly compromised in over 50% of patients who have either chronic macular oedema or ischemia involving the...
3rd Workshop on Branching Processes and their Applications
González, Miguel; Gutiérrez, Cristina; Martínez, Rodrigo; Minuesa, Carmen; Molina, Manuel; Mota, Manuel; Ramos, Alfonso; WBPA15
2016-01-01
This volume gathers papers originally presented at the 3rd Workshop on Branching Processes and their Applications (WBPA15), which was held from 7 to 10 April 2015 in Badajoz, Spain (http://branching.unex.es/wbpa15/index.htm). The papers address a broad range of theoretical and practical aspects of branching process theory. Further, they amply demonstrate that the theoretical research in this area remains vital and topical, as well as the relevance of branching concepts in the development of theoretical approaches to solving new problems in applied fields such as Epidemiology, Biology, Genetics, and, of course, Population Dynamics. The topics covered can broadly be classified into the following areas: 1. Coalescent Branching Processes 2. Branching Random Walks 3. Population Growth Models in Varying and Random Environments 4. Size/Density/Resource-Dependent Branching Models 5. Age-Dependent Branching Models 6. Special Branching Models 7. Applications in Epidemiology 8. Applications in Biology and Genetics Offer...
Graphs and matroids weighted in a bounded incline algebra.
Lu, Ling-Xia; Zhang, Bei
2014-01-01
Firstly, for a graph weighted in a bounded incline algebra (or called a dioid), a longest path problem (LPP, for short) is presented, which can be considered the uniform approach to the famous shortest path problem, the widest path problem, and the most reliable path problem. The solutions for LPP and related algorithms are given. Secondly, for a matroid weighted in a linear matroid, the maximum independent set problem is studied.
Kinetics of the Formation and Dissociation of Actin Filament Branches Mediated by Arp2/3 Complex
Mahaffy, Rachel E.; Pollard, Thomas D.
2006-01-01
The actin filament network at the leading edge of motile cells relies on localized branching by Arp2/3 complex from “mother” filaments growing near the plasma membrane. The nucleotide bound to the mother filaments (ATP, ADP and phosphate, or ADP) may influence the branch dynamics. To determine the effect of the nucleotide bound to the subunits of the mother filament on the formation and stability of branches, we compared the time courses of actin polymerization in bulk samples measured using ...
Mutually Unbiased Bases and Bound Entanglement
Hiesmayr, Beatrix C.; Löffler, Wolfgang
2013-01-01
In this contribution we relate two different key concepts: mutually unbiased bases (MUBs) and entanglement; in particular we focus on bound entanglement, i.e. highly mixed states which cannot be distilled by local operations and classical communications. For a certain class of states --for which the state-space forms a "magic" simplex-- we analyze the set of bound entangled states detected by the MUB criterion for different dimensions d and number of particles n. We find that the geometry is ...
[Geometry and algebra of branches of the middle cerebral artery].
Blinkov, S M
1986-01-01
A classification of the cortical branches of the middle cerebral artery (MCA) is suggested by means of which each branch in any hemisphere can be qualified and identified in any variant of MCA branching. The principle of the classification consists in grouping the branches into arteries and trunks of the second, third, etc. order. Branches supplying blood to a certain sector of the lateral surface of the hemisphere are designated arteries. Their number and zone of branching are constant. Branches giving rise to 2 and more arteries are named trunks. Branching of the trunks, the number of trunks of the second, third, etc. order, and the site and type of origin of the arteries are extremely variable. Each trunk can be designated by a formula stating its order and the name of the artery supplied by this trunk. The arrangement of the MCA branches on the surface of the gyri and deep in the sulci, represented on the map of the lateral surface of the hemisphere, is designated conditionally as geometry of MCA branches. The order of branching of the trunks and the type of origin of the arteries, represented on abstract maps of the lateral surface of the hemisphere, are designated conditionally as algebra of the MCA branches. The variability of the geometry and algebra of the MCA branches must be taken into consideration in operations for extra-intracranial microanastomosis and in endovasal intervention on the MCA. PMID:3811741
Trial and Error: A new Approach to Space-Bounded Learning
DEFF Research Database (Denmark)
Ameur, F.; Fischer, Paul; Hoeffgen, H.-U.;
1996-01-01
A pac-learning algorithm is d-space bounded, if it stores at most d examples from the sample at any time. We characterize the d-space learnable concept classes. For this purpose we introduce the compression parameter of a concept class 𝒞 and design our trial and error learning algorithm. We...... show: 𝒞 is d-space learnable if and only if the compression parameter of 𝒞 is at most d. This learning algorithm does not produce a hypothesis consistent with the whole sample as previous approaches, for example, by Floyd, who presents consistent space bounded learning algorithms, but has to...
Li, X Y; Yang, G W; Zheng, D S; Guo, W S; Hung, W N N
2015-01-01
Genetic regulatory networks are the key to understanding biochemical systems. One condition of the genetic regulatory network under different living environments can be modeled as a synchronous Boolean network. The attractors of these Boolean networks will help biologists to identify determinant and stable factors. Existing methods identify attractors based on a random initial state or the entire state simultaneously. They cannot identify the fixed length attractors directly. The complexity of including time increases exponentially with respect to the attractor number and length of attractors. This study used the bounded model checking to quickly locate fixed length attractors. Based on the SAT solver, we propose a new algorithm for efficiently computing the fixed length attractors, which is more suitable for large Boolean networks and numerous attractors' networks. After comparison using the tool BooleNet, empirical experiments involving biochemical systems demonstrated the feasibility and efficiency of our approach.
Lower and Upper Bounds in Zone-Based Abstractions of Timed Automata
DEFF Research Database (Denmark)
Behrmann, Gerd; Bouyer, Patricia; Larsen, Kim Guldstrand;
2005-01-01
be obtained. We show soundness and completeness of the new abstractions w.r.t. reachability and demonstrate how information about lower and upper bounds can be used to optimise the algorithm for bringing a difference bound matrix into normal form. Finally, we experimentally demonstrate that the new techniques...
Lower and Upper Bounds in Zone-Based Abstractions of Timed Automata
DEFF Research Database (Denmark)
Behrmann, Gerd; Bouyer, P.; Larsen, Kim Guldstrand;
2005-01-01
, significantly coarser abstractions can be obtained. We show soundness and completeness of the new abstractions w.r.t. reachability. We demonstrate how information about lower and upper bounds can be used to optimise the algorithm for bringing a difference bound matrix into normal form. Finally, we...
Organization and targets of the European Branch
Energy Technology Data Exchange (ETDEWEB)
Cataldi, R.
1997-12-01
After a short historical review of the formation, objectives and organization of the International Geothermal Association (IGA), this paper describes the functions, goals and activities of the IGA European Branch. In particular, the paper illustrates the plan of action established for the periods 1993-`95 and 1996-`98, and the issues dealt with by the European Forum as of August 1996. The last section of the paper outlines the main problems to be faced in the near future in order to facilitate the aggregation of efforts, the amalgamation of promotional initiatives and the coordination of the basic activities needed for the consolidation and growth of the geothermal community in Europe. (orig.)
40 CFR 721.10094 - Decene, branched and linear.
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Decene, branched and linear. 721.10094... Substances § 721.10094 Decene, branched and linear. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as decene, branched and linear (PMN P-03-272;...
A Forward Reachability Algorithm for Bounded Timed-Arc Petri Nets
DEFF Research Database (Denmark)
David, Alexandre; Jacobsen, Lasse; Jacobsen, Morten;
2012-01-01
the presence of monotonicity-breaking features like age invariants and inhibitor arcs. We implement the algorithm within the model-checkerTAPAAL and the experimental results document an encouraging performance compared to verification approaches that translate TAPN models to UPPAAL timed automata....
HiggsBounds: Confronting arbitrary Higgs sectors with exclusion bounds from LEP and the Tevatron
Bechtle, P.; Brein, O.; Heinemeyer, S.; Weiglein, G.; Williams, K. E.
2010-01-01
HiggsBounds is a computer code that tests theoretical predictions of models with arbitrary Higgs sectors against the exclusion bounds obtained from the Higgs searches at LEP and the Tevatron. The included experimental information comprises exclusion bounds at 95% C.L. on topological cross sections. In order to determine which search topology has the highest exclusion power, the program also includes, for each topology, information from the experiments on the expected exclusion bound, which would have been observed in case of a pure background distribution. Using the predictions of the desired model provided by the user as input, HiggsBounds determines the most sensitive channel and tests whether the considered parameter point is excluded at the 95% C.L. HiggsBounds is available as a Fortran 77 and Fortran 90 code. The code can be invoked as a command line version, a subroutine version and an online version. Examples of exclusion bounds obtained with HiggsBounds are discussed for the Standard Model, for a model with a fourth generation of quarks and leptons and for the Minimal Supersymmetric Standard Model with and without CP-violation. The experimental information on the exclusion bounds currently implemented in HiggsBounds will be updated as new results from the Higgs searches become available.
5d Higgs branch localization, Seiberg-Witten equations and contact geometry
Pan, Yiwen
2015-01-01
In this paper we apply the idea of Higgs branch localization to 5d supersymmetric theories of vector multiplet and hypermultiplets, obtained as the rigid limit of = 1 supergravity with all auxiliary fields. On supersymmetric K-contact/Sasakian background, the Higgs branch BPS equations can be interpreted as 5d generalizations of the Seiberg-Witten equations. We discuss the properties and local behavior of the solutions near closed Reeb orbits. For U(1) gauge theories, which can be straight-forwardly generalized to theories whose gauge group can be completely broken, we show the suppression of the deformed Coulomb branch, and the partition function is dominated by 5d Seiberg-Witten solutions. For squashed S 5 and Y pq manifolds, we show the matching between poles in the perturbative Coulomb branch matrix model, and the bound on local winding numbers of the BPS solutions.
A PSL Bounded Model Checking Method
Institute of Scientific and Technical Information of China (English)
YU Lei; ZHAO Zongtao
2012-01-01
SAT-based bounded model checking （BMC） is introduced as an important complementary technique to OBDD-based symbolic model checking, and is an efficient verification method for parallel and reactive systems. However, until now the properties verified by bounded model checking are very finite. Temporal logic PSL is a property specification language （IEEE-1850） describing parallel systems and is divided into two parts, i.e. the linear time logic FL and the branch time logic OBE. In this paper, the specification checked by BMC is extended to PSL and its algorithm is also proposed. Firstly, define the bounded semantics of PSL, and then reduce the bounded semantics into SAT by translating PSL specification formula and the state transition relation of the system to the propositional formula A and B, respectively. Finally, verify the satisfiability of the conjunction propositional formula of A and B. The algorithm results in the translation of the existential model checking of the temporal logic PSL into the satisfiability problem of propositional formula. An example of a queue controlling circuit is used to interpret detailedly the executing procedure of the algorithm.
Logic, planning agency and branching time
Ricardo Souza Silvestre
2010-01-01
The purpose of this paper is to give a formal account of a kind of agency so far neglected in the field of philosophical modal logic of action: planning agency. In doing this we follow the standard approach of modal logics of agency exemplified by the works of Belnap, Chellas and Pörn. Since we believe there is a close relation between planning, time and indeterminism, we use the theory of branching time as a conceptual framework for investigating the basic features of planning agency. Beside...
Bounds for graph regularity and removal lemmas
Conlon, David
2011-01-01
We show, for any positive integer k, that there exists a graph in which any equitable partition of its vertices into k parts has at least ck^2/\\log^* k pairs of parts which are not \\epsilon-regular, where c,\\epsilon>0 are absolute constants. This bound is tight up to the constant c and addresses a question of Gowers on the number of irregular pairs in Szemer\\'edi's regularity lemma. In order to gain some control over irregular pairs, another regularity lemma, known as the strong regularity lemma, was developed by Alon, Fischer, Krivelevich, and Szegedy. For this lemma, we prove a lower bound of wowzer-type, which is one level higher in the Ackermann hierarchy than the tower function, on the number of parts in the strong regularity lemma, essentially matching the upper bound. On the other hand, for the induced graph removal lemma, the standard application of the strong regularity lemma, we find a different proof which yields a tower-type bound. We also discuss bounds on several related regularity lemmas, inclu...
Structural dynamics branch research and accomplishments to FY 1992
Lawrence, Charles
1992-12-01
This publication contains a collection of fiscal year 1992 research highlights from the Structural Dynamics Branch at NASA LeRC. Highlights from the branch's major work areas--Aeroelasticity, Vibration Control, Dynamic Systems, and Computational Structural Methods are included in the report as well as a listing of the fiscal year 1992 branch publications.
Correlation Distance and Bounds for Mutual Information
Directory of Open Access Journals (Sweden)
Michael J. W. Hall
2013-09-01
Full Text Available The correlation distance quantifies the statistical independence of two classical or quantum systems, via the distance from their joint state to the product of the marginal states. Tight lower bounds are given for the mutual information between pairs of two-valued classical variables and quantum qubits, in terms of the corresponding classical and quantum correlation distances. These bounds are stronger than the Pinsker inequality (and refinements thereof for relative entropy. The classical lower bound may be used to quantify properties of statistical models that violate Bell inequalities. Partially entangled qubits can have lower mutual information than can any two-valued classical variables having the same correlation distance. The qubit correlation distance also provides a direct entanglement criterion, related to the spin covariance matrix. Connections of results with classically-correlated quantum states are briefly discussed.
DEFF Research Database (Denmark)
Emiris, Ioannis Z.; Mourrain, Bernard; Tsigaridas, Elias
2010-01-01
) resultant by means of mixed volume, as well as recent advances on aggregate root bounds for univariate polynomials, and are applicable to arbitrary positive dimensional systems. We improve upon Canny's gap theorem [7] by a factor of O(dn-1), where d bounds the degree of the polynomials, and n is the number...... bound on the number of steps that subdivision-based algorithms perform in order to isolate all real roots of a polynomial system. This leads to the first complexity bound of Milne's algorithm [22] in 2D....
Branching structure for an (L-1) random walk in random environment and its applications
Hong, Wenming
2010-01-01
By decomposing the random walk path, we construct a multitype branching process with immigration in random environment for corresponding random walk with bounded jumps in random environment. Then we give two applications of the branching structure. Firstly, we specify the explicit invariant density by a method different with the one used in Br\\'emont [3] and reprove the law of large numbers of the random walk by a method known as the environment viewed from particles". Secondly, the branching structure enables us to prove a stable limit law, generalizing the result of Kesten-Kozlov-Spitzer [11] for the nearest random walk in random environment. As a byproduct, we also prove that the total population of a multitype branching process in random environment with immigration before the first regeneration belongs to the domain of attraction of some \\kappa -stable law.
Entropy Bounds, Holographic Principle and Uncertainty Relation
Directory of Open Access Journals (Sweden)
I. V. Volovich
2001-06-01
Full Text Available Abstract: A simple derivation of the bound on entropy is given and the holographic principle is discussed. We estimate the number of quantum states inside space region on the base of uncertainty relation. The result is compared with the Bekenstein formula for entropy bound, which was initially derived from the generalized second law of thermodynamics for black holes. The holographic principle states that the entropy inside a region is bounded by the area of the boundary of that region. This principle can be called the kinematical holographic principle. We argue that it can be derived from the dynamical holographic principle which states that the dynamics of a system in a region should be described by a system which lives on the boundary of the region. This last principle can be valid in general relativity because the ADM hamiltonian reduces to the surface term.
Networks of companies and branches in Poland
Chmiel, A M; Sienkiewicz, J; Suchecki, K; Chmiel, Anna M.; Holyst, Janusz A.; Sienkiewicz, Julian; Suchecki, Krzysztof
2006-01-01
In this study we consider relations between companies in Poland taking into account common branches they belong to. It is clear that companies belonging to the same branch compete for similar customers, so the market induces correlations between them. On the other hand two branches can be related by companies acting in both of them. To remove weak, accidental links we shall use a concept of threshold filtering for weighted networks where a link weight corresponds to a number of existing connections (common companies or branches) between a pair of nodes.
Torons and D-Brane Bound States
Guralnik, Z.; Ramgoolam, S.
1997-01-01
We interpret instantons on a torus with twisted boundary conditions, in terms of bound states of branes. The interplay between the SU(N) and U(1) parts of the U(N) theory of N 4-branes allows the construction of a variety of bound states. The SU(N) and U(1) parts can contribute fractional amounts to the total instanton number which is integral. The geometry of non-self intersecting two-cycles in $T^4$ sheds some light on a number of properties of these solutions.
Creed, Peter A.; Patton, Wendy; Hood, Michelle
2010-01-01
We surveyed 506 Australian high school students on career development (exploration, planning, job-knowledge, decision-making, indecision), personal functioning (well-being, self-esteem, life satisfaction, school satisfaction) and control variables (parent education, school achievement), and tested differences among work-bound, college-bound and…
Learning within bounds and dream sleep
Geszti, T.; Pazmandi, F.
1987-12-01
In a bounded-synapses version of Hopfield's model (1984) for neural networks the quasienergy of a given memory, which is approximately equal to the depth of the corresponding energy well is calculated exactly by treating the change of a synaptic strength on learning as a random walk within bounds. Attractors corresponding to stored memories are found to be considerably flattened before serious retrieval errors arise. This allows dream sleep to be interpreted as random recall and relearning of fresh strong memories, in order to stack them on top of weak incidental memory imprints of a day.
Monotonicity and bounds on Bessel functions
Directory of Open Access Journals (Sweden)
Larry Landau
2000-07-01
Full Text Available survey my recent results on monotonicity with respect to order of general Bessel functions, which follow from a new identity and lead to best possible uniform bounds. Application may be made to the "spreading of the wave packet" for a free quantum particle on a lattice and to estimates for perturbative expansions.
An ant colony algorithm for the sequential testing problem under precedence constraints
Çatay, Bülent; Catay, Bulent; Özlük, Özgür; Ozluk, Ozgur; Ünlüyurt, Tonguç; Unluyurt, Tonguc
2008-01-01
We consider the problem of minimum cost sequential testing of a series (parallel) system under precedence constraints that can be modeled as a nonlinear integer program. We develop and implement an ant colony algorithm for the problem. We demonstrate the performance of this algorithm for special type of instances for which the optimal solutions can be found in polynomial time. In addition, we compare the performance of the algorithm with a special branch and bound algo...
Trial and Error: A new Approach to Space-Bounded Learning
DEFF Research Database (Denmark)
Ameur, F.; Fischer, Paul; Hoeffgen, H.-U.;
1996-01-01
A pac-learning algorithm is d-space bounded, if it stores at most d examples from the sample at any time. We characterize the d-space learnable concept classes. For this purpose we introduce the compression parameter of a concept class 𝒞 and design our trial and error learning algorithm. We ...
Shaik, Shahnoor S.; Obata, Toshihiro; Hebelstrup, Kim H.; Schwahn, Kevin; Fernie, Alisdair R.; Mateiu, Ramona Valentina; Blennow, Andreas
2016-01-01
Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or ...
Geology of the Cane Branch and Helton Branch watershed areas, McCreary County, Kentucky
Lyons, Erwin J.
1957-01-01
Cane Branch and Helton Branch in McCreary County, Kentucky, are about 1.4 miles apart (fig. 1). Can Branch, which is about 2.1 miles long, emptied into Hughes Fork of Beaver Creek. Its watershed area of about 1.5 square miles lies largely in the Wiborf 7 1/2-minute quadrangle (SW/4 Cumberland Falls 15-minute quadrangle), but the downstream part of the area extends northward into the Hail 7 1/2-minute quadrangle (NW/4 Cumberland Falls 15-minute quadrangle). Helton Branch, which is about 1.1 miles long, has two tributaries and empties into Little Hurricane Fork of Beaver Creek. It drains an area of about 0.8 square mile of while about 0.5 square mile is in the Hail quadrangle and the remainder in the Wilborg quadrangle. The total relief in the Can Branch area is about 500 feet and in the Helton Branch area about 400 feet. Narrow, steep-sided to canyon-like valley and winding ridges, typical of the Pottsville escarpment region, are characteristic of both areas. Thick woods and dense undergrowth cover much of the two areas. Field mapping was done on U.S. Geological Survey 7 1/2-minute maps having a scale of 1:24,000 and a contour interval of 20 feet. Elevations of lithologic contacts were determined with a barometer and a hand level. Aerial photographs were used principally to trace the cliffs formed by sandstone and conglomerate ledges. Exposures, except for those of the cliff- and ledge-forming sandstone and conglomerates, are not abundant. The most complete stratigraphic sections (secs. 3 and 4, fig. 2) in the two areas are exposed in cuts of newly completed Forest Service roads, but the rick in the upper parts of the exposures is weathered. To supplement these sections, additional sections were measured in cuts along the railroad and main highways in nor near the watersheds.
Covariant Entropy Bound and Padmanabhan's Emergent Paradigm
Hadi, H; Darabi, F
2016-01-01
The covariant entropy conjecture is invariant under time reversal and consequently its origin must be statistical rather than thermodynamical. This may impose a fundamental constraint on the number of degrees of freedom in nature. Indeed, the covariant entropy bound imposes an upper entropy bound for any physical system. Considering a cosmological system, we show that Padmanabhan's emergent paradigm, which indicates that the emergence of cosmic space is due to the discrepancy between the surface and bulk degrees of freedom, leads to a lower entropy bound. The lower and upper entropy bounds may coincide on the apparent horizon for the radiation field and dark energy with the equations of state $\\omega=\\frac{1}{3}$ and $\\omega=-1$, respectively. Moreover, the maximal entropy inside the apparent horizon occurs when it is filled completely by the radiation field or dark energy. It turns out that for dark energy case (pure de Sitter space)\\ the holographic principle is satisfied in the sense that the number of deg...
A symmetric divergence measure and its bounds
Directory of Open Access Journals (Sweden)
K. C. Jain
2011-12-01
Full Text Available A new symmetric divergence measure is proposed which is useful in comparing two probability distributions. This non-parametric measure belongs to the Csiszar's $f$ divergence class. Its properties are studied and bounds are obtained in terms of some well known divergence measures. A numerical illustration based on the probability distribution is carried out.
On Quantum Capacity and its Bound
Ohya, Masanori; Volovich, Igor V.
2004-01-01
The quantum capacity of a pure quantum channel and that of classical-quantum-classical channel are discussed in detail based on the fully quantum mechanical mutual entropy. It is proved that the quantum capacity generalizes the so-called Holevo bound.
Bin Completion Algorithms for Multicontainer Packing, Knapsack, and Covering Problems
Fukunaga, A S; 10.1613/jair.2106
2011-01-01
Many combinatorial optimization problems such as the bin packing and multiple knapsack problems involve assigning a set of discrete objects to multiple containers. These problems can be used to model task and resource allocation problems in multi-agent systems and distributed systms, and can also be found as subproblems of scheduling problems. We propose bin completion, a branch-and-bound strategy for one-dimensional, multicontainer packing problems. Bin completion combines a bin-oriented search space with a powerful dominance criterion that enables us to prune much of the space. The performance of the basic bin completion framework can be enhanced by using a number of extensions, including nogood-based pruning techniques that allow further exploitation of the dominance criterion. Bin completion is applied to four problems: multiple knapsack, bin covering, min-cost covering, and bin packing. We show that our bin completion algorithms yield new, state-of-the-art results for the multiple knapsack, bin covering,...
Command and Data Handling Branch Internship
Billings, Rachel Mae
2016-01-01
Modular Integrated Stackable Layers (MISL) is a computer system designed for simple, fast, and cost effective flexible reconfiguration in space environments such as the ISS and Orion projects for various uses. Existing applications include wireless and wired communications, data acquisition and instrumentation, and camera systems, and potential applications include bus protocol converters and subsystem control. MISL is based on Texas Instruments (TI)' MSP430 16-bit ultra-low-power microcontroller device. The purpose of my project was to integrate the MISL system with a liquid crystal display (LCD) touchscreen. The LCD, manufactured by Crystalfontz and part number CFAF320240F-035T-TS, is a 320 by 240 RGB resistive color screen including an optional carrier board. The vast majority of the project was done with Altium Designer, a tool for printed circuit board (PCB) schematic capture, 3D design, and FPGA (Field Programmable Gate Array) development. The new PCB was to allow the LCD to directly stack to the rest of MISL. Research was done with datasheets for the TI microcontroller and touchscreen display in order to meet desired hardware specifications. Documentation on prior MISL projects was also utilized. The initial step was to create a schematic for the LCD, power bus, and data bus connections between components. A layout was then designed with the required physical dimensions, routed traces and vias, power and ground planes, layer stacks, and other specified design rules such as plane clearance and hole size. Multiple consultation sessions were held with Hester Yim, the technical discipline lead for the Command and Data Handling Branch, and Christy Herring, the lead PCB layout designer in the Electronic Design and Manufacturing Branch in order to ensure proper configuration. At the moment, the PCB is awaiting revision by the latter-mentioned branch. Afterwards, the board will begin to undergo the manufacturing and testing process. Throughout the internship at
Data streams algorithms and applications
Muthukrishnan, S
2014-01-01
Data stream algorithms as an active research agenda emerged only over the past few years, even though the concept of making few passes over the data for performing computations has been around since the early days of Automata Theory. The data stream agenda now pervades many branches of Computer Science including databases, networking, knowledge discovery and data mining, and hardware systems. Industry is in synch too, with Data Stream Management Systems (DSMSs) and special hardware to deal with data speeds. Even beyond Computer Science, data stream concerns are emerging in physics, atmospheric
Generalized weights and bounds for error probability over erasure channels
Lemes, Leandro Cruvinel; Firer, Marcelo
2014-01-01
New upper and lower bounds for the error probability over an erasure channel are provided, making use of Wei's generalized weights, hierarchy and spectra. In many situations the upper and lower bounds coincide and this allows improvement of existing bounds. Results concerning MDS and AMDS codes are deduced from those bounds.
Higher order branching of periodic orbits from polynomial isochrones
Directory of Open Access Journals (Sweden)
B. Toni
1999-09-01
Full Text Available We discuss the higher order local bifurcations of limit cycles from polynomial isochrones (linearizable centers when the linearizing transformation is explicitly known and yields a polynomial perturbation one-form. Using a method based on the relative cohomology decomposition of polynomial one-forms complemented with a step reduction process, we give an explicit formula for the overall upper bound of branch points of limit cycles in an arbitrary $n$ degree polynomial perturbation of the linear isochrone, and provide an algorithmic procedure to compute the upper bound at successive orders. We derive a complete analysis of the nonlinear cubic Hamiltonian isochrone and show that at most nine branch points of limit cycles can bifurcate in a cubic polynomial perturbation. Moreover, perturbations with exactly two, three, four, six, and nine local families of limit cycles may be constructed.
Hierarchical Ring Network Design Using Branch-and-Price
DEFF Research Database (Denmark)
Thomadsen, Tommy; Stidsen, Thomas K.
2005-01-01
We consider the problem of designing hierarchical two layer ring networks. The top layer consists of a federal-ring which establishes connection between a number of node disjoint metro-rings in a bottom layer. The objective is to minimize the costs of links in the network, taking both the fixed...... link establishment costs and the link capacity costs into account. Hierarchical ring network design problems combines the following optimization problems: Clustering, hub selection, metro ring design, federal ring design and routing problems. In this paper a branch-and-price algorithm is presented...... for jointly solving the clustering problem, the metro ring design problem and the routing problem. Computational results are given for networks with up to 36 nodes....
Sharp Bounds for Symmetric and Asymmetric Diophantine Approximation
Institute of Scientific and Technical Information of China (English)
Cornelis KRAAIKAMP; Ionica SMEETS
2011-01-01
In 2004,Tong found bounds for the approximation quality of a regular continued fraction convergent to a rational number,expressed in bounds for both the previous and next approximation.The authors sharpen his results with a geometric method and give both sharp upper and lower bounds.The asymptotic frequencies that these bounds occur are also calculated.
Design of Hierarchical Ring Networks Using Branch-and-Price
DEFF Research Database (Denmark)
Thomadsen, Tommy; Stidsen, Thomas K.
2004-01-01
We consider the problem of designing hierarchical two layer ring networks. The top layer consists of a federal-ring which establishes connection between a number of node disjoint metro-rings in a bottom layer. The objective is to minimize the costs of links in the network, taking both the fixed...... link establishment costs and the link capacity costs into account. The hierarchical two layer ring network design problem is solved in two stages: First the bottom layer, i.e. the metro-rings are designed, implicitly taking into account the capacity cost of the federal-ring. Then the federal......-ring is designed connecting the metro-rings, minimizing fixed link establishment costs of the federal-ring. A branch-and-price algorithm is presented for the design of the bottom layer and it is suggested that existing methods are used for the design of the federal-ring. Computational results are given...
Institute of Scientific and Technical Information of China (English)
雷友诚; 涂祖耀; 桂卫华; 吴志飞; 闫福全
2011-01-01
Aiming at the distribution of railway line and a combinatorial mode of placing-in and taking-out wagons at an enterprise railway freight station, a mathematical model of optimal operation for placing-in and taking-out wagons in the branch-shaped private line was established, which is deduced as a typical traveling salesman problem(TSP). Meanwhile, a combination of genetic algorithm and ant colony algorithm called GACA was presented to resolve the large-scale combinatorial optimization problem. The genetic algorithm was adopted to generate pheromone to distribute. And the ant colony algorithm was used to find an accurate solution. As a result, the searching efficiency and the time efficiency of the combinatorial algorithm are both greatly improved. Combined with an example, the optimal solution of the placing-in and taking-out wagons problem is found.%针对企业铁路货运站的铁路线分布特点和“连送带取”的作业方式,建立树枝型专用线取送车的数学模型,将其归纳为一个典型的旅行商问题.同时提出一种融合遗传算法和蚁群算法特点的遗传蚁群算法(GACA)来解决这种大规模组合优化问题；采用遗传算法生成信息素分布,利用蚁群算法求精确解,有效提高算法的时间效率和求解效率.结合实例计算求得了企业取送车作业问题的最优解.
HiggsBounds: Confronting Arbitrary Higgs Sectors with Exclusion Bounds from LEP and the Tevatron
Bechtle, Philip; Heinemeyer, Sven; Weiglein, Georg; Williams, Karina E
2008-01-01
HiggsBounds is a computer code that tests theoretical predictions of models with arbitrary Higgs sectors against the exclusion bounds obtained from the Higgs searches at LEP and the Tevatron. The included experimental information comprises exclusion bounds at 95% C.L. on topological cross sections. In order to determine which search topology has the highest exclusion power, the program also includes, for each topology, information from the experiments on the expected exclusion bound, which would have been observed in case of a pure background distribution. Using the predictions of the desired model provided by the user as input, HiggsBounds determines the most sensitive channel and tests whether the considered parameter point is excluded at the 95% C.L. HiggsBounds is available as a Fortran 77 and Fortran 90 code. The code can be invoked as a command line version, a subroutine version and an online version. Examples of exclusion bounds obtained with HiggsBounds are discussed for a model with a fourth generati...
POISSON REPRESENTATIONS OF BRANCHING MARKOV AND MEASURE-VALUED BRANCHING PROCESSES
Kurtz, Thomas G.; Rodrigues, Eliane R.
2011-01-01
Representations of branching Markov processes and their measure-valued limits in terms of countable systems of particles are constructed for models with spatially varying birth and death rates. Each particle has a location and a "level," but unlike earlier constructions, the levels change with time.
Mutual information rate and bounds for it.
Directory of Open Access Journals (Sweden)
Murilo S Baptista
Full Text Available The amount of information exchanged per unit of time between two nodes in a dynamical network or between two data sets is a powerful concept for analysing complex systems. This quantity, known as the mutual information rate (MIR, is calculated from the mutual information, which is rigorously defined only for random systems. Moreover, the definition of mutual information is based on probabilities of significant events. This work offers a simple alternative way to calculate the MIR in dynamical (deterministic networks or between two time series (not fully deterministic, and to calculate its upper and lower bounds without having to calculate probabilities, but rather in terms of well known and well defined quantities in dynamical systems. As possible applications of our bounds, we study the relationship between synchronisation and the exchange of information in a system of two coupled maps and in experimental networks of coupled oscillators.
Mutual information rate and bounds for it.
Baptista, Murilo S; Rubinger, Rero M; Viana, Emilson R; Sartorelli, José C; Parlitz, Ulrich; Grebogi, Celso
2012-01-01
The amount of information exchanged per unit of time between two nodes in a dynamical network or between two data sets is a powerful concept for analysing complex systems. This quantity, known as the mutual information rate (MIR), is calculated from the mutual information, which is rigorously defined only for random systems. Moreover, the definition of mutual information is based on probabilities of significant events. This work offers a simple alternative way to calculate the MIR in dynamical (deterministic) networks or between two time series (not fully deterministic), and to calculate its upper and lower bounds without having to calculate probabilities, but rather in terms of well known and well defined quantities in dynamical systems. As possible applications of our bounds, we study the relationship between synchronisation and the exchange of information in a system of two coupled maps and in experimental networks of coupled oscillators. PMID:23112809
Modeling of branching density and branching distribution in low-density polyethylene polymerization
D.M. Kim; P.D. Iedema
2008-01-01
Low-density polyethylene (ldPE) is a general purpose polymer with various applications. By this reason, many publications can be found on the ldPE polymerization modeling. However, scission reaction and branching distribution are only recently considered in the modeling studies due to difficulties i
Locating dominating codes: Bounds and extremal cardinalities
Cáceres, José; Mora, Mercè; Pelayo, Ignacio M; Puertas, María Luz
2012-01-01
In this work, two types of codes such that they both dominate and locate the vertices of a graph are studied. Those codes might be sets of detectors in a network or processors controlling a system whose set of responses should determine a malfunctioning processor or an intruder. Here, we present our more significant contributions on \\lambda-codes and \\eta-codes concerning concerning bounds, extremal values and realization theorems.
Deregulation of Bank Entry and Branching: Impact on Competition
Milo, Melanie S.
2001-01-01
This paper looks at public policy towards bank entry and branching in the Philippines and its impact on the sectors structure, conduct and performance. In particular, it argues that regulatory restrictions on bank entry and branching have had adverse effects on competition, while the liberalization of these restrictions have led to a more competitive banking sector. The paper has two main sections. Section II presents the history of regulation of bank entry and branching in the Philippines. ...
Tsirelson's bound and supersymmetric entangled states
Borsten, L; Duff, M J
2012-01-01
In order to see whether superqubits are more nonlocal than ordinary qubits, we construct a class of two-superqubit entangled states as a nonlocal resource in the CHSH game. Since super Hilbert space amplitudes are Grassmann numbers, the result depends on how we extract real probabilities and we examine three choices of map: (1) DeWitt (2) Trigonometric (3) Modified Rogers. In cases (1) and (2) the winning probability reaches the Tsirelson bound p(win) = cos^2 pi/8 \\simeq 0.8536 of standard quantum mechanics. Case (3) crosses Tsirelson's bound with p(win) = 0.9265. Although all states used in the game involve probabilities lying between 0 and 1, case (3) permits other changes of basis inducing negative transition probabilities.
模具零件的最小包围盒生成算法%Generation algorithm of minimum bounding box for die & mould components
Institute of Scientific and Technical Information of China (English)
孔垂品; 牛强; 柳伟; 周雄辉
2014-01-01
提出一种实用的最小包围盒算法，将任意位置的复杂三维模型投影在3个主平面上，通过分析投影外轮廓的最小包围矩形来最终确定三维模型的最小包围盒。算法不再采用传统算法中旋转模型的方法，而根据旋转投影的外轮廓来确定最小包围盒，提高了算法的效率。同时算法通过分析识别模型的基本形状，将其分为箱体类、回转类和异形类，以快速确定一个主投影方向，将三维问题转化为求二维平面上的最小包围矩形，进一步提高了计算效率。算法可以嵌入NX等商用CAD系统，经过大量测试对比，相对传统算法更高效，并且稳定可靠，可广泛应用于任意位置的复杂模具零件的生成和干涉检查等。%A practical algorithm of minimum bounding box was proposed in which a com-plex 3D model at arbitrary position is projected on three principal planes; and then the minimum bounding box of the 3D model is determined by analyzing the minimum bound-ing rectangle of outer contour projection. The algorithm no longer uses the rotating model in traditional method; the minimum bounding box is determined according to the outer con-tour of rotating projection to improve the efficiency. The algorithm classifies the basic shape of models as box type, rotary type and abnormal type to rapidly determine a main direction of projection. It translates the 3D problem into the minimum bounding rectangle on 2D plane to further improve the computational efficiency. The algorithm can be implant-ed in the commercial CAD system such as NX and so on. The application can be in the blank generation and interference checking of complex die & mould components at arbi-trary position.
Moment Problems on Bounded and Unbounded Domains
Directory of Open Access Journals (Sweden)
Octav Olteanu
2013-01-01
Full Text Available Using approximation results, we characterize the existence of the solution for a two-dimensional moment problem in the first quadrant, in terms of quadratic forms, similar to the one-dimensional case. For the bounded domain case, one considers a space of complex analytic functions in a disk and a space of continuous functions on a compact interval. The latter result seems to give sufficient (and necessary conditions for the existence of a multiplicative solution.
Of Models and Machines: Implementing Bounded Rationality.
Dick, Stephanie
2015-09-01
This essay explores the early history of Herbert Simon's principle of bounded rationality in the context of his Artificial Intelligence research in the mid 1950s. It focuses in particular on how Simon and his colleagues at the RAND Corporation translated a model of human reasoning into a computer program, the Logic Theory Machine. They were motivated by a belief that computers and minds were the same kind of thing--namely, information-processing systems. The Logic Theory Machine program was a model of how people solved problems in elementary mathematical logic. However, in making this model actually run on their 1950s computer, the JOHNNIAC, Simon and his colleagues had to navigate many obstacles and material constraints quite foreign to the human experience of logic. They crafted new tools and engaged in new practices that accommodated the affordances of their machine, rather than reflecting the character of human cognition and its bounds. The essay argues that tracking this implementation effort shows that "internal" cognitive practices and "external" tools and materials are not so easily separated as they are in Simon's principle of bounded rationality--the latter often shaping the dynamics of the former. PMID:26685521
Upper and lower bounds on quantum codes
Smith, Graeme Stewart Baird
This thesis provides bounds on the performance of quantum error correcting codes when used for quantum communication and quantum key distribution. The first two chapters provide a bare-bones introduction to classical and quantum error correcting codes, respectively. The next four chapters present achievable rates for quantum codes in various scenarios. The final chapter is dedicated to an upper bound on the quantum channel capacity. Chapter 3 studies coding for adversarial noise using quantum list codes, showing there exist quantum codes with high rates and short lists. These can be used, together with a very short secret key, to communicate with high fidelity at noise levels for which perfect fidelity is, impossible. Chapter 4 explores the performance of a family of degenerate codes when used to communicate over Pauli channels, showing they can be used to communicate over almost any Pauli channel at rates that are impossible for a nondegenerate code and that exceed those of previously known degenerate codes. By studying the scaling of the optimal block length as a function of the channel's parameters, we develop a heuristic for designing even better codes. Chapter 5 describes an equivalence between a family of noisy preprocessing protocols for quantum key distribution and entanglement distillation protocols whose target state belongs to a class of private states called "twisted states." In Chapter 6, the codes of Chapter 4 are combined with the protocols of Chapter 5 to provide higher key rates for one-way quantum key distribution than were previously thought possible. Finally, Chapter 7 presents a new upper bound on the quantum channel capacity that is both additive and convex, and which can be interpreted as the capacity of the channel for communication given access to side channels from a class of zero capacity "cloning" channels. This "clone assisted capacity" is equal to the unassisted capacity for channels that are degradable, which we use to find new upper
Preventing Death and Serious Injury from Falling Trees and Branches
Brookes, Andrew
2007-01-01
Of 128 outdoor education related deaths examined since 1960, 14 have been due to falling trees or branches. This article examines the grounds on which death or serious injury due to falling trees or branches can be regarded as an inherent risk in outdoor education, and the extent to which such incidents can be regarded as preventable. It compares…
[Variability of the celiac artery and its branches in sheep].
Karmona, Kh; Kovachev, G
1985-01-01
Contrast matter was used with a total of 363 sheep fetuses, newborn lambs, and adult sheep to study the variability of the coeliac artery and its branches. It was found that the artery and some of its branches, such as arteria ruminalis sinistra, arteria reticularis, and arteria lienalis often showed variations, resp., deviations in their branching and distribution. Others, such as arteria ruminalis dextra and arteria hepatica showed no variations whatever. Both the coeliac artery and the anterior intestinal artery in the sheep were most often shown to branch from the aorta alone (in 71.07 per cent of the cases) as against the rarely observed common truncus coeliacomesentericus (in 28.93 per cent of the cases). The most commonly observed form of branching of arteria coeliaca seemed to be tripus coeliacus, while the branching with the formation of a short truncus hepatogastricus was comparatively a rare phenomenon. It was also established that the left ruminal artery was much more frequently the branch of truncus lienoruminalis than the branch of arteria gastrica sinistra. So far as the place in which arteria reticularis arose three variants were observed. Most frequently this artery was shown to be the branch of arteria gastrica sinistra. PMID:4013078
Branch structure of corona discharge: experimental simulation and chemical properties
International Nuclear Information System (INIS)
The branch structure of corona discharge has been investigated via C2H2 corona discharge. Carbon filament with excellent branch structure is formed in the discharge. This carbon filament offers a direct mimic of the branch structure of corona discharge. It provides a very useful way to study on the average energy, physical and chemical characteristics of corona discharge. On this basis, the chemical property of corona discharge for methane conversion is discussed. (authors)
Solving Integer Programming Problems by Using Artificial Bee Colony Algorithm
Akay, Bahriye; Karaboga, Dervis
This paper presents a study that applies the Artificial Bee Colony algorithm to integer programming problems and compares its performance with those of Particle Swarm Optimization algorithm variants and Branch and Bound technique presented to the literature. In order to cope with integer programming problems, in neighbour solution production unit, solutions are truncated to the nearest integer values. The experimental results show that Artificial Bee Colony algorithm can handle integer programming problems efficiently and Artificial Bee Colony algorithm can be considered to be very robust by the statistics calculated such as mean, median, standard deviation.
Bounded rationality and heterogeneous expectations in macroeconomics
D. Massaro
2012-01-01
This thesis studies the effect of individual bounded rationality on aggregate macroeconomic dynamics. Boundedly rational agents are specified as using simple heuristics in their decision making. An important aspect of the type of bounded rationality described in this thesis is that the population of
Upper Bounds on the Number of Errors Corrected by the Koetter–Vardy Algorithm
DEFF Research Database (Denmark)
Justesen, Jørn
2007-01-01
By introducing a few simplifying assumptions we derive a simple condition for successful decoding using the Koetter-Vardy algorithm for soft-decision decoding of Reed-Solomon codes. We show that the algorithm has a significant advantage over hard decision decoding when the code rate is low, when ...... two or more sets of received symbols have substantially different reliabilities, or when the number of alternative transmitted symbols is very small....
20 CFR 422.5 - District offices and branch offices.
2010-04-01
... Section 422.5 Employees' Benefits SOCIAL SECURITY ADMINISTRATION ORGANIZATION AND PROCEDURES Organization and Functions of the Social Security Administration § 422.5 District offices and branch offices. There are over 700 social security district offices and branch offices located in the principal cities...
Synthesis and Characterization of Branched Poly(ester urea)s with Different Branch Density
Yu, Jiayi; Becker, Matthew
2015-03-01
A new class of L-phenylalanine-based poly(ester urea)s (PEU) was developed that possess tunable mechanical properties, water uptake ability and degradation rates. Our preliminary data has shown that 1,6-hexanediol L - phenylalanine-based poly(ester urea)s possesses an elastic modulus nearly double that of poly(lactic acid). My work details the synthesis of a series of L - phenylalanine-based poly(ester urea)s possessing a variation in diol chain length and in branch density and shows how these subtle structural differences influence the mechanical properties and in vitro biodegradation rates. The elastic moduli span a range of values that overlap with several currently clinically available degradable polymers. Increasingly the diol chain lengths increases the amount of flexible segment in the chemical structure, which results in reduced elastic modulus values and increased values of elongation at break. Increasing the amount of branch monomer incorporated into the system reduces the molecular entanglement, which also results in decreased elastic modulus values and increased values of elongation at break. The L - phenylalanine-based poly(ester urea)s also exhibited a diol length dependent degradation process that varied between 1-5 % over 16 weeks. Compared with PLLA, PEUs degrade more quickly and the rate can be tuned by changing the diol chain length. PEUs absorb more water and the water uptake ability can be tuned by changing the branch density. This work was supported by Akron Functional Materials Center.
CYANOGEN IN NGC 1851 RED GIANT BRANCH AND ASYMPTOTIC GIANT BRANCH STARS: QUADRIMODAL DISTRIBUTIONS
Energy Technology Data Exchange (ETDEWEB)
Campbell, S. W.; Stancliffe, R. J.; Lattanzio, J. C.; Angelou, G. C.; D' Orazi, V. [Monash Centre for Astrophysics, P.O. Box 28M, Victoria 3800 (Australia); Yong, D.; Wylie-de Boer, E. C. [Research School of Astronomy and Astrophysics, Australian National University, Weston, ACT 2611 (Australia); Martell, S. L. [Australian Astronomical Observatory, North Ryde, NSW 2113 (Australia); Grundahl, F. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark); Sneden, C., E-mail: simon.campbell@monash.edu, E-mail: david.yong@anu.edu.au [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States)
2012-12-10
The Galactic globular cluster NGC 1851 has raised much interest since Hubble Space Telescope photometry revealed that it hosts a double subgiant branch. Here we report on our homogeneous study into the cyanogen (CN) band strengths in the red giant branch (RGB) population (17 stars) and asymptotic giant branch (AGB) population (21 stars) using AAOmega/2dF spectra with R {approx} 3000. We discover that NGC 1851 hosts a quadrimodal distribution of CN band strengths in its RGB and AGB populations. This result supports the merger formation scenario proposed for this cluster, such that the CN quadrimodality could be explained by the superposition of two 'normal' bimodal populations. A small sample overlap with an abundance catalog allowed us to tentatively explore the relationship between our CN populations and a range of elemental abundances. We found a striking correlation between CN and [O/Na]. We also found that the four CN peaks may be paired-the two CN-weaker populations being associated with low Ba and the two CN-stronger populations with high Ba. If true, then s-process abundances would be a good diagnostic for disentangling the two original clusters in the merger scenario. More observations are needed to confirm the quadrimodality and also the relationship between the subpopulations. We also report CN results for NGC 288 as a comparison. Our relatively large samples of AGB stars show that both clusters have a bias toward CN-weak AGB populations.
Bounded fractional diffusion in geological media: Definition and Lagrangian approximation
Zhang, Yong; Green, Christopher T.; LaBolle, Eric M.; Neupauer, Roseanna M.; Sun, HongGuang
2016-01-01
Spatiotemporal Fractional-Derivative Models (FDMs) have been increasingly used to simulate non-Fickian diffusion, but methods have not been available to define boundary conditions for FDMs in bounded domains. This study defines boundary conditions and then develops a Lagrangian solver to approximate bounded, one-dimensional fractional diffusion. Both the zero-value and non-zero-value Dirichlet, Neumann, and mixed Robin boundary conditions are defined, where the sign of Riemann-Liouville fractional derivative (capturing non-zero-value spatial-nonlocal boundary conditions with directional super-diffusion) remains consistent with the sign of the fractional-diffusive flux term in the FDMs. New Lagrangian schemes are then proposed to track solute particles moving in bounded domains, where the solutions are checked against analytical or Eularian solutions available for simplified FDMs. Numerical experiments show that the particle-tracking algorithm for non-Fickian diffusion differs from Fickian diffusion in relocating the particle position around the reflective boundary, likely due to the non-local and non-symmetric fractional diffusion. For a non-zero-value Neumann or Robin boundary, a source cell with a reflective face can be applied to define the release rate of random-walking particles at the specified flux boundary. Mathematical definitions of physically meaningful nonlocal boundaries combined with bounded Lagrangian solvers in this study may provide the only viable techniques at present to quantify the impact of boundaries on anomalous diffusion, expanding the applicability of FDMs from infinite do mains to those with any size and boundary conditions.
Valuation models and Simon's bounded rationality
Directory of Open Access Journals (Sweden)
Alexandra Strommer de Farias Godoi
2009-09-01
Full Text Available This paper aims at reconciling the evidence that sophisticated valuation models are increasingly used by companies in their investment appraisal with the literature of bounded rationality, according to which objective optimization is impracticable in the real world because it would demand an immense level of sophistication of the analytical and computational processes of human beings. We show how normative valuation models should rather be viewed as forms of reality representation, frameworks according to which the real world is perceived, fragmented for a better understanding, and recomposed, providing an orderly method for undertaking a task as complex as the investment decision.
Linear and Branched PEIs (Polyethylenimines) and Their Property Space.
Lungu, Claudiu N; Diudea, Mircea V; Putz, Mihai V; Grudziński, Ireneusz P
2016-04-13
A chemical property space defines the adaptability of a molecule to changing conditions and its interaction with other molecular systems determining a pharmacological response. Within a congeneric molecular series (compounds with the same derivatization algorithm and thus the same brute formula) the chemical properties vary in a monotonic manner, i.e., congeneric compounds share the same chemical property space. The chemical property space is a key component in molecular design, where some building blocks are functionalized, i.e., derivatized, and eventually self-assembled in more complex systems, such as enzyme-ligand systems, of which (physico-chemical) properties/bioactivity may be predicted by QSPR/QSAR (quantitative structure-property/activity relationship) studies. The system structure is determined by the binding type (temporal/permanent; electrostatic/covalent) and is reflected in its local electronic (and/or magnetic) properties. Such nano-systems play the role of molecular devices, important in nano-medicine. In the present article, the behavior of polyethylenimine (PEI) macromolecules (linear LPEI and branched BPEI, respectively) with respect to the glucose oxidase enzyme GOx is described in terms of their (interacting) energy, geometry and topology, in an attempt to find the best shape and size of PEIs to be useful for a chosen (nanochemistry) purpose.
Linear and Branched PEIs (Polyethylenimines and Their Property Space
Directory of Open Access Journals (Sweden)
Claudiu N. Lungu
2016-04-01
Full Text Available A chemical property space defines the adaptability of a molecule to changing conditions and its interaction with other molecular systems determining a pharmacological response. Within a congeneric molecular series (compounds with the same derivatization algorithm and thus the same brute formula the chemical properties vary in a monotonic manner, i.e., congeneric compounds share the same chemical property space. The chemical property space is a key component in molecular design, where some building blocks are functionalized, i.e., derivatized, and eventually self-assembled in more complex systems, such as enzyme-ligand systems, of which (physico-chemical properties/bioactivity may be predicted by QSPR/QSAR (quantitative structure-property/activity relationship studies. The system structure is determined by the binding type (temporal/permanent; electrostatic/covalent and is reflected in its local electronic (and/or magnetic properties. Such nano-systems play the role of molecular devices, important in nano-medicine. In the present article, the behavior of polyethylenimine (PEI macromolecules (linear LPEI and branched BPEI, respectively with respect to the glucose oxidase enzyme GOx is described in terms of their (interacting energy, geometry and topology, in an attempt to find the best shape and size of PEIs to be useful for a chosen (nanochemistry purpose.
Linear and Branched PEIs (Polyethylenimines) and Their Property Space
Lungu, Claudiu N.; Diudea, Mircea V.; Putz, Mihai V.; Grudziński, Ireneusz P.
2016-01-01
A chemical property space defines the adaptability of a molecule to changing conditions and its interaction with other molecular systems determining a pharmacological response. Within a congeneric molecular series (compounds with the same derivatization algorithm and thus the same brute formula) the chemical properties vary in a monotonic manner, i.e., congeneric compounds share the same chemical property space. The chemical property space is a key component in molecular design, where some building blocks are functionalized, i.e., derivatized, and eventually self-assembled in more complex systems, such as enzyme-ligand systems, of which (physico-chemical) properties/bioactivity may be predicted by QSPR/QSAR (quantitative structure-property/activity relationship) studies. The system structure is determined by the binding type (temporal/permanent; electrostatic/covalent) and is reflected in its local electronic (and/or magnetic) properties. Such nano-systems play the role of molecular devices, important in nano-medicine. In the present article, the behavior of polyethylenimine (PEI) macromolecules (linear LPEI and branched BPEI, respectively) with respect to the glucose oxidase enzyme GOx is described in terms of their (interacting) energy, geometry and topology, in an attempt to find the best shape and size of PEIs to be useful for a chosen (nanochemistry) purpose. PMID:27089324
Branched nanostructures and method of synthesizing the same
Fonseca, Luis F. (Inventor); Resto, Oscar (Inventor); Sola, Francisco (Inventor)
2009-01-01
A branched nanostructure is synthesized. A porous material, with pores having a diameter of approximately 1 .mu.m or less, is placed in a vacuum. It is irradiated with an electron beam. This causes a trunk to grow from the porous material and further causes branches to grow from the trunk.
Aggregation Dynamics Using Phase Wave Signals and Branching Patterns
Sakaguchi, Hidetsugu; Kusagaki, Takuma
2016-09-01
The aggregation dynamics of slime mold is studied using coupled equations of phase ϕ and cell concentration n. Phase waves work as tactic signals for aggregation. Branching structures appear during the aggregation. A stationary branching pattern appears like a river network, if cells are uniformly supplied into the system.
The factorization method and ground state energy bounds
Schmutz, M.
1985-04-01
We discuss the relationship between the factorization method and the Barnsley bound to the ground state energy. The latter method is extended in such a way that both lower and upper analytic bounds can be obtained.
Semiparametric bounds of mean and variance for exotic options
Institute of Scientific and Technical Information of China (English)
2009-01-01
Finding semiparametric bounds for option prices is a widely studied pricing technique.We obtain closed-form semiparametric bounds of the mean and variance for the pay-off of two exotic(Collar and Gap) call options given mean and variance information on the underlying asset price.Mathematically,we extended domination technique by quadratic functions to bound mean and variances.
Semiparametric bounds of mean and variance for exotic options
Institute of Scientific and Technical Information of China (English)
LIU GuoQing; LI V.Wenbo
2009-01-01
Finding semiparametric bounds for option prices is a widely studied pricing technique. We obtain closed-form semiparametric bounds of the mean and variance for the pay-off of two exotic (Collar and Gap) call options given mean and variance information on the underlying asset price. Mathematically, we extended domination technique by quadratic functions to bound mean and variances.
Model-Independent Analysis of B -> pi K Decays and Bounds on the Weak Phase gamma
Neubert, Matthias(PRISMA Cluster of Excellence & Mainz Institut for Theoretical Physics, Johannes Gutenberg University, D-55099, Mainz, Germany)
1998-01-01
A general parametrization of the amplitudes for the rare two-body decays B -> pi K is introduced, which makes maximal use of theoretical constraints arising from flavour symmetries of the strong interactions and the structure of the low-energy effective weak Hamiltonian. With the help of this parametrization, a model-independent analysis of the branching ratios and direct CP asymmetries in the various B -> pi K decay modes is performed, and the impact of hadronic uncertainties on bounds on th...
Improved Bounds for Beacon-Based Coverage and Routing in Simple Rectilinear Polygons
Bae, Sang Won; Shin, Chan-Su; Vigneron, Antoine
2015-01-01
We establish tight bounds for beacon-based coverage problems, and improve the bounds for beacon-based routing problems in simple rectilinear polygons. Specifically, we show that $\\lfloor \\frac{n}{6} \\rfloor$ beacons are always sufficient and sometimes necessary to cover a simple rectilinear polygon $P$ with $n$ vertices. We also prove tight bounds for the case where $P$ is monotone, and we present an optimal linear-time algorithm that computes the beacon-based kernel of $P$. For the routing p...
Institute of Scientific and Technical Information of China (English)
曾振东
2013-01-01
Bounding Box algorithm is a typical node localisation algorithm based on discrete network model in wireless sensor network (WSN).To overcome its disadvantages in low localisation accuracy and coverage rate , we propose an improved localisation algorithm which employs the virtual anchor nodes strategy .First, the unknown nodes will calculate their own coordinates by making use of the anchor nodes within their communication range .Secondly , the located unknown nodes will upgrade themselves as the virtual anchor nodes according to the promotion strategy selectively .Finally, those nodes which are unable to locate themselves will use the virtual anchor nodes to get their own location.Besides, the establishment of the network node model with double radius based on discrete network model further restrict the location of the unknown nodes .Theoretical analysis and simulation result all show that the proposed algorithm can effectively improve the localisation accuracy while significantly raise the coverage rate of localisation .%Bounding Box算法是一种典型的基于离散网络模型的无线传感器网络节点定位算法。针对Bounding Box算法定位误差大、覆盖率低的缺点，提出一种采用虚拟锚节点策略的改进定位算法。首先未知节点利用其通信范围内的锚节点进行定位；其次，已定位的节点根据升级策略有选择性的升级为虚拟锚节点；最后，无法定位的节点利用虚拟锚节点实现定位。另外，在离散网络模型的基础上，通过建立双半径网络节点模型从而进一步约束了未知节点的位置。理论分析及仿真结果均表明，该算法在显著提高定位覆盖率的同时，有效地提高了定位精度。
Consumer choice and revealed bounded rationality
Manzini, Paola; Mariotti, Marco
2006-01-01
We study two boundedly rational procedures in consumer behavior. We show that these procedures can be detected by conditions on observable demand data of the same type as standard revealed preference axioms. This provides the basis for a non-parametric analysis of boundedly rational consumer behavior mirroring the classical one for utility maximization.
Polynomially Bounded Sequences and Polynomial Sequences
Directory of Open Access Journals (Sweden)
Okazaki Hiroyuki
2015-09-01
Full Text Available In this article, we formalize polynomially bounded sequences that plays an important role in computational complexity theory. Class P is a fundamental computational complexity class that contains all polynomial-time decision problems [11], [12]. It takes polynomially bounded amount of computation time to solve polynomial-time decision problems by the deterministic Turing machine. Moreover we formalize polynomial sequences [5].
Kim, Jeong Han; Montenegro, Ravi; Peres, Yuval; Tetali, Prasad
2010-01-01
We show a Birthday Paradox for self-intersections of Markov chains with uniform stationary distribution. As an application, we analyze Pollard's Rho algorithm for finding the discrete logarithm in a cyclic group $G$ and find that if the partition in the algorithm is given by a random oracle, then with high probability a collision occurs in $\\Theta(\\sqrt{|G|})$ steps. Moreover, for the parallelized distinguished points algorithm on $J$ processors we find that $\\Theta(\\sqrt{|G|}/J)$ steps suffi...
Hyperquarks and bosonic preon bound states
Schmid, Michael L.; Buchmann, Alfons J.
2009-11-01
In a model in which leptons, quarks, and the recently introduced hyperquarks are built up from two fundamental spin-(1)/(2) preons, the standard model weak gauge bosons emerge as preon bound states. In addition, the model predicts a host of new composite gauge bosons, in particular, those responsible for hyperquark and proton decay. Their presence entails a left-right symmetric extension of the standard model weak interactions and a scheme for a partial and grand unification of nongravitational interactions based on, respectively, the effective gauge groups SU(6)P and SU(9)G. This leads to a prediction of the Weinberg angle at low energies in good agreement with experiment. Furthermore, using evolution equations for the effective coupling strengths, we calculate the partial and grand unification scales, the hyperquark mass scale, as well as the mass and decay rate of the lightest hyperhadron.
Hyperquarks and bosonic preon bound states
Schmid, Michael L
2013-01-01
In a model in which leptons, quarks, and the recently introduced hyperquarks are built up from two fundamental spin 1/2 preons, the standard model weak gauge bosons emerge as preon bound states. In addition, the model predicts a host of new composite gauge bosons, in particular those responsible for hyperquark and proton decay. Their presence entails a left-right symmetric extension of the standard model weak interactions and a scheme for a partial and grand unification of nongravitational interactions based on respectively the effective gauge groups SU(6)_P and SU(9)_G. This leads to a prediction of the Weinberg angle at low energies in good agreement with experiment. Furthermore, using evolution equations for the effective coupling strengths, we calculate the partial and grand unification scales, the hyperquark mass scale, as well as the mass and decay rate of the lightest hyperhadron.
Bounded Rationality, Retaliation, and the Spread of Urban Violence
Jacobs, Bruce A.; Wright, Richard
2010-01-01
Drawing from in-depth interviews with 52 active street criminals, this article examines the grounded theoretic implications of bounded rationality for retaliatory street violence. The bounds on rationality that this article explores are anger, uncertainty, and time pressure. These bounds create imperfections in the retaliatory decision-making…
Regret Bounds for Deterministic Gaussian Process Bandits
de Freitas, Nando; Zoghi, Masrour
2012-01-01
This paper analyses the problem of Gaussian process (GP) bandits with deterministic observations. The analysis uses a branch and bound algorithm that is related to the UCB algorithm of (Srinivas et al., 2010). For GPs with Gaussian observation noise, with variance strictly greater than zero, (Srinivas et al., 2010) proved that the regret vanishes at the approximate rate of $O(\\frac{1}{\\sqrt{t}})$, where t is the number of observations. To complement their result, we attack the deterministic case and attain a much faster exponential convergence rate. Under some regularity assumptions, we show that the regret decreases asymptotically according to $O(e^{-\\frac{\\tau t}{(\\ln t)^{d/4}}})$ with high probability. Here, d is the dimension of the search space and $\\tau$ is a constant that depends on the behaviour of the objective function near its global maximum.
Business Systems Branch Abilities, Capabilities, and Services Web Page
Cortes-Pena, Aida Yoguely
2009-01-01
During the INSPIRE summer internship I acted as the Business Systems Branch Capability Owner for the Kennedy Web-based Initiative for Communicating Capabilities System (KWICC), with the responsibility of creating a portal that describes the services provided by this Branch. This project will help others achieve a clear view ofthe services that the Business System Branch provides to NASA and the Kennedy Space Center. After collecting the data through the interviews with subject matter experts and the literature in Business World and other web sites I identified discrepancies, made the necessary corrections to the sites and placed the information from the report into the KWICC web page.
Software Management Environment (SME): Components and algorithms
Hendrick, Robert; Kistler, David; Valett, Jon
1994-01-01
This document presents the components and algorithms of the Software Management Environment (SME), a management tool developed for the Software Engineering Branch (Code 552) of the Flight Dynamics Division (FDD) of the Goddard Space Flight Center (GSFC). The SME provides an integrated set of visually oriented experienced-based tools that can assist software development managers in managing and planning software development projects. This document describes and illustrates the analysis functions that underlie the SME's project monitoring, estimation, and planning tools. 'SME Components and Algorithms' is a companion reference to 'SME Concepts and Architecture' and 'Software Engineering Laboratory (SEL) Relationships, Models, and Management Rules.'
Do Reuss and Voigt Bounds Really Bound in High-Pressure Rheology Experiments?
Energy Technology Data Exchange (ETDEWEB)
Chen,J.; Li, L.; Yu, T.; Long, H.; Weidner, D.; Wang, L.; Vaughan, M.
2006-01-01
Energy dispersive synchrotron x-ray diffraction is carried out to measure differential lattice strains in polycrystalline Fe{sub 2}SiO{sub 4} (fayalite) and MgO samples using a multi-element solid state detector during high-pressure deformation. The theory of elastic modeling with Reuss (iso-stress) and Voigt (iso-strain) bounds is used to evaluate the aggregate stress and weight parameter, {alpha} (0{le}{alpha}{le}1), of the two bounds. Results under the elastic assumption quantitatively demonstrate that a highly stressed sample in high-pressure experiments reasonably approximates to an iso-stress state. However, when the sample is plastically deformed, the Reuss and Voigt bounds are no longer valid ({alpha} becomes beyond 1). Instead, if plastic slip systems of the sample are known (e.g. in the case of MgO), the aggregate property can be modeled using a visco-plastic self-consistent theory.
Do Reuss and Voigt bounds really bound in high-pressure rheology experiments?
Energy Technology Data Exchange (ETDEWEB)
Chen Jiuhua; Li Li; Yu, Tony; Long Hongbo; Weidner, Donald; Wang Liping; Vaughan, Michael [Mineral Physics Institute and Department of Geosciences, Stony Brook University, Stony Brook, NY 11794-2100 (United States)
2006-06-28
Energy dispersive synchrotron x-ray diffraction is carried out to measure differential lattice strains in polycrystalline Fe{sub 2}SiO{sub 4} (fayalite) and MgO samples using a multi-element solid state detector during high-pressure deformation. The theory of elastic modelling with Reuss (iso-stress) and Voigt (iso-strain) bounds is used to evaluate the aggregate stress and weight parameter, {alpha} (0{<=}{alpha}{<=}1), of the two bounds. Results under the elastic assumption quantitatively demonstrate that a highly stressed sample in high-pressure experiments reasonably approximates to an iso-stress state. However, when the sample is plastically deformed, the Reuss and Voigt bounds are no longer valid ({alpha} becomes beyond 1). Instead, if plastic slip systems of the sample are known (e.g. in the case of MgO), the aggregate property can be modelled using a visco-plastic self-consistent theory.
Do Reuss and Voigt bounds really bound in high-pressure rheology experiments?
Chen, Jiuhua; Li, Li; Yu, Tony; Long, Hongbo; Weidner, Donald; Wang, Liping; Vaughan, Michael
2006-06-28
Energy dispersive synchrotron x-ray diffraction is carried out to measure differential lattice strains in polycrystalline Fe(2)SiO(4) (fayalite) and MgO samples using a multi-element solid state detector during high-pressure deformation. The theory of elastic modelling with Reuss (iso-stress) and Voigt (iso-strain) bounds is used to evaluate the aggregate stress and weight parameter, α (0≤α≤1), of the two bounds. Results under the elastic assumption quantitatively demonstrate that a highly stressed sample in high-pressure experiments reasonably approximates to an iso-stress state. However, when the sample is plastically deformed, the Reuss and Voigt bounds are no longer valid (α becomes beyond 1). Instead, if plastic slip systems of the sample are known (e.g. in the case of MgO), the aggregate property can be modelled using a visco-plastic self-consistent theory. PMID:22611095
van der Vlist, Jeroen; Reixach, Marta Palomo; van der Maarel, Marc; Dijkhuizen, Lubbert; Schouten, Arend Jan; Loos, Katja
2008-01-01
An enzymatic tandem reaction is described in which the enzymes phosphorylase and Deinococcus geothermalis glycogen branching enzyme (Dg GBE) catalyze the synthesis of branched polyglucans from glucose-1-phosphate (G-1-P). Phosphorylase consumes G-1-P and polymerizes linear amylose while DR GBE intro
Institute of Scientific and Technical Information of China (English)
李树刚; 吴智铭; 庞小红
2004-01-01
In order to study the capacitated lot sizing problem for a supply chain of corporate multi-location fac-tories to minimize the total costs of production, inventory and transportation under the system capacity restriction and product due date, while at the same time considering the menu distributed balance, the mathematical pro-gramming models are decomposed and reduced from the 3 levels into 2 levels according to the idea of just-in-time production. In order to overcome the premature convergence of ACA (ant colony algorithms) , the idea of mute operation is adopted in genetic algorithms and a PACA (parallel ant colony algorithms) is proposed forsupply chain optimization. Finally, an illustrative example is given, and a comparison is made with standard BAR ( Branch and Bound) and PACA approach. The result shows that the latter is more effective and promis-ing.
Inventory and Monitoring Plan Big Branch Marsh National Wildlife Refuge
US Fish and Wildlife Service, Department of the Interior — The Big Branch Marsh IMP was developed according to the Inventory and Monitoring (I 1) is an operational plan for one or more refuges that clearly states I 2)...
Antibiotics and renal branching morphogenesis: comparison of toxicities
Bueters, R.R.G.; Kusters, L.J.; Klaasen, A.; Heuvel, L.P.W.J. van den; Schreuder, M.F.
2014-01-01
BACKGROUND: Many premature born neonates receive antibiotic drugs to treat infections, which are applied during active nephrogenesis. We studied the impact of clinical concentrations of gentamicin and alternatives, ceftazidime and meropenem, on ureteric branching. METHODS: Mice metanephroi were diss
Models and Techniques for Proving Data Structure Lower Bounds
DEFF Research Database (Denmark)
Larsen, Kasper Green
In this dissertation, we present a number of new techniques and tools for proving lower bounds on the operational time of data structures. These techniques provide new lines of attack for proving lower bounds in both the cell probe model, the group model, the pointer machine model and the I....../O-model. In all cases, we push the frontiers further by proving lower bounds higher than what could possibly be proved using previously known techniques. For the cell probe model, our results have the following consequences: The rst (lg n) query time lower bound for linear space static data structures....... The highest previous lower bound for any static data structure problem peaked at (lg n= lg lg n). An ((lg n= lg lg n)2) lower bound on the maximum of the update time and the query time of dynamic data structures. This is almost a quadratic improvement over the highest previous lower bound of (lg n...
Size-exclusion chromatography (SEC) of branched polymers and polysaccharides
Gaborieau, Marianne; Castignolles, Patrice
2010-01-01
Branched polymers are among the most important polymers, ranging from polyolefins to polysaccharides. Branching plays a key role in the chain dynamics. It is thus very important for application properties such as mechanical and adhesive properties and digestibility. It also plays a key role in viscous properties, and thus in the mechanism of the separation of these polymers in size-exclusion chromatography (SEC). Critically reviewing the literature, particularly on SEC of polyolefins, polyacr...
Coset construction of logarithmic minimal models: branching rules and branching functions
Pearce, Paul A
2013-01-01
Working in the Virasoro picture, it is argued that the logarithmic minimal models LM(p,p')=LM(p,p';1) can be extended to an infinite hierarchy of logarithmic conformal field theories LM(p,p';n) at higher fusion levels n=1,2,3,.... From the lattice, these theories are constructed by fusing together n x n elementary faces of the appropriate LM(p,p') models. It is further argued that all of these logarithmic theories are realized as diagonal cosets (A_1^{(1)})_k \\oplus (A_1^{(1)})_n / (A_1^{(1)})_{k+n} where n is the integer fusion level and k=np/(p'-p)-2 is a fractional level. These cosets mirror the cosets of the higher fusion level minimal models of the form M(m,m';n), but are associated with certain reducible representations. We present explicit branching rules for characters in the form of multiplication formulas arising in the logarithmic limit of the usual Goddard-Kent-Olive coset construction of the non-unitary minimal models M(m,m';n). The limiting branching functions play the role of Kac characters for...
F-Theory, spinning black holes and multi-string branches
Haghighat, Babak; Murthy, Sameer; Vafa, Cumrun; Vandoren, Stefan
2016-01-01
We study 5d supersymmetric black holes which descend from strings of generic N=(1,0) supergravity in 6d. These strings have an F-theory realization in 6d as D3 branes wrapping smooth genus g curves in the base of elliptic 3-folds. They enjoy (0 , 4) worldsheet supersymmetry with an extra SU(2) L current algebra at level g realized on the left-movers. When the smooth curves degenerate they lead to multi-string branches and we find that the microscopic worldsheet theory flows in the IR to disconnected 2d CFTs having different central charges. The single string sector is the one with maximal central charge, which when wrapped on a circle, leads to a 5d spinning BPS black hole whose horizon volume agrees with the leading entropy prediction from the Cardy formula. However, we find new phenomena where this branch meets other branches of the CFT. These include multi-string configurations which have no bound states in 6 dimensions but are bound through KK momenta when wrapping a circle, as well as loci where the curves degenerate to spheres. These loci lead to black hole configurations which can have total angular momentum relative to a Taub-Nut center satisfying J 2 > M 3 and whose number of states, though exponentially large, grows much slower than those of the large spinning black hole.
Design and Performance Evaluation of Sequence Partition Algorithms
Institute of Scientific and Technical Information of China (English)
Bing Yang; Jing Chen; En-Yue Lu; Si-Qing Zheng
2008-01-01
Tradeoffs between time complexities and solution optimalities are important when selecting algorithms for an NP-hard problem in different applications. Also, the distinction between theoretical upper bound and actual solution optimality for realistic instances of an NP-hard problem is a factor in selecting algorithms in practice. We consider the problem of partitioning a sequence of n distinct numbers into minimum number of monotone (increasing or decreasing) case. We introduce a new algorithm, the modified version of the Yehuda-Fogel algorithm, that computes a solution of no on three algorithms, a known approximation algorithm of approximation ratio 1.71 and time complexity O(n3), a known greedy algorithm of time complexity O(n1.5 log n), and our new modified Yehuda-Fogel algorithm. Our results show that the solutions computed by the greedy algorithm and the modified Yehuda-Fogel algorithm are close to that computed by the approximation algorithm even though the theoretical worst-case error bounds of these two algorithms are not proved to be within a constant time of the optimal solution. Our study indicates that for practical use the greedy algorithm and the modified Yehuda-Fogel algorithm can be good choices if the running time is a major concern.
Directory of Open Access Journals (Sweden)
Daniela J. López-Araujo
2013-01-01
Full Text Available In this work, an output‐feedback adaptive SP‐SD‐type control scheme for the global position stabilization of robot manipulators with bounded inputs is proposed. Compared with the output‐feedback adaptive approaches previously developed in a bounded‐ input context, the proposed velocity‐free feedback controller guarantees the adaptive regulation objective globally (i.e. for any initial condition, avoiding discontinuities throughout the scheme, preventing the inputs from reaching their natural saturation bounds and imposing no saturation-avoidance restrictions on the choice of the P and D control gains. Moreover, through its extended structure, the adaptation algorithm may be configured to evolve either in parallel (independently or interconnected to the velocity estimation (motion dissipation auxiliary dynamics, giving an additional degree of design flexibility. Furthermore, the proposed scheme is not restricted to the use of a specific saturation function to achieve the required boundedness, but may involve any one within a set of smooth and non‐smooth (Lipschitz‐continuous bounded passive functions that include the hyperbolic tangent and the conventional saturation as particular cases. Experimental results on a 3‐ degree‐of‐freedom manipulator corroborate the efficiency of the proposed scheme.
F-Theory, Spinning Black Holes and Multi-string Branches
Haghighat, Babak; Vafa, Cumrun; Vandoren, Stefan
2015-01-01
We study 5d supersymmetric black holes which descend from strings of generic $\\mathcal{N}=(1,0)$ supergravity in 6d. These strings have an F-theory realization in 6d as D3 branes wrapping smooth genus $g$ curves in the base of elliptic 3-folds. They enjoy $(0,4)$ worldsheet supersymmetry with an extra $SU(2)_L$ current algebra at level $g$ realized on the left-movers. When the smooth curves degenerate they lead to multi-string branches and we find that the microscopic worldsheet theory flows in the IR to disconnected 2d CFTs having different central charges. The single string sector is the one with maximal central charge, which when wrapped on a circle, leads to a 5d spinning BPS black hole whose horizon volume agrees with the leading entropy prediction from the Cardy formula. However, we find new phenomena where this branch meets other branches of the CFT. These include multi-string configurations which have no bound states in 6 dimensions but are bound through KK momenta when wrapping a circle, as well as l...
Decoherence and the Branching of Chaos-less Classical Trajectory
Ishikawa, Takuji
2016-01-01
This study was started to know mysterious classicality of nuclei. This time, I found a new rule for decoherence. I used a model without chaos. As a result, it was shown that not only the intersection of classical trajectories but also branching of classical trajectories are needed for decoherence. In other words, it was shown that interactions between a main system and environments have to make enough branchings of classical trajectories of the main system for decoherence.
Optimization algorithms and applications
Arora, Rajesh Kumar
2015-01-01
Choose the Correct Solution Method for Your Optimization ProblemOptimization: Algorithms and Applications presents a variety of solution techniques for optimization problems, emphasizing concepts rather than rigorous mathematical details and proofs. The book covers both gradient and stochastic methods as solution techniques for unconstrained and constrained optimization problems. It discusses the conjugate gradient method, Broyden-Fletcher-Goldfarb-Shanno algorithm, Powell method, penalty function, augmented Lagrange multiplier method, sequential quadratic programming, method of feasible direc
Properties and for Bounded Linear Operators
Directory of Open Access Journals (Sweden)
M. H. M. Rashid
2013-01-01
Full Text Available We shall consider properties which are related to Weyl type theorem for bounded linear operators , defined on a complex Banach space . These properties, that we call property , means that the set of all poles of the resolvent of of finite rank in the usual spectrum are exactly those points of the spectrum for which is an upper semi-Fredholm with index less than or equal to 0 and we call property , means that the set of all poles of the resolvent of in the usual spectrum are exactly those points of the spectrum for which is an upper semi--Fredholm with index less than or equal to 0. Properties and are related to a strong variants of classical Weyl’s theorem, the so-called property and property We shall characterize properties and in several ways and we shall also describe the relationships of it with the other variants of Weyl type theorems. Our main tool is localized version of the single valued extension property. Also, we consider the properties and in the frame of polaroid type operators.
Real weights, bound states and duality orbits
Marrani, Alessio; Romano, Luca
2015-01-01
We show that the duality orbits of extremal black holes in supergravity theories with symmetric scalar manifolds can be derived by studying the stabilizing subalgebras of suitable representatives, realized as bound states of specific weight vectors of the corresponding representation of the duality symmetry group. The weight vectors always correspond to weights that are real, where the reality properties are derived from the Tits-Satake diagram that identifies the real form of the Lie algebra of the duality symmetry group. Both N=2 magic Maxwell-Einstein supergravities and the semisimple infinite sequences of N=2 and N=4 theories in D=4 and 5 are considered, and various results, obtained over the years in the literature using different methods, are retrieved. In particular, we show that the stratification of the orbits of these theories occurs because of very specific properties of the representations: in the case of the theory based on the real numbers, whose symmetry group is maximally non-compact and there...
Bounded Rationality and Tacit Knowledge in the Organizational Capabilities Approach
Foss, Nikolaj J.
2004-01-01
The famous three chapters in Nelson and Winter (1982) that focus on firm routines and capabilities are often taken to be solidly founded on an assumption of bounded rationality. I argue that, in actuality, bounded rationality plays a rather limited role in Nelson and Winter (1982), that the very different assumption of tacit knowledge is much more central, and that the links between bounded rationality and routines/capabilities are not clear. I then argue that the absence in Nelson and Winter...
Tensor Squeezed Limits and the Higuchi Bound
Bordin, Lorenzo; Mirbabayi, Mehrdad; Noreña, Jorge
2016-01-01
We point out that tensor consistency relations-i.e. the behavior of primordial correlation functions in the limit a tensor mode has a small momentum-are more universal than scalar consistency relations. They hold in the presence of multiple scalar fields and as long as anisotropies are diluted exponentially fast. When de Sitter isometries are approximately respected during inflation this is guaranteed by the Higuchi bound, which forbids the existence of light particles with spin: De Sitter space can support scalar hair but no curly hair. We discuss two indirect ways to look for the violation of tensor con- sistency relations in observations, as a signature of models in which inflation is not a strong isotropic attractor, such as solid inflation: (a) Graviton exchange contribution to the scalar four-point function; (b) Quadrupolar anisotropy of the scalar power spectrum due to super-horizon tensor modes. This anisotropy has a well-defined statistics which can be distinguished from cases in which the background...
Directory of Open Access Journals (Sweden)
Lee Shaish
Full Text Available The high morphological resemblance between branching corals and trees, can lead to comparative studies on pattern formation traits, best exemplified in plants and in some cnidarians. Here, 81 branches of similar size of the hermatypic coral Stylophora pistillata were lopped of three different genets, their skeletons marked with alizarin red-S, and divided haphazardly into three morphometric treatment groups: (I upright position; (II horizontal position, intact tip; and (III horizontal position, cut tip. After 1 y of in-situ growth, the 45 surviving ramets were brought to the laboratory, their tissues removed and their architectures analyzed by 22 morphological parameters (MPs. We found that within 1 y, isolated branches developed into small coral colonies by growing new branches from all branch termini, in all directions. No architectural dissimilarity was assigned among the three studied genets of treatment I colonies. However, a major architectural disparity between treatment I colonies and colonies of treatments II and III was documented as the development of mirror structures from both sides of treatments II and III settings as compared to tip-borne architectures in treatment I colonies. We did not observe apical dominance since fragments grew equally from all branch sides without documented dominant polarity along branch axis. In treatment II colonies, no MP for new branches originating either from tips or from branch bases differed significantly. In treatment III colonies, growth from the cut tip areas was significantly lower compared to the base, again, suggesting lack of apical dominance in this species. Changes in branch polarity revealed genet associated plasticity, which in one of the studied genets, led to enhanced growth. Different genets exhibited canalization flexibility of growth patterns towards either lateral growth, or branch axis extension (skeletal weight and not porosity was measured. This study revealed that colony
He Songnian; Liang Xiao-Lan
2010-01-01
Let be a real Hilbert space and let be a boundedly Lipschitzian and strongly monotone operator. We design three hybrid steepest descent algorithms for solving variational inequality of finding a point such that , for all , where is the set of fixed points of a strict pseudocontraction, or the set of common fixed points of finite strict pseudocontractions. Strong convergence of the algorithms is proved.
Kortstee, A.J.
1997-01-01
Starch consists of two major components; amylose and amylopectin. Amylose is synthesized by the enzyme Granule-Bound Starch Syntase (GBSS) and consists of essentially linear chains of α-1,4 linked glucose residues. Amylopectin is synthesized by the combined activity of the enzymes Soluble Starch Synthase (SSS) and Branching enzyme (BE) and consists of linear α-1,4 linked glucosidic chains with α-1,6 linked branchpoints. The amount and fine structure of each of the components determine the sta...
Composition and Structural Features of Calcium—Bound and Iron—and Aluminium—Bound Humus in Soils
Institute of Scientific and Technical Information of China (English)
S．U．CHEEMA; XUJIAN－MIN; 等
1994-01-01
Calcium-bound and iron-and aluminium-bound humus extracted from different soils collected from north to south of China were characterized by chemical and spectroscopic methods.Meaningful differences in the composition and structure between them were revealed by 13 C NMR,visible spectroscopy and elemental analysis.Results showed that the contents of carbon,hydrogen and nitrogen were higher in iron-and aluminium-bound humus than in calcium-bound humus while oxygen content in calcium-bound humus was shown to be higher .The calcium-bound humus had higher C/N and O/C ratios than iron-and aluminiumbound humus.The calcium-bound humic acid(HA1) showed higher E4/E6 ratios than iron-and aluminumboud,humic acid(HA2)while iron-and aluminum-bound fulvic acid(FA2) showed higher E4/E6 ratios than calcium-bound fulvic acid(FA1).An inverse relationship between E4/E6 ratios and aromaticity as determined by 13C NMR spectra was observerd for HA and FA from black soil.The 13C NMR spectroscopy revealed that HA2 was more aromatic than HA1.On the other ,FA1 exhibited a higher aromaticity than FA2.
Classical and quantum partition bound and detector inefficiency
Laplante, S; Roland, J
2012-01-01
In communication complexity, two players each have an input and they wish to compute some function of the joint inputs. This has been the object of much study and a wide variety of lower bound methods have been introduced to address the problem of showing lower bounds on communication. Recently, Jain and Klauck introduced the partition bound, which subsumes many of the known methods, in particular factorization norm, discrepancy, and the rectangle (corruption) bound. Physicists have considered a closely related scenario where two players share a predefined entangled state. Each is given a measurement as input, which they perform on their share of the system. The outcomes of the measurements follow a distribution which is predicted by quantum mechanics. In an experimental setting, Bell inequalities are used to distinguish truly quantum from classical behavior. We present a new lower bound technique based on the notion of detector inefficiency (where some runs are discarded by either of the players) for the ext...
Upper bounds on minimum cardinality of exact and approximate reducts
Chikalov, Igor
2010-01-01
In the paper, we consider the notions of exact and approximate decision reducts for binary decision tables. We present upper bounds on minimum cardinality of exact and approximate reducts depending on the number of rows (objects) in the decision table. We show that the bound for exact reducts is unimprovable in the general case, and the bound for approximate reducts is almost unimprovable in the general case. © 2010 Springer-Verlag Berlin Heidelberg.
Three types of statistics and the entropy bounds
Xiao, Yong; Chen, Yi-Xin
2008-01-01
We investigated the entropy bounds of the three types of statistics: para-Bose, para-Fermi and infinite statistics. We showed that the entropy bounds of the conventional Bose, Fermi statistics and their generalizations to parastatistics obey the $A^{3/4}$ law, while the entropy bound of infinite statistics obeys the area law. This suggests a close relationship between infinite statistics and quantum gravity.
Free compact boson on branched covering of $\\mathbb{CP}^1$ and on branched covering of the torus
Liu, Feihu
2016-01-01
We have studied free compact boson on two special kinds of Riemann surfaces: One is branched covering of $\\mathbb{CP}^1$, and the other one is branched covering of the torus. We obtain the partition function for arbitrary higher genus by directly constructing the period matrix, which can be expressed in terms of simple contour integrals. The partition function is interesting because it is related to the \\emph{product} of correlation functions of twist fields in different sectors. Also, when the branched cuts are chosen to be real, it is related to the R\\'enyi entanglement entropy of multiple intervals in a infinite (finite) system at zero (finite) temperature.
Graphene in inhomogeneous magnetic fields: bound, quasi-bound and scattering states
Energy Technology Data Exchange (ETDEWEB)
Ramezani Masir, M; Peeters, F M [Departement Fysica, Universiteit Antwerpen Groenenborgerlaan 171, B-2020 Antwerpen (Belgium); Vasilopoulos, P, E-mail: mrmphys@gmail.com, E-mail: takis@alcor.concordia.ca, E-mail: francois.peeters@ua.ac.be [Department of Physics, Concordia University, Montreal, Quebec, H4B 1R6 (Canada)
2011-08-10
The electron states in graphene-based magnetic dot and magnetic ring structures and combinations of both are investigated. The corresponding spectra are studied as a function of the radii, the strengths of the inhomogeneous magnetic field and of a uniform background field, the strength of an electrostatic barrier and the angular momentum quantum number. In the absence of an external magnetic field we have only long-lived quasi-bound and scattering states and we assess their influence on the density of states. In addition, we consider elastic electron scattering by a magnetic dot, whose average B vanishes, and show that the Hall and longitudinal resistivities, as a function of the Fermi energy, exhibit a pronounced oscillatory structure due to the presence of quasi-bound states. Depending on the dot parameters this oscillatory structure differs substantially for energies below and above the first Landau level.
3-SAT Faster and Simpler - Unique-SAT Bounds for PPSZ Hold in General
Hertli, Timon
2011-01-01
The PPSZ algorithm by Paturi, Pudl\\'ak, Saks, and Zane [1998] is the fastest known algorithm for Unique k-SAT, where the input formula does not have more than one satisfying assignment. For k>=5 the same bounds hold for general k-SAT. We show that this is also the case for k=3,4, using a slightly modified PPSZ algorithm. We do the analysis by defining a cost for satisfiable CNF formulas, which we prove to decrease in each PPSZ step by a certain amount. This improves our previous best bounds with Moser and Scheder [2011] for 3-SAT from O(1.32065^n) to O(1.30704^n) and for 4-SAT from O(1.46928^n) to O(1.46899^n).
Dippel, O.; Brandl, V.; Bässler, H.; Danieli, R.; Zamboni, R.; Taliani, C.
1993-12-01
The fluorescence yield of thin films of sexithienyl drops rapidly above the S 1←S 0 absorption edge while the yield of photocarrier generation increases simultaneously. This unusual behavior of a molecular solid is interpreted in terms of an energy-dependent branching between fluorescence and dissociation of a singlet excitation into a weakly bound electron—hole pair. This is shown to be a characteristic feature of a disordered system in which the energy levels of both neutral and charged excitations are subject to inhomogeneous broadening. In T6 the latter arises from torsional displacement of the thienylene moities.
ELEMENTARY DENSITY BOUNDS FOR SELF-SIMILAR SETS AND APPLICATION
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
Falconer[1] used the relationship between upper convex density and upper spherical density to obtain elementary density bounds for s-sets at HS-almost all points of the sets. In this paper, following Falconer[1], we first provide a basic method to estimate the lower bounds of these two classes of set densities for the self-similar s-sets satisfying the open set condition (OSC), and then obtain elementary density bounds for such fractals at all of their points. In addition, we apply the main results to the famous classical fractals and get some new density bounds.
A Matrix Hyperbolic Cosine Algorithm and Applications
Zouzias, Anastasios
2011-01-01
Wigderson and Xiao presented an efficient derandomization of the matrix Chernoff bound using the method of pessimistic estimators. Based on their construction, we present a derandomization of the matrix Bernstein inequality which can be viewed as generalization of Spencer's hyperbolic cosine algorithm. We apply our construction to several problems by analyzing its computational efficiency under two special cases of matrix samples; one in which the samples have a group structure and the other in which they have rank-one outer-product structure. As a consequence of the former case, we present a deterministic algorithm that, given the multiplication table of a finite group of size n, constructs an Alon-Roichman expanding Cayley graph of logarithmic degree in O(n^2 log^3 n) time. For the latter case, we present a fast deterministic algorithm for spectral sparsification of positive semi-definite matrices (as defined in [Sri10]) which implies directly an improved deterministic algorithm for spectral graph sparsific...
Microscopic observation of magnon bound states and their dynamics
Fukuhara, Takeshi; Schauß, Peter; Endres, Manuel; Hild, Sebastian; Cheneau, Marc; Bloch, Immanuel; Gross, Christian
2013-01-01
More than eighty years ago, H. Bethe pointed out the existence of bound states of elementary spin waves in one-dimensional quantum magnets. To date, identifying signatures of such magnon bound states has remained a subject of intense theoretical research while their detection has proved challenging for experiments. Ultracold atoms offer an ideal setting to reveal such bound states by tracking the spin dynamics after a local quantum quench with single-spin and single-site resolution. Here we r...
FY 1991 Measurements and Characterization Branch annual report
Energy Technology Data Exchange (ETDEWEB)
Osterwald, C.R.; Dippo, P.C. [eds.
1992-11-01
The Measurements and Characterization Branch of the National Renewable Laboratory (NREL) provides comprehensive photovoltaic (PV) materials, devices, characterization, measurement, fabrication, modeling research, and support for the international PV research community, in the context of the US Department of Energy`s Photovoltaic Research Program goals. This report summarizes the progress of the Branch from 31 January 1991 through 31 January 1992. The eight technical sections present a succinct overview of the capabilities and accomplishments of each group in the Branch. The Branch is comprised of the following groups: Surface and interface Analysis; Materials Characterization; Device Development; Electro-optical Characterization; Advanced PV module Performance and Reliability Research; Cell Performance Characterization; Surface Interactions, Modification, and Stability; and FTIR Spectroscopic Research. The including measurements and tests of PV materials, cells, submodules, and modules. The report contains a comprehensive bibliography of 77 branch originated journal and conference publications, which were authored in collaboration with, or in support of, approximately 135 university, industrial, government, and in-house research groups.
FY 1991 Measurements and Characterization Branch annual report
Energy Technology Data Exchange (ETDEWEB)
Osterwald, C.R.; Dippo, P.C. (eds.)
1992-11-01
The Measurements and Characterization Branch of the National Renewable Laboratory (NREL) provides comprehensive photovoltaic (PV) materials, devices, characterization, measurement, fabrication, modeling research, and support for the international PV research community, in the context of the US Department of Energy's Photovoltaic Research Program goals. This report summarizes the progress of the Branch from 31 January 1991 through 31 January 1992. The eight technical sections present a succinct overview of the capabilities and accomplishments of each group in the Branch. The Branch is comprised of the following groups: Surface and interface Analysis; Materials Characterization; Device Development; Electro-optical Characterization; Advanced PV module Performance and Reliability Research; Cell Performance Characterization; Surface Interactions, Modification, and Stability; and FTIR Spectroscopic Research. The including measurements and tests of PV materials, cells, submodules, and modules. The report contains a comprehensive bibliography of 77 branch originated journal and conference publications, which were authored in collaboration with, or in support of, approximately 135 university, industrial, government, and in-house research groups.
Adams, Gareth; Vick, G. W., III; Bordelon, Cassius; Insull, William; Morrisett, Joel
2002-05-01
A new algorithm for measuring carotid artery volumes and estimating atherosclerotic plaque volumes from MRI images has been developed and validated using pressure-perfusion-fixed cadaveric carotid arteries. Our method uses an active contour algorithm with the generalized gradient vector field force as the external force to localize the boundaries of the artery on each MRI cross-section. Plaque volume is estimated by an automated algorithm based on estimating the normal wall thickness for each branch of the carotid. Triplicate volume measurements were performed by a single observer on thirty-eight pairs of cadaveric carotid arteries. The coefficient of variance (COV) was used to quantify measurement reproducibility. Aggregate volumes were computed for nine contiguous slices bounding the carotid bifurcation. The median (mean +/- SD) COV for the 76 aggregate arterial volumes was 0.93% (1.47% +/- 1.52%) for the lumen volume, 0.95% (1.06% +/- 0.67%) for the total artery volume, and 4.69% (5.39% +/- 3.97%) for the plaque volume. These results indicate that our algorithm provides repeatable measures of arterial volumes and a repeatable estimate of plaque volume of cadaveric carotid specimens through analysis of MRI images. The algorithm also significantly decreases the amount of time necessary to generate these measurements.
Randomized algorithms for matrices and data
Mahoney, Michael W
2011-01-01
Randomized algorithms for very large matrix problems have received a great deal of attention in recent years. Much of this work was motivated by problems in large-scale data analysis. Although this work had its origins within theoretical computer science, where researchers were interested in proving worst-case bounds, i.e., bounds without any assumptions at all on the input data, researchers from numerical linear algebra, statistics, applied mathematics, data analysis, and machine learning, as well as domain scientists have subsequently extended and applied these methods in important ways. Although this has been great for the development of the area and for the technology transfer of theoretical ideas into practical applications, this interdisciplinarity has thus far sometimes obscured the underlying simplicity and generality of the core ideas. This review will provide a detailed overview of recent work on randomized algorithms for matrix problems, with an emphasis on a few simple core ideas that underlie not...
Adaptive path planning: Algorithm and analysis
Energy Technology Data Exchange (ETDEWEB)
Chen, Pang C.
1995-03-01
To address the need for a fast path planner, we present a learning algorithm that improves path planning by using past experience to enhance future performance. The algorithm relies on an existing path planner to provide solutions difficult tasks. From these solutions, an evolving sparse work of useful robot configurations is learned to support faster planning. More generally, the algorithm provides a framework in which a slow but effective planner may be improved both cost-wise and capability-wise by a faster but less effective planner coupled with experience. We analyze algorithm by formalizing the concept of improvability and deriving conditions under which a planner can be improved within the framework. The analysis is based on two stochastic models, one pessimistic (on task complexity), the other randomized (on experience utility). Using these models, we derive quantitative bounds to predict the learning behavior. We use these estimation tools to characterize the situations in which the algorithm is useful and to provide bounds on the training time. In particular, we show how to predict the maximum achievable speedup. Additionally, our analysis techniques are elementary and should be useful for studying other types of probabilistic learning as well.
Size-exclusion chromatography (SEC) of branched polymers and polysaccharides.
Gaborieau, Marianne; Castignolles, Patrice
2011-02-01
Branched polymers are among the most important polymers, ranging from polyolefins to polysaccharides. Branching plays a key role in the chain dynamics. It is thus very important for application properties such as mechanical and adhesive properties and digestibility. It also plays a key role in viscous properties, and thus in the mechanism of the separation of these polymers in size-exclusion chromatography (SEC). Critically reviewing the literature, particularly on SEC of polyolefins, polyacrylates and starch, we discuss common pitfalls but also highlight some unexplored possibilities to characterize branched polymers. The presence of a few long-chain branches has been shown to lead to a poor separation in SEC, as evidenced by multiple-detection SEC or multidimensional liquid chromatography. The local dispersity can be large in that case, and the accuracy of molecular weight determination achieved by current methods is poor, although hydrodynamic volume distributions offer alternatives. In contrast, highly branched polymers do not suffer from this extensive incomplete separation in terms of molecular weight. PMID:20967430
Flow-induced pruning of branched systems and brittle reconfiguration
Lopez, Diego; de Langre, Emmanuel
2011-01-01
Whereas most plants are flexible structures that undergo large deformations under flow, another process can occur when the plant is broken by heavy fluid-loading. We investigate here the mechanism of such possible breakage, focusing on the flow-induced pruning that can be observed in plants or aquatic vegetation when parts of the structure break under flow. By computation on an actual tree geometry, a 20-yr-old walnut tree (Juglans Regia L.) and comparison with simple models, we analyze the influence of geometrical and physical parameters on the occurrence of branch breakage and on the successive breaking events occurring in a tree-like structure when the flow velocity is increased. We show that both the branching pattern and the slenderness exponent, defining the branch taper, play a major role in the breakage scenario. We identify a criterion for branch breakage to occur before breakage of the trunk. In that case, we show that the successive breakage of peripheral branches allows the plant to sustain higher...
Bounded cascade clouds: albedo and effective thickness
Cahalan, R. F.
2002-01-01
If climate models produced clouds having liquid water amounts close to those observed, they would compute a mean albedo that is often much too large, due to the treatment of clouds as plane-parallel. An approximate lower-bound for this "plane-parallel albedo bias" may be obtained from a fractal model having a range of optical thicknesses similar to those observed in marine stratocumulus, since they are more nearly plane-parallel than most other cloud types. We review ...
RADIONUCLIDE INVENTORY AND DISTRIBUTION: FOURMILE BRANCH, PEN BRANCH, AND STEEL CREEK IOUS
Energy Technology Data Exchange (ETDEWEB)
Hiergesell, R.; Phifer, M.
2014-04-29
As a condition to the Department of Energy (DOE) Low Level Waste Disposal Federal Facility Review Group (LFRG) review team approving the Savannah River Site (SRS) Composite Analysis (CA), SRS agreed to follow up on a secondary issue, which consisted of the consolidation of several observations that the team concluded, when evaluated collectively, could potentially impact the integration of the CA results. This report addresses secondary issue observations 4 and 21, which identify the need to improve the CA sensitivity and uncertainty analysis specifically by improving the CA inventory and the estimate of its uncertainty. The purpose of the work described herein was to be responsive to these secondary issue observations by re-examining the radionuclide inventories of the Integrator Operable Units (IOUs), as documented in ERD 2001 and Hiergesell, et. al. 2008. The LFRG concern has been partially addressed already for the Lower Three Runs (LTR) IOU (Hiergesell and Phifer, 2012). The work described in this investigation is a continuation of the effort to address the LFRG concerns by re-examining the radionuclide inventories associated with Fourmile Branch (FMB) IOU, Pen Branch (PB) IOU and Steel Creek (SC) IOU. The overall approach to computing radionuclide inventories for each of the IOUs involved the following components: • Defining contaminated reaches of sediments along the IOU waterways • Identifying separate segments within each IOU waterway to evaluate individually • Computing the volume and mass of contaminated soil associated with each segment, or “compartment” • Obtaining the available and appropriate Sediment and Sediment/Soil analytical results associated with each IOU • Standardizing all radionuclide activity by decay-correcting all sample analytical results from sample date to the current point in time, • Computing representative concentrations for all radionuclides associated with each compartment in each of the IOUs • Computing the
Interactions between auxin and strigolactone in shoot branching control.
Hayward, Alice; Stirnberg, Petra; Beveridge, Christine; Leyser, Ottoline
2009-09-01
In Arabidopsis (Arabidopsis thaliana), the carotenoid cleavage dioxygenases MORE AXILLARY GROWTH3 (MAX3) and MAX4 act together with MAX1 to produce a strigolactone signaling molecule required for the inhibition of axillary bud outgrowth. We show that both MAX3 and MAX4 transcripts are positively auxin regulated in a manner similar to the orthologous genes from pea (Pisum sativum) and rice (Oryza sativa), supporting evolutionary conservation of this regulation in plants. This regulation is important for branching control because large auxin-related reductions in these transcripts are associated with increased axillary branching. Both transcripts are up-regulated in max mutants, and consistent with max mutants having increased auxin in the polar auxin transport stream, this feedback regulation involves auxin signaling. We suggest that both auxin and strigolactone have the capacity to modulate each other's levels and distribution in a dynamic feedback loop required for the coordinated control of axillary branching. PMID:19641034
Decay parameter and related properties of 2-type branching processes
Institute of Scientific and Technical Information of China (English)
LI JunPing
2009-01-01
We consider the decay parameter, invariant measures/vectors and quasi-stationary dis-tributions for 2-type Markov branching processes. Investigating such properties is crucial in realizing life period of branching models. In this paper, some important properties of the generating functions for 2-type Markov branching q-matrix are firstly investigated in detail. The exact value of the decay parameter λC of such model is given for the communicating class C = Z+2\\ 0. It is shown that this λC can be directly obtained from the generating functions of the corresponding q-matrix. Moreover, the λC-invariant measures/vectors and quasi-distributions of such processes are deeply considered. A λC-invariant vector for the q-matrix (or for the process) on C is given and the generating functions of λC-invariant measures and quasi-stationary distributions for the process on C are presented.
Decay parameter and related properties of 2-type branching processes
Institute of Scientific and Technical Information of China (English)
2009-01-01
We consider the decay parameter, invariant measures/vectors and quasi-stationary dis- tributions for 2-type Markov branching processes. Investigating such properties is crucial in realizing life period of branching models. In this paper, some important properties of the generating functions for 2-type Markov branching q-matrix are firstly investigated in detail. The exact value of the decay parameter λC of such model is given for the communicating class C = Z+2 \\ 0. It is shown that this λC can be directly obtained from the generating functions of the corresponding q-matrix. Moreover, the λC-invariant measures/vectors and quasi-distributions of such processes are deeply considered. A λC-invariant vector for the q-matrix (or for the process) on C is given and the generating functions of λC-invariant measures and quasi-stationary distributions for the process on C are presented.
Ground state and excitations of a Bose-Einstein condensate of atoms and their diatomic bound states
International Nuclear Information System (INIS)
We study theoretically a many-body system of spinless atoms and their diatomic bound states (or molecules) which form a single Bose-Einstein condensate at zero temperature. The equilibrium states of such a system and its dynamics are analyzed within the Gross-Pitaevskii approach. It is shown that the system exhibits two phases depending on binding energy value: it can be in the states with atomic-molecular condensate or molecular condensate. The basic thermodynamic characteristics of the two phases and their stability conditions are obtained. Both phases are characterized by two branches of collective excitations. The first branch is acoustic mode and the second one is gapfull
Chen, S.; Al-Muntasheri, G.; Abousleiman, Y. N.
2014-12-01
The critical state concept based bounding surface model is one of the most widely used elastoplastic constitutive models for geomaterials, attributed mainly to its essential feature of allowing plastic deformation to occur for stress points within the bounding surface and thus the capability to represent the realistic non-recoverable behaviour of soils and rocks observed under the cyclic loading. This paper develops an implicit integration algorithm for the bounding surface model, using the standard return mapping approach (elastic predictor-plastic corrector), to obtain the updated stresses for the given strain increments. The formulation of the constitutive integration requires the derivation of a supplementary differential equation to describe the evolution of a key variable, i.e., the ratio between the image stress and the current stress quantities. It is essentially an extension of the integration scheme presented in an earlier work used for the simple bounding surface version of modified Cam Clay associated with a substantially simplified hardening rule. The integration algorithm for the bounding surface model is implemented into the finite element analysis commercial program, ABAQUS, through the material interface of UMAT (user defined material subroutine), and then used for the analysis of wellbore stability problem. The predictions from the ABAQUS simulations are generally in excellent agreement with the available analytical solutions, thus demonstrating the accuracy and robustness of the proposed integration scheme.
Hydrocarbon metabolism by Brevibacterium erythrogenes: normal and branched alkanes.
Pirnik, M P; Atlas, R M; Bartha, R
1974-09-01
Branched- and straight-chain alkanes are metabolized by Brevibacterium erythrogenes by means of two distinct pathways. Normal alkanes (e.g., n-pentadecane) are degraded, after terminal oxidation, by the beta-oxidation system operational in fatty acid catabolism. Branched alkanes like pristane (2,6,10,14-tetramethylpentadecane) and 2-methylundecane are degraded as dicarboxylic acids, which also undergo beta-oxidation. Pristane-derived intermediates are observed to accumulate, with time, as a series of dicarboxylic acids. This dicarboxylic acid pathway is not observed in the presence of normal alkanes. Release of (14)CO(2) from [1-(14)C]pristane is delayed, or entirely inhibited, in the presence of n-hexadecane, whereas CO(2) release from n-hexadecane remains unaffected. These results suggest an inducible dicarboxylic acid pathway for degradation of branched-chain alkanes. PMID:4852318
Approach of generating parallel programs from parallelized algorithm design strategies
Institute of Scientific and Technical Information of China (English)
WAN Jian-yi; LI Xiao-ying
2008-01-01
Today, parallel programming is dominated by message passing libraries, such as message passing interface (MPI). This article intends to simplify parallel programming by generating parallel programs from parallelized algorithm design strategies. It uses skeletons to abstract parallelized algorithm design strategies, as well as parallel architectures. Starting from problem specification, an abstract parallel abstract programming language+ (Apla+) program is generated from parallelized algorithm design strategies and problem-specific function definitions. By combining with parallel architectures, implicity of parallelism inside the parallelized algorithm design strategies is exploited. With implementation and transformation, C++ and parallel virtual machine (CPPVM) parallel program is finally generated. Parallelized branch and bound (B&B) algorithm design strategy and parallelized divide and conquer (D & C) algorithm design strategy are studied in this article as examples. And it also illustrates the approach with a case study.
Li, Xingfeng; Miao, Ming; Jiang, Huan; Xue, Jiangchao; Jiang, Bo; Zhang, Tao; Gao, Yaqi; Jia, Yingmin
2014-12-01
Partial branching enzyme treatment was used to modulate the starch fine chain structure responsible for a high content of slowly digestible starch fraction. Normal maize starch modified using branching enzyme for 4h showed a maximum slowly digestible starch content of 23.90%. The branching enzyme hydrolysis decreased the amylose content from 32.8% to 12.8%. The molecular weight distribution of enzyme-treated starches showed a larger proportion of low molecular weight fractions appeared in the enzyme treated starch sample compare to native starch. The number of shorter chains (DP30) from 20.11% to 11.95%. (1)H NMR spectra showed an increase of α-1,6 branching ratio from 4.7% to 9.4% during enzyme treatment. The increase in the amount of shorter chains and more α-1,6 linkages likely contribute to their slow digestion property. These results suggest that starches treated with partial branching enzyme synthesis a novel branched structure with slowly digestible character.
Parallel Algorithms and Patterns
Energy Technology Data Exchange (ETDEWEB)
Robey, Robert W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-06-16
This is a powerpoint presentation on parallel algorithms and patterns. A parallel algorithm is a well-defined, step-by-step computational procedure that emphasizes concurrency to solve a problem. Examples of problems include: Sorting, searching, optimization, matrix operations. A parallel pattern is a computational step in a sequence of independent, potentially concurrent operations that occurs in diverse scenarios with some frequency. Examples are: Reductions, prefix scans, ghost cell updates. We only touch on parallel patterns in this presentation. It really deserves its own detailed discussion which Gabe Rockefeller would like to develop.
Institutional tensions between the Executive and Legislative branches in Brazil
Directory of Open Access Journals (Sweden)
Margarita JIMÉNEZ BADILLO
2011-06-01
Full Text Available This study attempts to explain the mechanism through which the Brazilian president manages to govern in Brazil amidst a non majority parliamentary scenario with a highly fragmented party system, rising numbers of switchers, an ostensible lack of discipline of the political parties members, and a precarious party coalition. If the Brazilian political system has not yet fallen into an institutional paralysis of governability it is due to the ability of the Executive branch to obtain support from certain parliamentary coalitions and succeeding thereof to outdo actors with veto power, attempting to hinder relations between the Executive and the Legislative branches.
Scale dependence of branching in arterial and bronchial trees
Restrepo, J G; Hunt, B R; Restrepo, Juan G.; Ott, Edward; Hunt, Brian R.
2005-01-01
Although models of branching in arterial and bronchial trees often predict a dependence of bifurcation parameters on the scale of the bifurcating vessels, direct verifications of this dependence with data are uncommon. We compare measurements of bifurcation parameters in airways and arterial trees of different mammals as a function of scale to general features predicted by theoretical models. We find that the size dependence is more complex than existing theories based solely on energy minimization explain, and suggest additional factors that may govern the branching at different scales.
Thulasiraman, K
2011-01-01
This adaptation of an earlier work by the authors is a graduate text and professional reference on the fundamentals of graph theory. It covers the theory of graphs, its applications to computer networks and the theory of graph algorithms. Also includes exercises and an updated bibliography.
Lesson Eleven Transient and intermittent left bundle branch block
Institute of Scientific and Technical Information of China (English)
鲁端; 王劲
2004-01-01
@@ In transient left bundle branch block,normal intraventricular conduction subsequently returns,if only1temporarily.The condition has also been called paroxysmal,unstable,or temporary left bundle branch block. Its etiology is similar to that of the stable variety2, with the great majority of the patients having ischemic or hypertensive heart disease or both. Transient bundle branch block may complicate acute myocardial infarction or may occur during attacks of angina. It may appear during an episode of congestive heart failure and disappear with improvement of the cardiac status. Most patients eventually develop permanent block. Occasionally,however, the patient may revert to normal conduction even years after consistently demonstrating the block.
An Efficient Algorithm for Upper Bound on the Partition Function of Nucleic Acids
Chitsaz, Hamidreza; Forouzmand, Elmirasadat; Haffari, Gholamreza
2013-01-01
It has been shown that minimum free energy structure for RNAs and RNA-RNA interaction is often incorrect due to inaccuracies in the energy parameters and inherent limitations of the energy model. In contrast, ensemble based quantities such as melting temperature and equilibrium concentrations can be more reliably predicted. Even structure prediction by sampling from the ensemble and clustering those structures by Sfold [7] has proven to be more reliable than minimum free energy structure pred...
Person perception and the bounded rationality of social judgment.
Wright, J C; Dawson, V L
1988-11-01
In this article, we develop a bounded rationality view of the relation between person perception and social behavior. Two theses of this approach are that behaviors vary in their significance to observers, and that observers pursue bounded rather than global utility in forming personality impressions. Observers are expected to be sensitive to targets' overall behavioral tendencies and to the variability of their behavior across situations, but both sensitivities are bounded, being greater for behaviors that directly affect observers' outcomes. In two investigations involving extensive hourly and 6-s observations, we examined the bounded utility of people's impressions of personality, demonstrating how impression accuracy is linked to the significance of behaviors. Observers were sensitive to the organization of aggressive behaviors, but less sensitive to the organization of withdrawn behaviors, even when the consistency of those behaviors was comparable. The results clarify the relation between people's inferential shortcomings in laboratory paradigms and the bounded utility of person perception in the natural environment.
Person perception and the bounded rationality of social judgment.
Wright, J C; Dawson, V L
1988-11-01
In this article, we develop a bounded rationality view of the relation between person perception and social behavior. Two theses of this approach are that behaviors vary in their significance to observers, and that observers pursue bounded rather than global utility in forming personality impressions. Observers are expected to be sensitive to targets' overall behavioral tendencies and to the variability of their behavior across situations, but both sensitivities are bounded, being greater for behaviors that directly affect observers' outcomes. In two investigations involving extensive hourly and 6-s observations, we examined the bounded utility of people's impressions of personality, demonstrating how impression accuracy is linked to the significance of behaviors. Observers were sensitive to the organization of aggressive behaviors, but less sensitive to the organization of withdrawn behaviors, even when the consistency of those behaviors was comparable. The results clarify the relation between people's inferential shortcomings in laboratory paradigms and the bounded utility of person perception in the natural environment. PMID:3210145
Ngueveu, Sandra Ulrich; Sareni, Bruno; ROBOAM, xavier
2014-01-01
We consider the problem of water production optimization for autonomous water pumping and desalination units supplied by renewable energy sources, designed to be a viable solution to fresh water scarcity for remote areas. Non-linear gyrators as well as the non-linear efficiency of energy and flow transfers model the mechanical-hydraulic power conversion systems involved. We present a generic formulation and resolution algorithms based on piece-wise bounding and integer linear programming to s...
Quantum CPU and Quantum Algorithm
Wang, An Min
1999-01-01
Making use of an universal quantum network -- QCPU proposed by me\\upcite{My1}, it is obtained that the whole quantum network which can implement some the known quantum algorithms including Deutsch algorithm, quantum Fourier transformation, Shor's algorithm and Grover's algorithm.
Algorithms for Scheduling Weighted Packets with Deadlines in a Bounded Queue
LI Fei
2008-01-01
Motivated by the Quality-of-Service (QoS) buffer management problem, we consider online scheduling of packets with hard deadlines in a finite capacity queue. At any time, a queue can store at most $b \\in \\mathbb Z^+$ packets. Packets arrive over time. Each packet is associated with a non-negative value and an integer deadline. In each time step, only one packet is allowed to be sent. Our objective is to maximize the total value gained by the packets sent by their deadlines in an online manner...
DEFF Research Database (Denmark)
Uchoa, Eduardo; Fukasawa, Ricardo; Lysgaard, Jens;
2008-01-01
This paper presents a robust branch-cut-and-price algorithm for the Capacitated Minimum Spanning Tree Problem (CMST). The variables are associated to q-arbs, a structure that arises from a relaxation of the capacitated prize-collecting arborescence problem in order to make it solvable in pseudo...
DEFF Research Database (Denmark)
Uchoa, Eduardo; Fukasawa, Ricardo; Lysgaard, Jens;
This paper presents a robust branch-cut-and-price algorithm for the Capacitated Minimum Spanning Tree Problem (CMST). The variables are associated to q-arbs, a structure that arises from a relaxation of the capacitated prize-collecting arborescence problem in order to make it solvable in pseudo...
Viscosity bound violation in holographic solids and the viscoelastic response
Alberte, Lasma; Pujolas, Oriol
2016-01-01
We argue that the Kovtun--Son--Starinets (KSS) lower bound on the viscosity to entropy density ratio holds in fluid systems but is violated in solid materials with a non-zero shear elastic modulus. We construct explicit examples of this by applying the standard gauge/gravity duality methods to massive gravity and show that the KSS bound is clearly violated in black brane solutions whenever the massive gravity theories are of solid type. We argue that the physical reason for the bound violation relies on the viscoelastic nature of the mechanical response in these materials. We speculate on whether any real-world materials can violate the bound and discuss a possible generalization of the bound that involves the ratio of the shear elastic modulus to the pressure.
Reconstructing 3D Tree Models Using Motion Capture and Particle Flow
Directory of Open Access Journals (Sweden)
Jie Long
2013-01-01
Full Text Available Recovering tree shape from motion capture data is a first step toward efficient and accurate animation of trees in wind using motion capture data. Existing algorithms for generating models of tree branching structures for image synthesis in computer graphics are not adapted to the unique data set provided by motion capture. We present a method for tree shape reconstruction using particle flow on input data obtained from a passive optical motion capture system. Initial branch tip positions are estimated from averaged and smoothed motion capture data. Branch tips, as particles, are also generated within a bounding space defined by a stack of bounding boxes or a convex hull. The particle flow, starting at branch tips within the bounding volume under forces, creates tree branches. The forces are composed of gravity, internal force, and external force. The resulting shapes are realistic and similar to the original tree crown shape. Several tunable parameters provide control over branch shape and arrangement.
Directory of Open Access Journals (Sweden)
Amélie ePinet
2015-02-01
Full Text Available Plant branching is a key process in the yield elaboration of winter oilseed rape (WOSR. It is also involved in plant tolerance to flower damage because it allows the setting of new fertile inflorescences. Here we characterize the changes in the branching and distribution of the number of pods between primary and secondary inflorescences in response to floral bud clippings. Then we investigate the impacts of the modifications in branching on the biomass allocation and its consequence on the crop productivity (harvest index. These issues were addressed on plants with contrasted architecture and branching potential, using three genotypes (Exocet, Pollen, and Gamin grown under two levels of nitrogen fertilization. Clipping treatments of increasing intensities were applied to either inflorescences or flower buds.We were able to show that restoration of the number of pods after clipping is the main lever for the compensation. Genotypes presented different behaviors in branching and biomass allocation as a function of clipping treatments. The number of fertile ramifications increased for the high intensities of clipping. In particular, the growth of secondary ramifications carried by branches developed before clipping has been observed. The proportions of yield and of number of pods carried by these secondary axes increased and became almost equivalent to the proportion carried by primary inflorescences. In terms of biomass allocation, variations have also been evidenced in the relationship between pod dry mass on a given axis and the number of pods set, while the shoot/root ratio was not modified. The harvest index presented different responses: it decreased after flower buds clipping, while it was maintained after the clipping of the whole inflorescences. The results are discussed relative to their implications regarding the identification of interesting traits to be target in breeding programs in order to improve WOSR tolerance.
Stress-based upper-bound method and convex optimization: case of the Gurson material
Pastor, Franck; Trillat, Malorie; Pastor, Joseph; Loute, Etienne
2006-04-01
A nonlinear interior point method associated with the kinematic theorem of limit analysis is proposed. Associating these two tools enables one to determine an upper bound of the limit loading of a Gurson material structure from the knowledge of the sole yield criterion. We present the main features of the interior point algorithm and an original method providing a rigorous kinematic bound from a stress formulation of the problem. This method is tested by solving in plane strain the problem of a Gurson infinite bar compressed between rough rigid plates. To cite this article: F. Pastor et al., C. R. Mecanique 334 (2006).
Special branches: organic greenhouse production, bulbs, ornamentals and aquaculture
Sukkel, W.; Hommes, M.; Meijer, R.J.M.
2009-01-01
Organic production methods are gaining ground in Dutch specialised production branches. Interest is growing among greenhouse horticulturalists and growers of flower bulbs, ornamentals and mushrooms. In organic horticulture Dutch research is unique in the world in thinking up innovative concepts and
Global Expansion of International Branch Campuses: Managerial and Leadership Challenges
Lane, Jason E.
2011-01-01
In this chapter, the author outlines the growth of international branch campuses (IBCs) over the past fifty years and discusses some of the major management and leadership challenges associated with creating and sustaining IBCs. Part one of the chapter provides a discussion of the global expansion of IBCs. The second part focuses on the…
Cutting Planes for Branch-and-Price Algorithms
DEFF Research Database (Denmark)
Desaulniers, Guy; Desrosiers, Jacques; Spoorendonk, Simon
2011-01-01
This article presents a general framework for formulating cutting planes in the context of column generation for integer programs. Valid inequalities can be derived using the variables of an equivalent compact formulation (i.e., the subproblem variables) or the master problem variables. In the fi...
MYOCARDIAL DEFORMATION AND COMPLETE LEFT BUNDLE BRANCH BLOCK
Directory of Open Access Journals (Sweden)
E. N. Pavlyukova
2015-12-01
Full Text Available Tissue Doppler imaging is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular systolic and diastolic function. Over the last 10 years, myocardial deformation imaging has become possible initially with tissue Doppler , and more recently with myocardial speckle-tracking using 2D echocardiography. Unlike simple tissue velocity measurements, deformation measurements are specific for the region of interest. Strain rate or strain measurements have been used as sensitive indicators for subclinical diseases, and it is the most widely used tool to assess mechanical dyssynchrony. Left bundle branch block is a frequent, etiologically heterogeneous, clinically hostile and diagnostically challenging entity. About 2% of patients underwent cardiac stress testing show stable or intermittent left bundle branch block. Presence of left bundle branch block is associated with a lower and slower diastolic coronary flow velocity especially during hyperemia. Stress echocardiography is the best option for the diagnosis of ischemic heart disease, albeit specificity and sensitivity reduce in patients with left bundle branch block in the territory of left anterior descending artery in presence of initial septum dyskinesia.
Join-Graph Propagation Algorithms
Mateescu, Robert; Kask, Kalev; Gogate, Vibhav; Dechter, Rina
2014-01-01
The paper investigates parameterized approximate message-passing schemes that are based on bounded inference and are inspired by Pearl's belief propagation algorithm (BP). We start with the bounded inference mini-clustering algorithm and then move to the iterative scheme called Iterative Join-Graph Propagation (IJGP), that combines both iteration and bounded inference. Algorithm IJGP belongs to the class of Generalized Belief Propagation algorithms, a framework that allowed connections with a...
Nuclear Science and Technology Branch Report 1975
International Nuclear Information System (INIS)
A summary is given of research activities. These include: nuclear techniques of analysis, nuclear techniques in hydrology, industrial applications of radioisotopes, biological and chemical applications of irradiation, radiation detection and measurement, environmental studies and biophysics and radiation biology. Patent applications and staff of the nuclear science and applications secretariat are listed. (R.L.)
Branched polymers, complex spins and the freezing transition
Correia, J D; Wheater, John F; Correia, Joao D.; Mirza, Behrouz; Wheater, John F.
1997-01-01
We show that by coupling complex three-state systems to branched-polymer like ensembles we can obtain models with gamma-string different from one half. It is also possible to study the interpolation between dynamical and crystalline graphs for these models; we find that only when geometry fluctuations are completely forbidden is there a crystalline phase.
Branch Campus Librarianship with Minimal Infrastructure: Rewards and Challenges
Knickman, Elena; Walton, Kerry
2014-01-01
Delaware County Community College provides library services to its branch campus community members by stationing a librarian at a campus 5 to 20 hours each week, without any more library infrastructure than an Internet-enabled computer on the school network. Faculty and students have reacted favorably to the increased presence of librarians.…
RStorm: Developing and Testing Streaming Algorithms in R
Kaptein, M.C.
2014-01-01
Streaming data, consisting of indefinitely evolving sequences, are becoming ubiquitous in many branches of science and in various applications. Computer scientists have developed streaming applications such as Storm and the S4 distributed stream computing platform1 to deal with data streams. However, in current production packages testing and evaluating streaming algorithms is cumbersome. This paper presents RStorm for the development and evaluation of streaming algorithms analogous to these ...
Roles for auxin, cytokinin, and strigolactone in regulating shoot branching.
Ferguson, Brett J; Beveridge, Christine A
2009-04-01
Many processes have been described in the control of shoot branching. Apical dominance is defined as the control exerted by the shoot tip on the outgrowth of axillary buds, whereas correlative inhibition includes the suppression of growth by other growing buds or shoots. The level, signaling, and/or flow of the plant hormone auxin in stems and buds is thought to be involved in these processes. In addition, RAMOSUS (RMS) branching genes in pea (Pisum sativum) control the synthesis and perception of a long-distance inhibitory branching signal produced in the stem and roots, a strigolactone or product. Auxin treatment affects the expression of RMS genes, but it is unclear whether the RMS network can regulate branching independently of auxin. Here, we explore whether apical dominance and correlative inhibition show independent or additive effects in rms mutant plants. Bud outgrowth and branch lengths are enhanced in decapitated and stem-girdled rms mutants compared with intact control plants. This may relate to an RMS-independent induction of axillary bud outgrowth by these treatments. Correlative inhibition was also apparent in rms mutant plants, again indicating an RMS-independent component. Treatments giving reductions in RMS1 and RMS5 gene expression, auxin transport, and auxin level in the main stem were not always sufficient to promote bud outgrowth. We suggest that this may relate to a failure to induce the expression of cytokinin biosynthesis genes, which always correlated with bud outgrowth in our treatments. We present a new model that accounts for apical dominance, correlative inhibition, RMS gene action, and auxin and cytokinin and their interactions in controlling the progression of buds through different control points from dormancy to sustained growth. PMID:19218361
Polyphosphazene Based Star-Branched and Dendritic Molecular Brushes
Henke, Helena; Posch, Sandra; Brüggemann, Oliver; Teasdale, Ian
2016-01-01
A new synthetic procedure is described for the preparation of poly(organo)phosphazenes with star-branched and star dendritic molecular brush type structures, thus describing the first time it has been possible to prepare controlled, highly branched architectures for this type of polymer. Furthermore, as a result of the extremely high-arm density generated by the phosphazene repeat unit, the second-generation structures represent quite unique architectures for any type of polymer. Using two relativity straight forward iterative syntheses it is possible to prepare globular highly branched polymers with up to 30 000 functional end groups, while keeping relatively narrow polydispersities (1.2–1.6). Phosphine mediated polymerization of chlorophosphoranimine is first used to prepare three-arm star polymers. Subsequent substitution with diphenylphosphine moieties gives poly(organo)phosphazenes to function as multifunctional macroinitiators for the growth of a second generation of polyphosphazene arms. Macrosubstitution with Jeffamine oligomers gives a series of large, water soluble branched macromolecules with high-arm density and hydrodynamic diameters between 10 and 70 nm. PMID:27027404
Institute of Scientific and Technical Information of China (English)
陈珍平; 宋婧; 吴斌; 郝丽娟; 胡丽琴; 孙光耀
2016-01-01
Geometry navigation plays the most fundamental role in Monte Carlo particle transport simulation. It’s mainly responsible for locating a particle inside which geometry volume it is and computing the distance to the volume boundary along the certain particle traj ectory during each particle history. Geometry navigation directly affects the run-time performance of the Monte Carlo particle transport simulation, especially for complicated fusion reactor models. Thus, two CAD-based geometry acceleration algorithms,the neighbor search and the bounding box,are presented for improving geometry navigation performance. The algorithms have been implemented in the Super Monte Carlo Simulation Program for Nuclear and Radiation Process (SuperMC). The fusion reactors of FDS-Ⅱ and ITER benchmark models have been tested to highlight the efficiency gains that can be achieved by using the acceleration algorithms. Testing results showed that efficiency of Monte Carlo simulation can be considerably enhanced by 50% to 60% with the acceleration algorithms.%几何跟踪主要进行蒙特卡罗粒子输运计算中粒子位置和径迹长度的计算，它是蒙特卡罗粒子输运计算的关键技术之一。由于聚变堆几何结构极其复杂，使得几何跟踪在整个蒙特卡罗粒子输运计算中占据30％~80％的计算时间，因此几何跟踪方法的效率是决定聚变堆蒙特卡罗粒子输运计算效率的重要因素之一。本文提出了基于CAD的邻居列表和包围盒加速方法，并基于 FDS 团队自主研发的超级蒙特卡罗核计算仿真软件系统 SuperMC进行实现。利用聚变堆 FDS-Ⅱ和 ITER模型对本文方法进行了数值验证，测试结果表明本文方法不影响计算结果，并能使程序计算效率提高50％~60％，证明了本文方法的正确性和有效性。
Nanocrystals with linear and branched topology
Alivisatos, A. Paul; Milliron, Delia; Manna, Liberato; Hughes, Steven M.
2007-12-04
Disclosed herein are nanostructures comprising distinct dots and rods coupled through potential barriers of tuneable height and width, and arranged in three dimensional space at well defined angles and distances. Such control allows investigation of potential applications ranging from quantum information processing to artificial photosynthesis.
Nuclear Science and Technology Branch report 1977
International Nuclear Information System (INIS)
A report of research programs continuing in the following areas is presented: mining and treatment of uranium ores, manufacture of uranium hexafluoride, uranium enrichment, waste treatment, reprocessing and the uranium fuel cycle. Staff responsible for each project are indicated
Nuclear Science and Technology Branch report 1977
International Nuclear Information System (INIS)
This report records the technical service provided in support of research programs at the Research Establishment. Such services include HIFAR reactor operations, engineering services, information services, safety services and services provided research divisions themselves. Radioisotope production and other commercial activities are also included
Nuclear science and technology branch report 1975
International Nuclear Information System (INIS)
Research programs are reported for the following divisions: Engineering Research, Chemical Technology, Instrumentation and Control, Materials division, Isotopes, Physics, Health Physics, Applied Mathematics and Computing, Radiation Biology Research. The names of staff responsible for each project are indicated. (R.L.)
Adaptive delta management: Roots and branches
Timmermans, J.S.; Haasnoot, M.; Hermans, L.M.; Kwakkel, J.H.; Rutten, M.M.; Thissen, W.A.H.
2015-01-01
Deltas are generally recognized as vulnerable to climate change and therefore a salient topic in adaptation science. Deltas are also highly dynamic systems viewed from physical (erosion, sedimentation, subsidence), social (demographic), economic (trade), infrastructures (transport, energy, metropoli
Generic Lower Bounds for Root Extraction and Signature Schemes in General Groups
DEFF Research Database (Denmark)
Damgård, Ivan Bjerre; Koprowski, Maciej
2002-01-01
We study the problem of root extraction in finite Abelian groups, where the group order is unknown. This is a natural generalization of the problem of decrypting RSA ciphertexts. We study the complexity of this problem for generic algorithms, that is, algorithms that work for any group and do not...... use any special properties of the group at hand. We prove an exponential lower bound on the generic complexity of root extraction, even if the algorithm can choose the public exponent itself. In other words, both the standard and the strong RSA assumption are provably true w.r.t. generic algorithms...... implement it in RSA groups without the original restriction that the modulus must be a product of safe primes. It can also be implemented in class groups. In all cases, security follows from a well defined complexity assumption (the strong root assumption), without relying on random oracles, and the...
Boosting foundations and algorithms
Schapire, Robert E
2012-01-01
Boosting is an approach to machine learning based on the idea of creating a highly accurate predictor by combining many weak and inaccurate "rules of thumb." A remarkably rich theory has evolved around boosting, with connections to a range of topics, including statistics, game theory, convex optimization, and information geometry. Boosting algorithms have also enjoyed practical success in such fields as biology, vision, and speech processing. At various times in its history, boosting has been perceived as mysterious, controversial, even paradoxical.
Rigorous Performance Bounds for Quadratic and Nested Dynamical Decoupling
Xia, Yuhou; Lidar, Daniel A
2011-01-01
We present rigorous performance bounds for the quadratic dynamical decoupling (QDD) pulse sequence which protects a qubit from general decoherence, and for its nested generalization to an arbitrary number of qubits. Our bounds apply under the assumption of instantaneous pulses and of bounded perturbing environment and qubit-environment Hamiltonians such as those realized by baths of nuclear spins in quantum dots. We prove that if the total sequence time is fixed then the trace-norm distance between the unperturbed and protected system states can be made arbitrarily small by increasing the number of applied pulses.
Institute of Scientific and Technical Information of China (English)
周莹
2014-01-01
针对Bounding Box算法定位误差大、覆盖率低的缺点，提出了一种采用虚拟锚节点策略的改进定位算法。首先未知节点利用其通信范围内的锚节点进行定位；其次，已定位的节点根据升级策略有选择性的升级为虚拟锚节点；最后，无法定位的节点利用虚拟锚节点实现定位。另外，在离散网络模型的基础上，通过建立双半径网络节点模型从而进一步约束了未知节点的位置。理论分析及仿真结果均表明，该算法在显著提高定位覆盖率的同时，有效地提高了定位精度。%To overcome the disadvantages of localization accuracy and low coverage rate in current Bounding Box al-gorithm,an improved algorithm using the virtual anchor nodes was proposed. Firstly, the anchor nodes within the communication range of unknown nodes were used to calculate the coordinates of the unknown nodes. Secondly,the located unknown nodes were upgraded as the virtual anchor nodes according to the promotion strategy selectively. Finally,the nodes which were unable to locate themselves used the virtual anchor nodes to get their location. On the other hands,the network node model of double radius based on the discrete network model was introduced to restrict the location of the unknown nodes. The result of simulation and analysis shows that the proposed algorithm can improve the localization coverage rate as well as the estimation accuracy significantly.
Valence-bound and diffuse-bound anions of 5-azauracil.
Corzo, H H; Dolgounitcheva, O; Zakrzewski, V G; Ortiz, J V
2014-08-28
Structures, isomerization energies, and electron binding energies of 5-azauracil and its anions have been calculated ab initio with perturbative, coupled-cluster, and electron-propagator methods. Tautomeric structures, including those produced by proton transfer to a CH group, have been considered. Dyson orbitals and pole strengths from electron-propagator calculations validated a simple, molecular-orbital picture of anion formation. In one case, an electron may enter a delocalized π orbital, yielding a valence-bound (VB) anion with a puckered ring structure. The corresponding electron affinity is 0.27 eV; the vertical electron detachment energy (VEDE) of this anion 1.05 eV. An electron also may enter a molecular orbital that lies outside the nuclear framework, resulting in a diffuse-bound (DB) anion. In the latter case, the electron affinity is 0.06 eV and the VEDE of the DB anion is 0.09 eV. Another VB isomer that is only 0.02 eV more stable than the neutral molecule has a VEDE of 2.0 eV. PMID:25102270
Complete manifolds with bounded curvature and spectral gaps
Schoen, Richard; Tran, Hung
2016-08-01
We study the spectrum of complete noncompact manifolds with bounded curvature and positive injectivity radius. We give general conditions which imply that their essential spectrum has an arbitrarily large finite number of gaps. In particular, for any noncompact covering of a compact manifold, there is a metric on the base so that the lifted metric has an arbitrarily large finite number of gaps in its essential spectrum. Also, for any complete noncompact manifold with bounded curvature and positive injectivity radius we construct a metric uniformly equivalent to the given one (also of bounded curvature and positive injectivity radius) with an arbitrarily large finite number of gaps in its essential spectrum.
Institute of Scientific and Technical Information of China (English)
孙光甦
2012-01-01
This paper investigates second-order consensus of multi-agent systems with a virtual leader of varying velocity while preserving network connectivity.We propose a novel second-order consensus algorithm with bounded control inputs.Under the condition that the initial network is connected,the network will be connected all the time and all agents and the virtual leader can attain the same position and move with the same velocity.A simulation example is proposed to illustrate the effective of the proposed algorithm.
Energy Technology Data Exchange (ETDEWEB)
Symbalisty, E.M.D.; Zinn, J.; Whitaker, R.W.
1995-09-01
This paper describes the history, physics, and algorithms of the computer code RADFLO and its extension HYCHEM. RADFLO is a one-dimensional, radiation-transport hydrodynamics code that is used to compute early-time fireball behavior for low-altitude nuclear bursts. The primary use of the code is the prediction of optical signals produced by nuclear explosions. It has also been used to predict thermal and hydrodynamic effects that are used for vulnerability and lethality applications. Another closely related code, HYCHEM, is an extension of RADFLO which includes the effects of nonequilibrium chemistry. Some examples of numerical results will be shown, along with scaling expressions derived from those results. We describe new computations of the structures and luminosities of steady-state shock waves and radiative thermal waves, which have been extended to cover a range of ambient air densities for high-altitude applications. We also describe recent modifications of the codes to use a one-dimensional analog of the CAVEAT fluid-dynamics algorithm in place of the former standard Richtmyer-von Neumann algorithm.
Affinity- and topology-dependent bound on current fluctuations
Pietzonka, Patrick; Seifert, Udo
2016-01-01
We provide a proof of a recently conjectured universal bound on current fluctuations in Markovian processes. This bound establishes a link between the fluctuations of an individual observable current, the cycle affinities driving the system into a non-equilibrium steady state, and the topology of the network. The proof is based on a decomposition of the network into independent cycles with both positive affinity and positive stationary cycle current. This formalism allows for a refinement of the bound for systems in equilibrium or with locally vanishing affinities.
Vulnerable Derivatives and Good Deal Bounds: A Structural Model
DEFF Research Database (Denmark)
Murgoci, Agatha
2013-01-01
a new restriction in the arbitrage free model by setting upper bounds on the Sharpe ratios (SRs) of the assets. The potential prices that are eliminated represent unreasonably good deals. The constraint on the SR translates into a constraint on the stochastic discount factor. Thus, tight pricing bounds...... can be obtained. We provide a link between the objective probability measure and the range of potential risk-neutral measures, which has an intuitive economic meaning. We also provide tight pricing bounds for European calls and show how to extend the call formula to pricing other financial products...
Hodograph computation and bound estimation for rational B-spline curves
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
It is necessary to compute the derivative and estimate the bound of rational B-spline curves in design system, which has not been studied to date. To improve the function of computer aided design (CAD) system, and to enhance the efficiency of different algorithms of rational B-spline curves, the representation of scaled hodograph and bound of derivative magnitude of uniform planar rational B-spline curves are derived by applying Dir function, which indicates the direction of Cartesian vector between homogeneous points, discrete B-spline theory and the formula of translating the product into a summation of B-spline functions. As an application of the result above,upper bound of parametric distance between any two points in a uniform planar rational B-spline curve is further presented.
A New Global Optimization Algorithm for Solving a Class of Nonconvex Programming Problems
Directory of Open Access Journals (Sweden)
Xue-Gang Zhou
2014-01-01
Full Text Available A new two-part parametric linearization technique is proposed globally to a class of nonconvex programming problems (NPP. Firstly, a two-part parametric linearization method is adopted to construct the underestimator of objective and constraint functions, by utilizing a transformation and a parametric linear upper bounding function (LUBF and a linear lower bounding function (LLBF of a natural logarithm function and an exponential function with e as the base, respectively. Then, a sequence of relaxation lower linear programming problems, which are embedded in a branch-and-bound algorithm, are derived in an initial nonconvex programming problem. The proposed algorithm is converged to global optimal solution by means of a subsequent solution to a series of linear programming problems. Finally, some examples are given to illustrate the feasibility of the presented algorithm.
Institute of Scientific and Technical Information of China (English)
WANG ShunJin; ZHANG Hua
2007-01-01
Based on the exact analytical solution of ordinary differential equations,a truncation of the Taylor series of the exact solution to the Nth order leads to the Nth order algebraic dynamics algorithm.A detailed numerical comparison is presented with Runge-Kutta algorithm and symplectic geometric algorithm for 12 test models.The results show that the algebraic dynamics algorithm can better preserve both geometrical and dynamical fidelity of a dynamical system at a controllable precision,and it can solve the problem of algorithm-induced dissipation for the Runge-Kutta algorithm and the problem of algorithm-induced phase shift for the symplectic geometric algorithm.
Institute of Scientific and Technical Information of China (English)
2007-01-01
Based on the exact analytical solution of ordinary differential equations, a truncation of the Taylor series of the exact solution to the Nth order leads to the Nth order algebraic dynamics algorithm. A detailed numerical comparison is presented with Runge-Kutta algorithm and symplectic geometric algorithm for 12 test models. The results show that the algebraic dynamics algorithm can better preserve both geometrical and dynamical fidelity of a dynamical system at a controllable precision, and it can solve the problem of algorithm-induced dissipation for the Runge-Kutta algorithm and the problem of algorithm-induced phase shift for the symplectic geometric algorithm.
Ratkanthwar, Kedar
2013-01-01
An exact comb polyisoprene (PI) with three branches, with the middle branch having twice the molecular weight of the two other identical external branches, was synthesized by using anionic polymerization high vacuum techniques and appropriate chlorosilane chemistry. The synthetic approach involves (a) the selective replacement of the two chlorines of 4-(dichloromethylsilyl) diphenylethylene (DCMSDPE, key molecule) with identical PI chains by titration with PILi, (b) the addition of sec-BuLi to the double bond of DPE followed by the polymerization of isoprene from the newly created anionic site to form a 3-arm living star PI, (c) the selective replacement of the two chlorines of trichloromethylsilane with 3-arm star PI to form an H-shape intermediate, and (d) the replacement of the remaining chlorine of trichloromethylsilane by linear PI chains with double the molecular weight. All intermediate and final products were characterized via size exclusion chromatography, temperature gradient interaction chromatography and 1H-NMR spectroscopy. As expected, due to the inability to control the exact stoichiometry of the linking reactants, the main product (exact comb PI) is contaminated by a few by-products, despite the fact that anionic polymerization is the most efficient way to produce well-defined polymers. © 2013 The Royal Society of Chemistry.
International Nuclear Information System (INIS)
HiggsBounds 2.0.0 is a computer code which tests both neutral and charged Higgs sectors of arbitrary models against the current exclusion bounds from the Higgs searches at LEP and the Tevatron. As input, it requires a selection of model predictions, such as Higgs masses, branching ratios, effective couplings and total decay widths. HiggsBounds 2.0.0 then uses the expected and observed topological cross section limits from the Higgs searches to determine whether a given parameter scenario of a model is excluded at the 95% C.L. by those searches. Version 2.0.0 represents a significant extension of the code since its first release (1.0.0). It includes now 28/53 LEP/Tevatron Higgs search analyses, compared to the 11/22 in the first release, of which many of the ones from the Tevatron are replaced by updates. As a major extension, the code allows now the predictions for (singly) charged Higgs bosons to be confronted with LEP and Tevatron searches. Furthermore, the newly included analyses contain LEP searches for neutral Higgs bosons (H) decaying invisibly or into (non flavour tagged) hadrons as well as decay-mode independent searches for neutral Higgs bosons, LEP searches via the production modes τ+τ-H and b anti bH, and Tevatron searches via t anti tH. Also, all Tevatron results presented at the ICHEP'10 are included in version 2.0.0. As physics applications of HiggsBounds 2.0.0 we study the allowed Higgs mass range for model scenarios with invisible Higgs decays and we obtain exclusion results for the scalar sector of the Randall-Sundrum model using up-to-date LEP and Tevatron direct search results. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Bechtle, P.; Weiglein, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Brein, O. [Freiburg Univ. (Germany). Physikalisches Inst.; Heinemeyer, S. [Instituto de Fisica de Cantabria (CSIC-UC), Santander (Spain); Williams, K.E. [Bonn Univ. (Germany). Bethe Center for Theoretical Physics
2011-03-15
HiggsBounds 2.0.0 is a computer code which tests both neutral and charged Higgs sectors of arbitrary models against the current exclusion bounds from the Higgs searches at LEP and the Tevatron. As input, it requires a selection of model predictions, such as Higgs masses, branching ratios, effective couplings and total decay widths. HiggsBounds 2.0.0 then uses the expected and observed topological cross section limits from the Higgs searches to determine whether a given parameter scenario of a model is excluded at the 95% C.L. by those searches. Version 2.0.0 represents a significant extension of the code since its first release (1.0.0). It includes now 28/53 LEP/Tevatron Higgs search analyses, compared to the 11/22 in the first release, of which many of the ones from the Tevatron are replaced by updates. As a major extension, the code allows now the predictions for (singly) charged Higgs bosons to be confronted with LEP and Tevatron searches. Furthermore, the newly included analyses contain LEP searches for neutral Higgs bosons (H) decaying invisibly or into (non flavour tagged) hadrons as well as decay-mode independent searches for neutral Higgs bosons, LEP searches via the production modes {tau}{sup +}{tau}{sup -}H and b anti bH, and Tevatron searches via t anti tH. Also, all Tevatron results presented at the ICHEP'10 are included in version 2.0.0. As physics applications of HiggsBounds 2.0.0 we study the allowed Higgs mass range for model scenarios with invisible Higgs decays and we obtain exclusion results for the scalar sector of the Randall-Sundrum model using up-to-date LEP and Tevatron direct search results. (orig.)
SENSITIVITY ANALYSIS OF THE KNAPSACK PROBLEM: TIGHTER LOWER AND UPPER BOUND LIMITS
Institute of Scientific and Technical Information of China (English)
Tarik BELGACEM; Mhand HIFI
2008-01-01
In this paper, we study the sensitivity of the optimum of the knapsack problem to the perturbation of the profit of a subset of items. We propose a polynomial heuristic in order to establish both lower and upper bound limits of the sensitivity interval. The aim is to stabilize any given optimal solution obtained by applying any exact algorithm. We then evaluate the effectiveness of the proposed solution procedure on an example and a set of randomly generated problem instances.
Genetic Algorithms and Local Search
Whitley, Darrell
1996-01-01
The first part of this presentation is a tutorial level introduction to the principles of genetic search and models of simple genetic algorithms. The second half covers the combination of genetic algorithms with local search methods to produce hybrid genetic algorithms. Hybrid algorithms can be modeled within the existing theoretical framework developed for simple genetic algorithms. An application of a hybrid to geometric model matching is given. The hybrid algorithm yields results that improve on the current state-of-the-art for this problem.
Balanced distribution-energy inequalities and related entropy bounds
Rumin, Michel
2010-01-01
Let $A$ be a self-adjoint operator acting over a space $X$ endowed with a partition. We give lower bounds on the energy of a mixed state $\\rho$ from its distribution in the partition and the spectral density of $A$. These bounds improve with the refinement of the partition, and generalize inequalities by Li-Yau and Lieb--Thirring for the Laplacian in $\\R^n$. They imply an uncertainty principle, giving a lower bound on the sum of the spatial entropy of $\\rho$, as seen from $X$, and some spectral entropy, with respect to its energy distribution. On $\\R^n$, this yields lower bounds on the sum of the entropy of the densities of $\\rho$ and its Fourier transform. A general log-Sobolev inequality is also shown. It holds on mixed states, without Markovian or positivity assumption on $A$.
US Forest Service Survey parcels described by metes and bounds
US Forest Service, Department of Agriculture — A map service on the www depicting survey parcels described by a metes and bounds description. Examples include: land lots, housing subdivision lots, mineral...
Bounded solutions for fuzzy differential and integral equations
Energy Technology Data Exchange (ETDEWEB)
Nieto, Juan J. [Departamento de Analisis Matematico Facultad de Matematicas Universidad de Santiago de Compostela, 15782 (Spain)] e-mail: amnieto@usc.es; Rodriguez-Lopez, Rosana [Departamento de Analisis Matematico Facultad de Matematicas Universidad de Santiago de Compostela, 15782 (Spain)] e-mail: amrosana@usc.es
2006-03-01
We find sufficient conditions for the boundness of every solution of first-order fuzzy differential equations as well as certain fuzzy integral equations. Our results are based on several theorems concerning crisp differential and integral inequalities.
Agriculture and Food Processes Branch program summary document
Energy Technology Data Exchange (ETDEWEB)
None
1980-06-01
The work of the Agriculture and Food Processes Branch within the US DOE's Office of Industrial Programs is discussed and reviewed. The Branch is responsible for assisting the food and agricultural sectors of the economy in increasing their energy efficiency by cost sharing with industry the development and demonstration of technologies industry by itself would not develop because of a greater than normal risk factor, but have significant energy conservation benefits. This task is made more difficult by the diversity of agriculture and the food industry. The focus of the program is now on the development and demonstration of energy conservation technology in high energy use industry sectors and agricultural functions (e.g., sugar processing, meat processing, irrigation, and crop drying, high energy use functions common to many sectors of the food industry (e.g., refrigeration, drying, and evaporation), and innovative concepts (e.g., energy integrated farm systems. Specific projects within the program are summarized. (LCL)
Random hypergraphs and algorithmics
Andriamampianina, Tsiriniaina
2008-01-01
Hypergraphs are structures that can be decomposed or described; in other words they are recursively countable. Here, we get exact and asymptotic enumeration results on hypergraphs by mean of exponential generating functions. The number of hypergraph component is bounded, as a generalisation of Wright inequalities for graphs: the proof is a combinatorial understanding of the structure by inclusion exclusion. Asymptotic results are obtained, thanks to generating functions proofs are at the end very easy to read, through complex analysis by saddle point method. By this way, we characterized: - the components with a given number of vertices and of hyperedges by the expected size of a random hypermatching in these structures. - the random hypergraphs (evolving hyperedge by hyperedge) according to the expected number of hyperedges when the first cycle appears in the evolving structure. This work is an open road to further works on random hypergraphs such as threshold phenomenon, tools used here seem to be sufficien...
Quantifying Bounded Rationality: Managerial Behaviour and the Smith Predictor
Riddalls, C.E.; Bennett, S.
2001-01-01
The concept of bounded rationality in decision making and research on its relegation to aggregate system dynamics is examined. By recasting one such example of a dynamic system, the Beer Game, as a Smith predictor control system is derived. A stability analysis is then employed to support the and qualify the assertion that the level of bounded rationality can adversely affect the aggregate dynamic behaviour of such supply chains. The analytical basis of these calculations enables the qualific...
Rivera, J. M.; Simpson, R. W.
1980-01-01
The aerial relay system network design problem is discussed. A generalized branch and bound based algorithm is developed which can consider a variety of optimization criteria, such as minimum passenger travel time and minimum liner and feeder operating costs. The algorithm, although efficient, is basically useful for small size networks, due to its nature of exponentially increasing computation time with the number of variables.
Alternation-Trading Proofs, Linear Programming, and Lower Bounds
Williams, Ryan
2010-01-01
A fertile area of recent research has demonstrated concrete polynomial time lower bounds for solving natural hard problems on restricted computational models. Among these problems are Satisfiability, Vertex Cover, Hamilton Path, Mod6-SAT, Majority-of-Majority-SAT, and Tautologies, to name a few. The proofs of these lower bounds follow a certain proof-by-contradiction strategy that we call alternation-trading. An important open problem is to determine how powerful such proofs can possibly be. We propose a methodology for studying these proofs that makes them amenable to both formal analysis and automated theorem proving. We prove that the search for better lower bounds can often be turned into a problem of solving a large series of linear programming instances. Implementing a small-scale theorem prover based on this result, we extract new human-readable time lower bounds for several problems. This framework can also be used to prove concrete limitations on the current techniques.
Higgs interchange and bound states of superheavy fermions
Indian Academy of Sciences (India)
M De Sanctis
2013-09-01
Hypothetical superheavy fourth-generation fermions with a very small coupling with the rest of the Standard Model can give rise to long enough lived bound states. The production and the detection of these bound states would be experimentally feasible at the LHC. Extending, in the present study, the analysis of other authors, a semirelativistic wave equation is solved using an accurate numerical method to determine the binding energies of these possible superheavy fermion-bound states. The interaction given by the Yukawa potential of the Higgs boson exchange is considered; the corresponding relativistic corrections are calculated by means of a model based on the covariance properties of the Hamiltonian. We study the effects given by the Coulomb force. Moreover, we calculate the contributions given by the Coulombic and confining terms of the strong interaction in the case of superheavy quark bound states. The results of the model are critically analysed.
Zhou, Hui; Kunz, Thomas; Schwartz, Howard
2011-01-01
Traditional oscillators used in timing modules of CDMA and WiMAX base stations are large and expensive. Applying cheaper and smaller, albeit more inaccurate, oscillators in timing modules is an interesting research challenge. An adaptive control algorithm is presented to enhance the oscillators to meet the requirements of base stations during holdover mode. An oscillator frequency stability model is developed for the adaptive control algorithm. This model takes into account the control loop which creates the correction signal when the timing module is in locked mode. A recursive prediction error method is used to identify the system model parameters. Simulation results show that an oscillator enhanced by our adaptive control algorithm improves the oscillator performance significantly, compared with uncorrected oscillators. Our results also show the benefit of explicitly modeling the control loop. Finally, the cumulative time error upper bound of such enhanced oscillators is investigated analytically and comparison results between the analytical and simulated upper bound are provided. The results show that the analytical upper bound can serve as a practical guide for system designers. PMID:21244973
Zhou, Hui; Kunz, Thomas; Schwartz, Howard
2011-01-01
Traditional oscillators used in timing modules of CDMA and WiMAX base stations are large and expensive. Applying cheaper and smaller, albeit more inaccurate, oscillators in timing modules is an interesting research challenge. An adaptive control algorithm is presented to enhance the oscillators to meet the requirements of base stations during holdover mode. An oscillator frequency stability model is developed for the adaptive control algorithm. This model takes into account the control loop which creates the correction signal when the timing module is in locked mode. A recursive prediction error method is used to identify the system model parameters. Simulation results show that an oscillator enhanced by our adaptive control algorithm improves the oscillator performance significantly, compared with uncorrected oscillators. Our results also show the benefit of explicitly modeling the control loop. Finally, the cumulative time error upper bound of such enhanced oscillators is investigated analytically and comparison results between the analytical and simulated upper bound are provided. The results show that the analytical upper bound can serve as a practical guide for system designers.
Cosmological stability bound in massive gravity and bigravity
Energy Technology Data Exchange (ETDEWEB)
Fasiello, Matteo; Tolley, Andrew J., E-mail: matte@case.edu, E-mail: andrew.j.tolley@case.edu [CERCA, Department of Physics, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106 (United States)
2013-12-01
We give a simple derivation of a cosmological bound on the graviton mass for spatially flat FRW solutions in massive gravity with an FRW reference metric and for bigravity theories. This bound comes from the requirement that the kinetic term of the helicity zero mode of the graviton is positive definite. The bound is dependent only on the parameters in the massive gravity potential and the Hubble expansion rate for the two metrics. We derive the decoupling limit of bigravity and FRW massive gravity, and use this to give an independent derivation of the cosmological bound. We recover our previous results that the tension between satisfying the Friedmann equation and the cosmological bound is sufficient to rule out all observationally relevant FRW solutions for massive gravity with an FRW reference metric. In contrast, in bigravity this tension is resolved due to different nature of the Vainshtein mechanism. We find that in bigravity theories there exists an FRW solution with late-time self-acceleration for which the kinetic terms for the helicity-2, helicity-1 and helicity-0 are generically nonzero and positive making this a compelling candidate for a model of cosmic acceleration. We confirm that the generalized bound is saturated for the candidate partially massless (bi)gravity theories but the existence of helicity-1/helicity-0 interactions implies the absence of the conjectured partially massless symmetry for both massive gravity and bigravity.
A branch-and-cut-and-price approach for the pickup and delivery problem with shuttle routes
DEFF Research Database (Denmark)
Masson, Renaud; Røpke, Stefan; Lehuédé, Fabien;
2014-01-01
for the PDPS and a branch-and-cut-and-price algorithm to solve it. The pricing sub-problem, an Elementary Shortest Path Problem with Resource Constraints (ESPPRC), is solved with a labeling algorithm enhanced with efficient dominance rules. Three families of valid inequalities are used to strengthen...... the quality of linear relaxations. The method is evaluated on generated and real-world instances containing up to 193 transportation requests. Instances with up to 87 customers are solved to optimality within a computation time of one hour....
Genetic Algorithms and Quantum Computation
Giraldi, Gilson A.; Portugal, Renato; Thess, Ricardo N.
2004-01-01
Recently, researchers have applied genetic algorithms (GAs) to address some problems in quantum computation. Also, there has been some works in the designing of genetic algorithms based on quantum theoretical concepts and techniques. The so called Quantum Evolutionary Programming has two major sub-areas: Quantum Inspired Genetic Algorithms (QIGAs) and Quantum Genetic Algorithms (QGAs). The former adopts qubit chromosomes as representations and employs quantum gates for the search of the best ...
Combinatorial optimization algorithms and complexity
Papadimitriou, Christos H
1998-01-01
This clearly written, mathematically rigorous text includes a novel algorithmic exposition of the simplex method and also discusses the Soviet ellipsoid algorithm for linear programming; efficient algorithms for network flow, matching, spanning trees, and matroids; the theory of NP-complete problems; approximation algorithms, local search heuristics for NP-complete problems, more. All chapters are supplemented by thought-provoking problems. A useful work for graduate-level students with backgrounds in computer science, operations research, and electrical engineering.
Brachial plexus variations in its formation and main branches
Valéria Paula Sassoli Fazan; André de Souza Amadeu; Adilson L. Caleffi; Omar Andrade Rodrigues Filho
2003-01-01
PURPOSE: The brachial plexus has a complex anatomical structure since its origin in the neck throughout its course in the axillary region. It also has close relationship to important anatomic structures what makes it an easy target of a sort of variations and provides its clinical and surgical importance. The aims of the present study were to describe the brachial plexus anatomical variations in origin and respective branches, and to correlate these variations with sex, color of the subjects ...
Mass Losing Asymptotic Giant Branch Stars and Supergiants
Whitelock, Patricia A; Höfner, Susanne; Wittkowski, Markus; Zijlstra, Albert A
2016-01-01
This paper presents a summary of four invited and twelve contributed presentations on asymptotic giant branch stars and red supergiants, given over the course of two afternoon splinter sessions at the 19th Cool Stars Workshop. It highlights both recent observations and recent theory, with some emphasis on high spatial resolution, over a wide range of wavelengths. Topics covered include 3D models, convection, binary interactions, mass loss, dust formation and magnetic fields.
Bounds for Regularity and Coregularity of Graded Modules
Indian Academy of Sciences (India)
Reza Sazeedeh
2007-11-01
Let be a finitely generated graded module over a Noetherian homogeneous ring with local base ring $(R_0,\\mathfrak{m}_0)$. If 0 is of dimension one, then we show that $\\mathrm{reg}^i+1(M)$ and $\\mathrm{coreg}^{i+1}(M)$ are bounded for all $i\\in\\mathbb{N}_0$. We improve these bounds, if in addition, 0 is either regular or analytically irreducible of unequal characteristic.
Lipschitz spaces and bounded mean oscillation of harmonic mappings
Chen, Sh; Vuorinen, M; Wang, X
2012-01-01
In this paper, we first study the bounded mean oscillation of planar harmonic mappings, then a relationship between Lipschitz-type spaces and equivalent modulus of real harmonic mappings is established. At last, we obtain sharp estimates on Lipschitz number of planar harmonic mappings in terms of bounded mean oscillation norm, which shows that the harmonic Bloch space is isomorphic to $BMO_{2}$ as a Banach space.
Superconducting film magnetic flux transformer with micro- and nanosized branches
Directory of Open Access Journals (Sweden)
Levan Ichkitidze
2013-06-01
Full Text Available The object of the study is a superconducting film magnetic flux transformer comprising two square shaped loops with the tapering active strips and a magnetosensitive film element between them. It is shown that splitting of the active strips into parallel micro- and nanosized superconducting branches and slits increases the gain factor of the transformer, i. e., the concentration of an external magnetic field on the magnetosensitive element, by a factor of more than four.
Signaling mechanisms in cortical axon growth, guidance and branching
Directory of Open Access Journals (Sweden)
Katherine eKalil
2011-09-01
Full Text Available Precise wiring of cortical circuits during development depends upon axon extension, guidance and branching to appropriate targets. Motile growth cones at axon tips navigate through the nervous system by responding to molecular cues, which modulate signaling pathways within axonal growth cones. Intracellular calcium signaling has emerged as a major transducer of guidance cues but exactly how calcium signaling pathways modify the actin and microtubule cytoskeleton to evoke growth cone behaviors and axon branching is still mysterious. Axons must often pause in their outgrowth while their branches extend into targets. Some evidence suggests a competition between growth of axons and branches but the mechanisms are poorly understood. Since it is difficult to study growing axons deep within the mammalian brain, much of what we know about signaling pathways and cytoskeletal dynamics has come from studies of axonal growth cones, in many cases from non-mammalian species, growing in tissue culture. Consequently it is not well understood how guidance cues relevant to mammalian neural development in vivo signal to the growth cone cytoskeleton during axon outgrowth and guidance. In this review we describe our recent work in dissociated cultures of developing rodent sensorimotor cortex in the context of the current literature on molecular guidance cues, calcium signaling pathways and cytoskeletal dynamics that regulate growth cone behaviors. A major challenge is to relate findings in tissue culture to mechanisms of cortical development in vivo. Toward this goal, we describe our recent work in cortical slices, which preserve the complex cellular and molecular environment of the mammalian brain but allow direct visualization of growth cone behaviors and calcium signaling. Findings from this work suggest that mechanisms regulating axon growth and guidance in dissociated culture neurons also underlie development of cortical connectivity in vivo.
Institute of Scientific and Technical Information of China (English)
郑延斌; 郭凌云; 王宁
2012-01-01
Objective: to explore the correlation between metacognition ability and athletic ability of track man. Methods: by using questionnaire survey method , all date of metacognition ability grade is obtained. SPSS I 3. 0 for windows is employed in this paper to statistical analysis. Results:(1) for masters of sports and the second grade sportsmen, the first grade sportsmen and the second grade sportsmen,masters of sports and the second grade sportsmen,the significant differences do exist(P<< 0. 05);even there are remarkable significant differences between masters of sports and the second grade sportsmen(P<0. 01) , (2)metacognition ability are positively correlated to athletic ability of track man. Conclusions:metacognition ability does improve athletic ability of track man.%针对如何提高碰撞检测的实时性,提出了一种碰撞检测算法.该算法首先利用空间分解确定相邻物体,然后对相邻物体利用层次包围盒方法进行碰撞检测,在包围盒碰撞检测方面,提出了一种新的包围盒混合结构,这种混合结构结合了AABB包围盒相交测试的简单性和k-DOPs包围盒的紧密性.实验结果表明,该算法有效地提高了碰撞检测的实时性.
Proton binding by linear, branched, and hyperbranched polyelectrolytes
Koper, G.J.M.; Borkovec, M.
2010-01-01
This article reviews our understanding of ionization processes of weak polyelectrolytes. The emphasis is put on a general introduction to site binding models, which are able to account for many experimental features of linear and branched polyelectrolytes, including dendrimers. These models are fully compatible with the classical description of acid-base equilibria. The review further discusses the nature of the site-site interaction and role of conformational equilibria. Experimental chargin...
SM Higgs decay branching ratios and total Higgs width
Daniel Denegri
2001-01-01
Upper: Higgs decay ratios as a function of Higgs mass. The largest branching ratio is not necessarily the most usefull one. The most usefull ones are gamma gamma bbar ZZ and WW as in those modes latter signal to background ratios can be achieved. Lower: Total Higgs decay width versus Higgs mass. At low masses the natural width is extremely small, thus observability depends on instrumental resolution primarily.
Vertex Sparsifiers and Abstract Rounding Algorithms
Charikar, Moses; Li, Shi; Moitra, Ankur
2010-01-01
The notion of vertex sparsification is introduced in \\cite{M}, where it was shown that for any graph $G = (V, E)$ and a subset of $k$ terminals $K \\subset V$, there is a polynomial time algorithm to construct a graph $H = (K, E_H)$ on just the terminal set so that simultaneously for all cuts $(A, K-A)$, the value of the minimum cut in $G$ separating $A$ from $K -A$ is approximately the same as the value of the corresponding cut in $H$. We give the first super-constant lower bounds for how well a cut-sparsifier $H$ can simultaneously approximate all minimum cuts in $G$. We prove a lower bound of $\\Omega(\\log^{1/4} k)$ -- this is polynomially-related to the known upper bound of $O(\\log k/\\log \\log k)$. This is an exponential improvement on the $\\Omega(\\log \\log k)$ bound given in \\cite{LM} which in fact was for a stronger vertex sparsification guarantee, and did not apply to cut sparsifiers. Despite this negative result, we show that for many natural problems, we do not need to incur a multiplicative penalty fo...
Branch-and-cut-and-price for the traveling salesman problem with time windows
DEFF Research Database (Denmark)
Røpke, Stefan; Madsen, Oli B.G.
distance traveled by the salesman. The TSPTW is formulated as a set-partitioning problem which is solved by using combined cut and column generation. The pricing sub problem in the column generation procedure is a shortest path problem with time window constraints and 2-cycle elimination. A standard column...... generation process converges slowly for the problem and therefore a stabilization procedure is implemented. Valid inequalities expressed in the original, arc-based variables are added to the LP relaxation to strengthen the lower bound. The proposed algorithm is compared to exact algorithms based on other......In the traveling salesman problem with time windows (TSPTW) one is given a depot and a set of nodes to be visited by a salesman. The salesman starts his trip at the depot and must visit all nodes while respecting time windows at the nodes. The objective of the problem is to minimize the total...
Goal programming with bounded variables and post analysis%有界变量目标规划及后分析
Institute of Scientific and Technical Information of China (English)
胡清淮; 魏一鸣
2003-01-01
This paper outlines the algorithm of linear goal programming with bounded variables and its post analysis. An application of this method for selection of a preferable solution within the multiple solutions is demonstrated.
DEFF Research Database (Denmark)
Hansen, Anders Dohn; Kolind, Esben; Clausen, Jens
2009-01-01
In this paper, we consider the Manpower Allocation Problem with Time Windows, Job-Teaming Constraints and a limited number of teams (m-MAPTWTC). Given a set of teams and a set of tasks, the problem is to assign to each team a sequential order of tasks to maximize the total number of assigned tasks....... Both teams and tasks may be restricted by time windows outside which operation is not possible. Some tasks require cooperation between teams, and all teams cooperating must initiate execution simultaneously. We present an IP-model for the problem, which is decomposed using Dantzig-Wolfe decomposition....... The problem is solved by column generation in a Branch-and-Price framework. Simultaneous execution of tasks is enforced by the branching scheme. To test the efficiency of the proposed algorithm, 12 realistic test instances are introduced. The algorithm is able to find the optimal solution in 11 of the test...
DEFF Research Database (Denmark)
Hansen, Anders Dohn; Kolind, Esben; Clausen, Jens
In this paper, we consider the Manpower Allocation Problem with Time Windows, Job-Teaming Constraints and a limited number of teams (m-MAPTWTC). Given a set of teams and a set of tasks, the problem is to assign to each team a sequential order of tasks to maximize the total number of assigned tasks....... Both teams and tasks may be restricted by time windows outside which operation is not possible. Some tasks require cooperation between teams, and all teams cooperating must initiate execution simultaneously. We present an IP-model for the problem, which is decomposed using Dantzig-Wolfe decomposition....... The problem is solved by column generation in a Branch-and-Price framework. Simultaneous execution of tasks is enforced by the branching scheme. To test the efficiency of the proposed algorithm, 12 realistic test instances are introduced. The algorithm is able to find the optimal solution in 11 of the test...
Genetic Algorithm for Optimization: Preprocessor and Algorithm
Sen, S. K.; Shaykhian, Gholam A.
2006-01-01
Genetic algorithm (GA) inspired by Darwin's theory of evolution and employed to solve optimization problems - unconstrained or constrained - uses an evolutionary process. A GA has several parameters such the population size, search space, crossover and mutation probabilities, and fitness criterion. These parameters are not universally known/determined a priori for all problems. Depending on the problem at hand, these parameters need to be decided such that the resulting GA performs the best. We present here a preprocessor that achieves just that, i.e., it determines, for a specified problem, the foregoing parameters so that the consequent GA is a best for the problem. We stress also the need for such a preprocessor both for quality (error) and for cost (complexity) to produce the solution. The preprocessor includes, as its first step, making use of all the information such as that of nature/character of the function/system, search space, physical/laboratory experimentation (if already done/available), and the physical environment. It also includes the information that can be generated through any means - deterministic/nondeterministic/graphics. Instead of attempting a solution of the problem straightway through a GA without having/using the information/knowledge of the character of the system, we would do consciously a much better job of producing a solution by using the information generated/created in the very first step of the preprocessor. We, therefore, unstintingly advocate the use of a preprocessor to solve a real-world optimization problem including NP-complete ones before using the statistically most appropriate GA. We also include such a GA for unconstrained function optimization problems.
Capacity Bounds for Parallel Optical Wireless Channels
Chaaban, Anas
2016-01-01
A system consisting of parallel optical wireless channels with a total average intensity constraint is studied. Capacity upper and lower bounds for this system are derived. Under perfect channel-state information at the transmitter (CSIT), the bounds have to be optimized with respect to the power allocation over the parallel channels. The optimization of the lower bound is non-convex, however, the KKT conditions can be used to find a list of possible solutions one of which is optimal. The optimal solution can then be found by an exhaustive search algorithm, which is computationally expensive. To overcome this, we propose low-complexity power allocation algorithms which are nearly optimal. The optimized capacity lower bound nearly coincides with the capacity at high SNR. Without CSIT, our capacity bounds lead to upper and lower bounds on the outage probability. The outage probability bounds meet at high SNR. The system with average and peak intensity constraints is also discussed.
P2-16: Dual-Bound Model and the Role of Time Bound in Perceptual Decision Making
Directory of Open Access Journals (Sweden)
Daeseob Lim
2012-10-01
Full Text Available The diffusion model (DM encapsulates the dynamics of perceptual decision within a ‘diffusion field’ that is defined by a basis with sensory-evidence (SE and time vectors. At the core of the DM, it assumes that a decision is not made until an evidence particle drifts in the diffusion field and eventually hits one of the two pre-fixed bounds defined in the SE axis. This assumption dictates when and which choice is made by referring to when and which bound will be hit by the evidence particle. What if urgency pressures the decision system to make a choice even when the evidence particle has yet hit the SE bound? Previous modeling attempts at coping with time pressure, despite differences in detail, all manipulated the coordinate of SE bounds. Here, we offer a novel solution by adopting another bound on the time axis. This ‘dual-bound’ model (DBM posits that decisions can also be made when the evidence particle hits a time bound, which is determined on a trial-by-trial basis by a ‘perceived time interval’ – how long the system can stay in the ‘diffusion’ field. The classic single-bound model (SBM exhibited systematic errors in predicting both the reaction time distributions and the time-varying bias in choice. Those errors were not corrected by previously proposed variants of the SBM until the time bound was introduced. The validity of the DBM was further supported by the strong across-individual correlation between observed precision of interval timing and the predicted trial-by-trial variability of the time bound.
DEFF Research Database (Denmark)
Rasmussen, Marie-Louise Højlund; Stolpe, Mathias
2008-01-01
physics, and the cuts (Combinatorial Benders’ and projected Chvátal–Gomory) come from an understanding of the particular mathematical structure of the reformulation. The impact of a stronger representation is investigated on several truss topology optimization problems in two and three dimensions.......The subject of this article is solving discrete truss topology optimization problems with local stress and displacement constraints to global optimum. We consider a formulation based on the Simultaneous ANalysis and Design (SAND) approach. This intrinsically non-convex problem is reformulated to a...... mixed-integer linear program, which is solved with a parallel implementation of branch-and-bound. Additional valid inequalities and cuts are introduced to give a stronger representation of the problem, which improves convergence and speed up of the parallel method. The valid inequalities represent the...
Quantum Algorithms for Finding Claws, Collisions and Triangles
Buhrman, H; Hoyer, P; Magniez, F; Santha, M; De Wolf, R; Buhrman, Harry; Durr, Christoph; Hoyer, Peter; Magniez, Frederic; Santha, Miklos; Wolf, Ronald de
2000-01-01
We present several applications of quantum amplitude amplification to finding claws and collisions in ordered or unordered functions. Our algorithms generalize those of Brassard, Hoyer, and Tapp, and imply an N^{3/4} log(N) quantum upper bound for the element distinctness problem (contrasting with N\\log(N) classical complexity). We also give an algorithm to finding a triangle in a graph more efficiently than classically.
Punetha, Nirmal; Ramaswamy, Ramakrishna; Atay, Fatihcan M
2015-04-01
We study synchronization in bipartite networks of phase oscillators with general nonlinear coupling and distributed time delays. Phase-locked solutions are shown to arise, where the oscillators in each partition are perfectly synchronized among themselves but can have a phase difference with the other partition, with the phase difference necessarily being either zero or π radians. Analytical conditions for the stability of both types of solutions are obtained and solution branches are explicitly calculated, revealing that the network can have several coexisting stable solutions. With increasing value of the mean delay, the system exhibits hysteresis, phase flips, final state sensitivity, and an extreme form of multistability where the numbers of stable in-phase and antiphase synchronous solutions with distinct frequencies grow without bound. The theory is applied to networks of Landau-Stuart and Rössler oscillators and shown to accurately predict both in-phase and antiphase synchronous behavior in appropriate parameter ranges.
Plexin A3 and turnout regulate motor axonal branch morphogenesis in zebrafish.
Directory of Open Access Journals (Sweden)
Rajiv Sainath
Full Text Available During embryogenesis motor axons navigate to their target muscles, where individual motor axons develop complex branch morphologies. The mechanisms that control axonal branching morphogenesis have been studied intensively, yet it still remains unclear when branches begin to form or how branch locations are determined. Live cell imaging of individual zebrafish motor axons reveals that the first axonal branches are generated at the ventral extent of the myotome via bifurcation of the growth cone. Subsequent branches are generated by collateral branching restricted to their synaptic target field along the distal portion of the axon. This precisely timed and spatially restricted branching process is disrupted in turnout mutants we identified in a forward genetic screen. Molecular genetic mapping positioned the turnout mutation within a 300 kb region encompassing eight annotated genes, however sequence analysis of all eight open reading frames failed to unambiguously identify the turnout mutation. Chimeric analysis and single cell labeling reveal that turnout function is required cell non-autonomously for intraspinal motor axon guidance and peripheral branch formation. turnout mutant motor axons form the first branch on time via growth cone bifurcation, but unlike wild-type they form collateral branches precociously, when the growth cone is still navigating towards the ventral myotome. These precocious collateral branches emerge along the proximal region of the axon shaft typically devoid of branches, and they develop into stable, permanent branches. Furthermore, we find that null mutants of the guidance receptor plexin A3 display identical motor axon branching defects, and time lapse analysis reveals that precocious branch formation in turnout and plexin A3 mutants is due to increased stability of otherwise short-lived axonal protrusions. Thus, plexin A3 dependent intrinsic and turnout dependent extrinsic mechanisms suppress collateral branch
The Laplace Functional and Moments for Markov Branching Chains in Random Environments
Institute of Scientific and Technical Information of China (English)
HU Di-he; ZHANG Shu-lin
2005-01-01
The concepts of random Markov matrix, Markov branching chain in random environment (MBCRE) and Laplace functional of Markov branching chain in random environment (LFMBCRE) are introduced. The properties of LFMBCRE and the explicit formulas of moments of MBCRE are given.
DEFF Research Database (Denmark)
Shaik, Shahnoor S.; Obata, Toshihiro; Hebelstrup, Kim H;
2016-01-01
-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper......Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro......-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed...
Hybridizing multi-inver-over evolutionary algorithms with tabu search for the symmetric TSP
Bermúdez, Carlos; Minetti, Gabriela F.; Alfonso, Hugo; Gallard, Raúl Hector
2001-01-01
The travelling salesman problem (TSP) is a NP-hard problem. Techniques as either Branch and Bound or Dynamic Programming supplied the global optimum solution for instances with more than 7000 cities. But, ther needed more than 4 years of CPU time. Fortunately, faster algorithms (simulated annealing, tabu search, neural networks, and evolutionary computation) exist although they do not guarantee to find the global optimum. Recently an EA based on a operator inver-over [4], provides optimal ...
Floquet bound states around defects and adatoms in graphene
Lovey, D. A.; Usaj, Gonzalo; Foa Torres, L. E. F.; Balseiro, C. A.
2016-06-01
Recent studies have focused on laser-induced gaps in graphene which have been shown to have a topological origin, thereby hosting robust states at the sample edges. While the focus has remained mainly on these topological chiral edge states, the Floquet bound states around defects lack a detailed study. In this paper we present such a study covering large defects of different shape and also vacancy-like defects and adatoms at the dynamical gap at ℏ Ω /2 (ℏ Ω being the photon energy). Our results, based on analytical calculations as well as numerics for full tight-binding models, show that the bound states are chiral and appear in a number which grows with the defect size. Furthermore, while the bound states exist regardless of the type of the defect's edge termination (zigzag, armchair, mixed), the spectrum is strongly dependent on it. In the case of top adatoms, the bound state quasienergies depend on the adatoms energy. The appearance of such bound states might open the door to the presence of topological effects on the bulk transport properties of dirty graphene.
Algorithms for Protein Structure Prediction
DEFF Research Database (Denmark)
Paluszewski, Martin
-trace. Here we present three different approaches for reconstruction of C-traces from predictable measures. In our first approach [63, 62], the C-trace is positioned on a lattice and a tabu-search algorithm is applied to find minimum energy structures. The energy function is based on half-sphere-exposure (HSE......) and contact number (CN) measures only. We show that the HSE measure is much more information-rich than CN, nevertheless, HSE does not appear to provide enough information to reconstruct the C-traces of real-sized proteins. Our experiments also show that using tabu search (with our novel tabu definition......) is more robust than standard Monte Carlo search. In the second approach for reconstruction of C-traces, an exact branch and bound algorithm has been developed [67, 65]. The model is discrete and makes use of secondary structure predictions, HSE, CN and radius of gyration. We show how to compute good lower...
Pearson, David W; Batuski, David J
2014-01-01
Recent simulations of the densest portion of the Corona Borealis supercluster (A2061, A2065, A2067, and A2089) have shown virtually no possibility of extended gravitationally bound structure without inter-cluster matter (Pearson & Batuski). In contrast, recent analyses of the dynamics found that the clusters had significant peculiar velocities towards the supercluster centroid (Batiste & Batuski). In this paper we present the results of a thorough investigation of the CSC: we determine redshifts and virial masses for all 8 clusters associated with the CSC; repeat the analysis of Batiste & Batuski with the inclusion of A2056 and CL1529+29; estimate the mass of the supercluster by applying the virial theorem on the supercluster scale (e.g. Small et al.), the caustics method (e.g. Reisenegger et al.), and a new procedure using the spherical collapse model (SCM) with the results of the dynamical analysis (SCM+FP); and perform a series of simulations to assess the likelihood of the CSC being a gravitat...
Bijalwan, Vandana; Ali, Usman; Kesarwani, Atul Kumar; Yadav, Kamalendra; Mazumder, Koushik
2016-07-01
Hydroxycinnamic acid bound arabinoxylans (HCA-AXs) were extracted from brans of five Indian millet varieties and response surface methodology was used to optimize the extraction conditions. The optimal condition to obtain highest yield of millet HCA-AXs was determined as follows: time 61min, temperature 66°C, ratio of solvent to sample 12ml/g. Linkage analysis indicated that hydroxycinnamic acid bound arabinoxylan from kodo millet (KM-HCA-AX) contained comparatively low branched arabinoxylan consisting of 14.6% mono-substituted, 1.2% di-substituted and 41.2% un-substituted Xylp residues. The HPLC analysis of millet HCA-AXs showed significant variation in the content of three major bound hydroxycinnamic acids (caffeic, p-coumaric and ferulic acid). The antioxidant activity of millet HCA-AXs were evaluated using three in vitro assay methods (DPPH, FRAP and β-carotene linoleate emulsion assays) which suggested both phenolic acid composition and structural characteristics of arabinoxylans could be correlated to their antioxidant potential, the detailed structural analysis revealed that low substituted KM-HCA-AX exhibited relatively higher antioxidant activity compared to other medium and highly substituted HCA-AXs from finger (FM), proso (PM), barnyard (BM) and foxtail (FOXM) millet. PMID:27050114
International Nuclear Information System (INIS)
Geometry navigation plays the most fundamental role in Monte Carlo particle transport simulation. It's mainly responsible for locating a particle inside which geometry volume it is and computing the distance to the volume boundary along the certain particle trajectory during each particle history. Geometry navigation directly affects the run-time performance of the Monte Carlo particle transport simulation, especially for large scale complicated systems. Two geometry acceleration algorithms, the automatic neighbor search algorithm and the oriented bounding box algorithm, are presented for improving geometry navigation performance. The algorithms have been implemented in the Super Monte Carlo Calculation Program for Nuclear and Radiation Process (SuperMC) version 2.0. The FDS-II and ITER benchmark models have been tested to highlight the efficiency gains that can be achieved by using the acceleration algorithms. The exact gains may be problem dependent, but testing results showed that runtime of Monte Carlo simulation can be considerably reduced 50%∼60% with the proposed acceleration algorithms. (author)
DEFF Research Database (Denmark)
Achtziger, Wolfgang; Stolpe, Mathias
2009-01-01
we use the theory developed in Part I to design a convergent nonlinear branch-and-bound method tailored to solve large-scale instances of the original discrete problem. The problem formulation and the needed theoretical results from Part I are repeated such that this paper is self-contained. We focus...... on the implementation details but also establish finite convergence of the branch-and-bound method. The algorithm is based on solving a sequence of continuous non-convex relaxations which can be formulated as quadratic programs according to the theory in Part I. The quadratic programs to be treated...... within the branch-and-bound search all have the same feasible set and differ from each other only in the objective function. This is one reason for making the resulting branch-and-bound method very efficient. The paper closes with several large-scale numerical examples. These examples are, to the...
Information-Theoretic Bounded Rationality and ε-Optimality
Directory of Open Access Journals (Sweden)
Daniel A. Braun
2014-08-01
Full Text Available Bounded rationality concerns the study of decision makers with limited information processing resources. Previously, the free energy difference functional has been suggested to model bounded rational decision making, as it provides a natural trade-off between an energy or utility function that is to be optimized and information processing costs that are measured by entropic search costs. The main question of this article is how the information-theoretic free energy model relates to simple ε-optimality models of bounded rational decision making, where the decision maker is satisfied with any action in an ε-neighborhood of the optimal utility. We find that the stochastic policies that optimize the free energy trade-off comply with the notion of ε-optimality. Moreover, this optimality criterion even holds when the environment is adversarial. We conclude that the study of bounded rationality based on ε-optimality criteria that abstract away from the particulars of the information processing constraints is compatible with the information-theoretic free energy model of bounded rationality.
Soft bounds on diffusion produce skewed distributions and Gompertz growth
Mandrà, Salvatore; Lagomarsino, Marco Cosentino; Gherardi, Marco
2014-09-01
Constraints can affect dramatically the behavior of diffusion processes. Recently, we analyzed a natural and a technological system and reported that they perform diffusion-like discrete steps displaying a peculiar constraint, whereby the increments of the diffusing variable are subject to configuration-dependent bounds. This work explores theoretically some of the revealing landmarks of such phenomenology, termed "soft bound." At long times, the system reaches a steady state irreversibly (i.e., violating detailed balance), characterized by a skewed "shoulder" in the density distribution, and by a net local probability flux, which has entropic origin. The largest point in the support of the distribution follows a saturating dynamics, expressed by the Gompertz law, in line with empirical observations. Finally, we propose a generic allometric scaling for the origin of soft bounds. These findings shed light on the impact on a system of such "scaling" constraint and on its possible generating mechanisms.
A note on bound entanglement and local realism
Kaszlikowski, D; Gnacinski, P; Kaszlikowski, Dagomir; Zukowski, Marek; Gnacinski, Piotr
2001-01-01
We show using a numerical approach that gives necessary and sufficient conditions for the existence of local realism, that the bound entangled state presented in Bennett et. al. Phys. Rev. Lett. 82, 5385 (1999) admits a local and realistic description. We also find the lowest possible amount of some appropriate entangled state that must be ad-mixed to the bound entangled state so that the resulting density operator has no local and realistic description and as such can be useful in quantum communication and quantum computation.
Lower Bounds on Implementing Robust and Resilient Mediators
Abraham, Ittai; Halpern, Joseph Y
2007-01-01
We consider games that have (k,t)-robust equilibria when played with a mediator, where an equilibrium is (k,t)-robust if it tolerates deviations by coalitions of size up to k and deviations by up to $t$ players with unknown utilities. We prove lower bounds that match upper bounds on the ability to implement such mediators using cheap talk (that is, just allowing communication among the players). The bounds depend on (a) the relationship between k, t, and n, the total number of players in the system; (b) whether players know the exact utilities of other players; (c) whether there are broadcast channels or just point-to-point channels; (d) whether cryptography is available; and (e) whether the game has a $k+t)-punishment strategy; that is, a strategy that, if used by all but at most $k+t$ players, guarantees that every player gets a worse outcome than they do with the equilibrium strategy.
Bounded Delay Packet Scheduling in a Bounded Buffer
Fung, Stanley P Y
2009-01-01
We study the problem of buffer management in QoS-enabled network switches in the bounded delay model where each packet is associated with a weight and a deadline. We consider the more realistic situation where the network switch has a finite buffer size. A 9.82-competitive algorithm is known for the case of multiple buffers (Azar and Levy, SWAT'06). Recently, for the case of a single buffer, a 3-competitive deterministic algorithm and a 2.618-competitive randomized algorithm was known (Li, INFOCOM'09). In this paper we give a simple deterministic 2-competitive algorithm for the case of a single buffer.
Institute of Scientific and Technical Information of China (English)
Yan Xia REN
2008-01-01
The global supports of super-Poisson processes and super-random walks with a branching mechanism ψ(z)=z2 and constant branching rate are known to be noncompact. It turns out that, for any spatially dependent branching rate, this property remains true. However, the asymptotic extinction property for these two kinds of superprocesses depends on the decay rate of the branching-rate function at infinity.
Tightened Exponential Bounds for Discrete-Time Conditionally Symmetric Martingales and Applications
Sason, Igal
2012-01-01
This paper revisits the derivation of some exponential bounds for discrete-time and real-valued martingales with bounded jumps in order to improve these bounds for conditionally symmetric martingales. The new bounds are extended to conditionally symmetric sub or super-martingales, and they are also considered in connection to some previously reported bounds in the literature. Two applications of these bounds are exemplified in the context of gambling, and the number of up-crossings of a super-martingale.
Stability and response bounds of non-conservative linear systems
DEFF Research Database (Denmark)
Kliem, Wolfhard; Pommer, Christian
2004-01-01
This paper develops a stability theorem and response bounds for non-conservative systems of the form MX + (D + G)x + (K + N)x = f(t), with hermitian positive-definite matrices M, D and K, and skew-hermitian matrices G and N. To this end, we first find a Lyapunov function by solving the Lyapunov...... matrix equation. Then, if a system satisfies the condition of the stability theorem, the associated Lyapunov function can be used to obtain response bounds for the norms as well as for the individual coordinates of the solution. Examples from rotor dynamics illustrate the results....
Flow Equations for N Point Functions and Bound States
Ellwanger, Ulrich
1994-01-01
We discuss the exact renormalization group or flow equation for the effective action and its decomposition into one particle irreducible N point functions. With the help of a truncated flow equation for the four point function we study the bound state problem for scalar fields. A combination of analytic and numerical methods is proposed, which is applied to the Wick-Cutkosky model and a QCD-motivated interaction. We present results for the bound state masses and the Bethe-Salpeter wave function. (Figs. 1-4 attached as separate uuencoded post-script files.)
Research on Power Line as Communication Channel with Multi-Tap and Multi-Branch Configuration
Directory of Open Access Journals (Sweden)
Yanhua Zheng
2013-12-01
Full Text Available To study the effect of different branch configuration on transmission characteristic in-home low-voltage (LV communication power line communication (PLC channel, the influences of branch length, number of branch and tap, and branch terminal impedance on the performance of PLC are investigated. The two type power line network structures of the one-tap with multi-branch (OTMB and the multi-tap with multi-branch (MTMB are studied. The transmission characteristics of the PLC channel are simulated by varying the length and terminal impedance of the branch for two configurations. Simulation results show that the length and terminal impedance of the branch have significant influence on the amplitude and phase response of the transfer function. The position and number of notches and crests in the amplitude responses are affected by different branch types and the configurations of branch length and branch terminal impedance. The models developed in this paper can easily handle an arbitrary topology of power line channel and provide accurate calculation for the channel responses of the all kinds of channel branch structures in indoor LV power line network
Weber, Y.; De Jonge, C.; Rijpstra, W.I.C.; Hopmans, E. C.; Stadnitskaia, A.; Schubert, C J; Lehmann, M.F.; Sinninghe Damsté, J. S.; Niemann, H.
2015-01-01
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are bacterial membrane lipids that occur ubiquitously in soils and lacustrine sediments and have great potential as proxy indicators for paleotemperature and pH reconstructions. Initially, brGDGTs in lakes were thought to originate from soils of the watershed. The composition of the lacustrine brGDGT pool, however, often differs substantially from that in catchment soils, complicating the application of the brGDGT paleothermometer to la...
Hilbert series and mixed branches of $T[SU(N)]$ theory
Carta, Federico
2016-01-01
We consider mixed branches of 3d $\\mathcal{N}=4$ $T[SU(N)]$ theory. We compute the Hilbert series of the Coulomb branch part of the mixed branch from a restriction rule acting on the Hilbert series of the full Coulomb branch that will truncate the magnetic charge summation only to the subset of BPS dressed monopole operators that arise in the Coulomb branch sublocus where the mixed branch stems. This restriction can be understood directly from the type IIB brane picture by a relation between the magnetic charges of the monopoles and brane position moduli. We also apply the restriction rule to the Higgs branch part of a given mixed branch by exploiting 3d mirror symmetry. Both cases show complete agreement with the results calculated by different methods.
Public Relations as Scientific Branch of Information and Communication Sciences
Directory of Open Access Journals (Sweden)
Hrvoje Jakopović
2012-06-01
Full Text Available Given that the field of information and communication sciences is a young field in the social sciences, it is important to consider how technology impacts the development of this field. This is especially relevant when looking at the area of public relations. Amid changing technological developments public relations is constantly being redefined in this complex environment. This work focuses on the development of public relations as a branch of study in the field of information and communication sciences. I review the scientific methods used to evaluate the influence and effects of public relations, while discussing the different methodological approaches.
Optimized Ultrawideband and Uniplanar Minkowski Fractal Branch Line Coupler
Directory of Open Access Journals (Sweden)
Mohammad Jahanbakht
2012-01-01
Full Text Available The non-Euclidean Minkowski fractal geometry is used in design, optimization, and fabrication of an ultrawideband (UWB branch line coupler. Self-similarities of the fractal geometries make them act like an infinite length in a finite area. This property creates a smaller design with broader bandwidth. The designed 3 dB microstrip coupler has a single layer and uniplanar platform with quite easy fabrication process. This optimized 180° coupler also shows a perfect isolation and insertion loss over the UWB frequency range of 3.1–10.6 GHz.
CBC bound proteins and RNA fate
DEFF Research Database (Denmark)
Giacometti, Simone
2016-01-01
) complex (CBCN), were recently shown to target capped RNA either toward export or degradation, but the mechanisms by which they can discriminate between different RNA families and route them toward different metabolic pathways still remain unclear. A major question to be answered is how and when...... the different CBC subcomplexes are recruited to the RNP. Here, we used an individual nucleotide-resolution UV cross-linking and immunoprecipitation (iCLIP) approach to identify the transcriptome-wide targets for 5 different components of the CBCAP and CBCN complexes, and compared results to the previously......), while MTR4 is additionally present on mature RNAs. Although more experimental work is needed to fully support our model, we propose that CBCAP and CBCN bind overlapping sets of RNAs, indicating a competition between the proteins ZC3H18 and PHAX, and the lack of a strict RNA sorting mechanism. RNA fate...
Bound and continuum vibrational states of the bifluoride anion
Špirko, V.; Šindelka, M.; Shirsat, R. N.; Leszczynski, J.
2003-07-01
The energies of the bound vibrational states and energy density spectra of the continuum vibrational states of FHF - are calculated, 'exactly' and 'adiabatically', using a new ab initio (CCSD(T)) potential energy surface. Statistical properties of the bound states are probed in terms of the density of states and nearest neighbor level spacing distributions (NNSD). Importantly, the approximate 'adiabatic' densities coincide nearly quantitatively with their 'exact' counterparts. A quantitative fitting of the NNSDs is achieved with a new empirical modification of the Wigner distribution.
Characterization of linear and branched polyacrylates by tandem mass spectrometry.
Chaicharoen, Kittisak; Polce, Michael J; Singh, Anirudha; Pugh, Coleen; Wesdemiotis, Chrys
2008-10-01
The unimolecular degradation of alkali-metal cationized polyacrylates with the repeat unit CH(2)CH(COOR) and a variety of ester pendants has been examined by tandem mass spectrometry. The fragmentation patterns resulting from collisionally activated dissociation depend sensitively on the size of the ester alkyl substituent (R). With small alkyl groups, as in poly(methyl acrylate), lithiated or sodiated oligomers (M) decompose via free-radical chemistry, initiated by random homolytic C-C bond cleavages along the polymer chain. The radical ions formed this way dissociate further by backbiting rearrangements and beta scissions to yield a distribution of terminal fragments with one of the original end groups and internal fragments with 2-3 repeat units. If the ester alkyl group bears three or more carbon atoms, cleavages within the ester moieties become the predominant decomposition channel. This distinct reactivity is observed if R = t-butyl, n-butyl, or the mesogenic group (CH(2))(11)-O-C(6)H(4)-C(6)H(4)-CN. The [M+alkali metal](+) ions of the latter polyacrylates dissociate largely by charge-remote 1,5-H rearrangements that convert COOR to COOH groups by expulsion of 1-alkenes. The acid groups may displace an alcohol unit from a neighboring ester pendant to form a cyclic anhydride, unless hindered by steric effects. Using atom transfer radical polymerization, hyperbranched polyacrylates were prepared carrying ester groups both within and between the branches. Unique alkenes and alcohols are cleaved from ester groups at the branching points, enabling determination of the branching architecture. PMID:18373231
Bogoliubov Excited States and the Lyth Bound
Aravind, Aditya; Paban, Sonia
2014-01-01
We show that Bogoliubov excited scalar and tensor modes do not alleviate Planckian evolution during inflation if one assumes that $r$ and the Bogoliubov coefficients are approximately scale invariant. We constrain the excitation parameter for the scalar fluctuations, $\\beta$, and tensor perturbations, $\\tilde{\\beta}$, by requiring that there be at least three decades of scale invariance in the scalar and tensor power spectrum. For the scalar fluctuations this is motivated by the observed nearly scale invariant scalar power spectrum. For the tensor fluctuations this assumption may be shown to be valid or invalid by future experiments.
31 CFR 359.71 - What is the role of Federal Reserve Banks and Branches?
2010-07-01
... UNITED STATES SAVINGS BONDS, SERIES I Miscellaneous Provisions § 359.71 What is the role of Federal Reserve Banks and Branches? (a) Federal Reserve Banks and Branches are fiscal agents of the United States... Federal Reserve Bank, Buffalo Branch, 160 Delaware Avenue, Buffalo, NY 14202 New York, Boston...
31 CFR 351.86 - What is the role of Federal Reserve Banks and Branches?
2010-07-01
... UNITED STATES SAVINGS BONDS, SERIES EE Miscellaneous Provisions § 351.86 What is the role of Federal Reserve Banks and Branches? (a) Federal Reserve Banks and Branches are fiscal agents of the United States... Federal Reserve Bank, Buffalo Branch, 160 Delaware Avenue, Buffalo, NY 14202 New York, Boston...
THE EXISTENCE AND MOMENTS OF CANONICAL BRANCHING CHAIN IN RANDOM ENVIRONMENT
Institute of Scientific and Technical Information of China (English)
胡迪鹤
2004-01-01
The concepts of branching chain in random environmnet and canonical branching chain in random environment axe introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical expectation and variance of branching chain in random environment axe also given.
Size-change Termination and Bound Analysis
DEFF Research Database (Denmark)
Avery, James Emil
2006-01-01
Despite its simplicity, the size-change termination principle, presented by Lee, Jones and Ben-Amram in [LJB01], is surprisingly strong and is able to show termination for a large class of programs. A significant limitation for its use, however, is the fact that the SCT requires data types...
Anxiety and the Outward Bound Process.
Drebing, Charles E.; And Others
1987-01-01
Hypothesized ways in which level of participants' anxiety affected their experience during outdoor adventure course. Studies anxiety levels of 27 male and 13 female incoming Wheaton College freshmen participating in 3-week High Road Program involving solar experiences, rock climbing, and rappelling. (NEC)
Tau reconstruction and identification algorithm
Indian Academy of Sciences (India)
Raman Khurana
2012-11-01
CMS has developed sophisticated tau identification algorithms for tau hadronic decay modes. Production of tau lepton decaying to hadrons are studied at 7 TeV centre-of-mass energy with 2011 collision data collected by CMS detector and has been used to measure the performance of tau identification algorithms by measuring identification efficiency and misidentification rates from electrons, muons and hadronic jets. These algorithms enable extended reach for the searches for MSSM Higgs, and other exotic particles.
Mirror World and Axion: Relaxing Cosmological Bounds
Maurizio, G
2005-01-01
The cosmological (upper) limit on the Peccei-Quinn constant, related to the primordial oscillations of the axion field, can be relaxed for a mirror axion model. The simple reason is that the mirror world is colder and so the behavior of the axion temperature-dependent mass is dominated by the contribution from the mirror sector. So the coherent oscillations start earlier and correspondingly the axion mass density \\Omega_a h^2 is reduced.
Quantum Gravity Mathematical Models and Experimental Bounds
Fauser, Bertfried; Zeidler, Eberhard
2007-01-01
The construction of a quantum theory of gravity is the most fundamental challenge confronting contemporary theoretical physics. The different physical ideas which evolved while developing a theory of quantum gravity require highly advanced mathematical methods. This book presents different mathematical approaches to formulate a theory of quantum gravity. It represents a carefully selected cross-section of lively discussions about the issue of quantum gravity which took place at the second workshop "Mathematical and Physical Aspects of Quantum Gravity" in Blaubeuren, Germany. This collection covers in a unique way aspects of various competing approaches. A unique feature of the book is the presentation of different approaches to quantum gravity making comparison feasible. This feature is supported by an extensive index. The book is mainly addressed to mathematicians and physicists who are interested in questions related to mathematical physics. It allows the reader to obtain a broad and up-to-date overview on ...
Black hole bound states and their quantization
J. de Boer
2007-01-01
We briefly review the construction of multi-centered black hole solutions in type IIA string theory. We then discuss a decoupling limit which embeds these solutions in M-theory on AdS(3) x S-2 x CY, and discuss some aspects of their dual CFT interpretation. Finally, we consider the quantization of t
Lyapunov Exponents for Branching Processes in a Random Environment: The Effect of Information
Hautphenne, Sophie; Latouche, Guy
2016-04-01
We consider multitype branching processes evolving in a Markovian random environment. To determine whether or not the branching process becomes extinct almost surely is akin to computing the maximal Lyapunov exponent of a sequence of random matrices, which is a notoriously difficult problem. We define Markov chains associated to the branching process, and we construct bounds for the Lyapunov exponent. The bounds are obtained by adding or by removing information: to add information results in a lower bound, to remove information results in an upper bound, and we show that adding less information improves the lower bound. We give a few illustrative examples and we observe that the upper bound is generally more accurate than the lower bounds.
Power generation assets. Energy constraints, upper bounds and hedging strategies
Energy Technology Data Exchange (ETDEWEB)
Enge, Thomas
2010-09-20
The overall topic of this thesis is the valuation of power generation assets under energy and risk constraints. Our focus is on the modeling aspect i.e. to find the right balance between accuracy and computational feasibility. We define a new not yet investigated unit commitment problem that introduces an energy constraint to a thermal power plant. We define a continuous stochastic dynamic program with a nested mixed integer program (MIP). We introduce a fast implementation approach by replacing the MIP with an efficient matrix calculation and use principal component analysis to reduce the number of risk factors. We also provide a fast heuristic valuation approach for comparison. As both models can only provide lower bounds of the asset value, we investigate the theory of upper bounds for a proper validation of our power plant results. We review the primal dual algorithm for swing options by Meinshausen and Hambly and in particular clarify their notation and implementation. Then we provide an extension for swing options with multiple exercises at the same stage that we developed together with Prof. Bender, University of Braunschweig. We outline Prof. Bender's proof and describe the implementation in detail. Finally we provide a risk analysis for our thermal power plant. In particular we investigate strategies to reduce spot price risk to which power plants are significantly exposed. First, we focus on the measurement of spot price risk and propose three appropriate risk figures (Forward delta as opposed to Futures delta, synthetic spot delta and Earnings-at-Risk) and illustrate their application using a business case. Second we suggest risk mitigation strategies for both periods, before and in delivery. The latter tries to alter the dispatch policy i.e. pick less risky hours and accept a (desirably only slightly) smaller return. We introduce a benchmark that weighs risk versus return and that we will call EaR-efficient option value. We propose a mitigation
Third annual Walker Branch watershed research symposium: Programs and abstracts
International Nuclear Information System (INIS)
The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. Regional and global issues addressed by presentations include emissions of carbon dioxide, methane, and other hydrocarbons; deposition of sulfate, nitrate, and mercury; land-use changes; biological diversity; droughts; and water quality. The Department of Energy's local research site, Walker Branch Watershed, is a long-term ecosystem research project initiated on the Oak Ridge Reservation in 1967. Walker Branch provides a well-characterized site where many of these methods can be tested and applied.In addition, other large-scale experiments represented in this symposium include experiments on the effects of clearcutting and burning on forest structure and productivity associated with Coweeta Hydrologic Laboratory, and whole-tree ozone exposure chambers constructed by TVA and ORNL researchers
Direct Heuristic Algorithm for Linear Programming
Directory of Open Access Journals (Sweden)
I. Ramesh Babu
2013-08-01
Full Text Available Many applications in business and economics involve a process called optimization, in which we will be required to find the minimum cost, the maximum profit, or the minimum use of resources, where a decision maker may want to utilize limited available resources in the best possible manner. The limited resources may include material, money, manpower, space and time. Linear Programming provides various methods of solving such problems. The formulation of linear programming problem as a mathematical model is one type of optimization problem called linear programming. There are various methods for solving the linear programming problems. Some of them are approximation algorithm , branch and bound methods, cutting plane method etc. Other than Gomory’s cutting plane method, Branch and bound method LPP along with the DHALP (Direct heuristic algorithm for linear programming algorithm which is more efficient than these existing methods will be used for solving linear programming problems. An optimality test will also be included in this. Numerical experiments will depict the utility/scope of such a procedure.
Lifetimes, branching ratios, and transition probabilities in Co ii
Salih, S.; Lawler, J. E.; Whaling, W.
1985-01-01
The radiative lifetime of 14 levels in the z^5F, z^5D, and z^5G terms of Co ii have been measured with use of time-resolved laser fluorescence spectroscopy with a Co+-ion beam. Our lifetime values are shorter by 15–50 % than earlier results from beam-foil time-of-flight measurements. The lifetimes were converted to 41 individual transition probabilities with use of branching ratios measured on spectra recorded with the 1-m Fourier-transform spectrometer at the Kitt Peak National Observatory. ...
Engineering the Divide-and-Conquer Closest Pair Algorithm
Institute of Scientific and Technical Information of China (English)
Ming-hui Jiang; Joel gillespie
2007-01-01
We improve the famous divide-and-conquer algorithm by Bentley and Shamos for the planar closest-pair problem. For n points on the plane, our algorithm keeps the optimal O(n log n) time complexity and, using a circle-packing property, computes at most 7n/2 Euclidean distances, which improves Ge et al.'s bound of (3n log n)/2 Euclidean distances. We present experimental results of our comparative studies on four different versions of the divide-and-conquer closest pair algorithm and propose two effective heuristics.
Biggins, J D
2010-01-01
Results on the behaviour of the rightmost particle in the $n$th generation in the branching random walk are reviewed and the phenomenon of anomalous spreading speeds, noticed recently in related deterministic models, is considered. The relationship between such results and certain coupled reaction-diffusion equations is indicated.
Vegetation survey of Pen Branch and Four Mile Creek wetlands
Energy Technology Data Exchange (ETDEWEB)
1992-01-01
One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.
Vegetation survey of Pen Branch and Four Mile Creek wetlands
Energy Technology Data Exchange (ETDEWEB)
1992-10-01
One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.
Variance bounding Markov chains
Roberts, Gareth O.; Jeffrey S. Rosenthal
2008-01-01
We introduce a new property of Markov chains, called variance bounding. We prove that, for reversible chains at least, variance bounding is weaker than, but closely related to, geometric ergodicity. Furthermore, variance bounding is equivalent to the existence of usual central limit theorems for all L2 functionals. Also, variance bounding (unlike geometric ergodicity) is preserved under the Peskun order. We close with some applications to Metropolis–Hastings algorithms.
Linear Programming, the Simplex Algorithm and Simple Polytopes
Directory of Open Access Journals (Sweden)
Das Bhusan
2010-09-01
Full Text Available In the first part of the paper we survey some far reaching applications of the basis facts of linear programming to the combinatorial theory of simple polytopes. In the second part we discuss some recent developments concurring the simplex algorithm. We describe sub-exponential randomized pivot roles and upper bounds on the diameter of graphs of polytopes.
Branched and fenestrated options to treat aortic arch aneurysms.
Maurel, Blandine; Mastracci, Tara M; Spear, Rafaelle; Hertault, Adrien; Azzaoui, Richard; Sobocinski, Jonathan; Haulon, Stephan
2016-10-01
Conventional surgical repair of aortic arch aneurysms using cardiopulmonary bypass and hypothermic circulatory arrest remains the gold standard, however it is associated with a substantial mortality and morbidity rate, especially in the elderly. Hybrid techniques avoid aortic cross-clamping and circulatory arrest, but are of limited use and are only applicable to selected patients. The development of new devices to treat aortic arch aneurysms endovascularly has the potential to offer a treatment modality to patients unfit for an open repair. We present the challenges specific to endovascular arch repair based on our experience and the literature available from the first experience in 1999 to the third generation graft currently commonly used. Following an initial learning curve associated with the use of the third generation arch branch device, along with careful patient selection and operator experience, early results are promising. Technical success was achieved in all cases, there was no early mortality and strokes were noted in 11%. As with branched and fenestrated technology for thoracoabdominal aneurysm repair, the use of total endovascular repair for arch pathology will require an evolution in endovascular practice and device design. However, at present, the early use of the latest generation device offers a novel approach to patients who previously had no surgical options. PMID:27332680
Bound States and Supercriticality in Graphene-Based Topological Insulators
Directory of Open Access Journals (Sweden)
Reinhold Egger
2013-01-01
Full Text Available We study the bound state spectrum and the conditions for entering a supercritical regime in graphene with strong intrinsic and Rashba spin-orbit interactions within the topological insulator phase. Explicit results are provided for a disk-shaped potential well and for the Coulomb center problem.
Formation of Anodic Aluminum Oxide with Branched and Meshed Pores.
Kim, Byeol; Lee, Jin Seok
2016-06-01
Anodic aluminum oxide (AAO), with a self-ordered hexagonal array, is important for various applications in nanofabrication including as the fabrication of nanotemplates and other nanostructures. With the consideration, there have been many efforts to control the characteristic parameters of porous anodic alumina by adjustment of the anodizing conditions such as the electrolyte, temperature, applied potential, and Al purity. In particular, impurities in Al are changing the morphology of an alumina film; however, the formation mechanism has not yet been explained. In this work, we anodized a high purity (99.999%, Al(high)) and low purity (99.8%, Al(low)) aluminum foil by a two-step anodization process in an oxalic acid solution or phosphoric acid. It was found that the purity of aluminum foil has influenced the morphology of the alumina film resulting in branched and meshed pores. Also, electrochemical analysis indicated that the branched and meshed pores in the low-purity Al foil formed by the presence of impurities. Impurities act as defects and change the general growth mechanism for pore formation by inducing an electric field imbalance during anodization. This work contributes to the research field of topographical chemistry and applied fields including nanofabrication. PMID:27427755
The interplay of intrinsic and extrinsic bounded noises in biomolecular networks.
Directory of Open Access Journals (Sweden)
Giulio Caravagna
Full Text Available After being considered as a nuisance to be filtered out, it became recently clear that biochemical noise plays a complex role, often fully functional, for a biomolecular network. The influence of intrinsic and extrinsic noises on biomolecular networks has intensively been investigated in last ten years, though contributions on the co-presence of both are sparse. Extrinsic noise is usually modeled as an unbounded white or colored gaussian stochastic process, even though realistic stochastic perturbations are clearly bounded. In this paper we consider Gillespie-like stochastic models of nonlinear networks, i.e. the intrinsic noise, where the model jump rates are affected by colored bounded extrinsic noises synthesized by a suitable biochemical state-dependent Langevin system. These systems are described by a master equation, and a simulation algorithm to analyze them is derived. This new modeling paradigm should enlarge the class of systems amenable at modeling. We investigated the influence of both amplitude and autocorrelation time of a extrinsic Sine-Wiener noise on: (i the Michaelis-Menten approximation of noisy enzymatic reactions, which we show to be applicable also in co-presence of both intrinsic and extrinsic noise, (ii a model of enzymatic futile cycle and (iii a genetic toggle switch. In (ii and (iii we show that the presence of a bounded extrinsic noise induces qualitative modifications in the probability densities of the involved chemicals, where new modes emerge, thus suggesting the possible functional role of bounded noises.
QCA & CQCA: Quad Countries Algorithm and Chaotic Quad Countries Algorithm
Directory of Open Access Journals (Sweden)
M. A. Soltani-Sarvestani
2012-09-01
Full Text Available This paper introduces an improved evolutionary algorithm based on the Imperialist Com-petitive Algorithm (ICA, called Quad Countries Algorithm (QCA and with a little change called Chaotic Quad Countries Algorithm (CQCA. The Imperialist Competitive Algorithm is inspired by socio-political process of imperialistic competition in the real world and has shown its reliable performance in optimization problems. This algorithm converges quickly, but is easily stuck into a local optimum while solving high-dimensional optimization prob-lems. In the ICA, the countries are classified into two groups: Imperialists and Colonies which Imperialists absorb Colonies, while in the proposed algorithm two other kinds of countries, namely Independent and Seeking Independence countries, are added to the coun-tries collection which helps to more exploration. In the suggested algorithm, Seeking Inde-pendence countries move in a contrary direction to the Imperialists and Independent countries move arbitrarily that in this paper two different movements are considered for this group; random movement (QCA and Chaotic movement (CQCA. On the other hand, in the ICA the Imperialists’ positions are fixed, while in the proposed algorithm, Imperialists will move if they can reach a better position compared to the previous position. The proposed algorithm was tested by famous benchmarks and the compared results of the QCA and CQCA with results of ICA, Genetic Algorithm (GA, Particle Swarm Optimization (PSO, Particle Swarm inspired Evolutionary Algorithm (PS-EA and Artificial Bee Colony (ABC show that the QCA has better performance than all mentioned algorithms. Between all cases, the QCA, ABC and PSO have better performance respectively about 50%, 41.66% and 8.33% of cases.
Horizontal Branch evolution, metallicity and sdB stars
Michaud, G; Richard, O
2011-01-01
Context. Abundance anomalies have been observed in field sdB stars and in nearly all Horizontal Branch (HB) stars of globular clusters with Teff > 11 000K whatever be the cluster metallicity. Aims. The aim is to determine the abundance variations to be expected in sdB stars and in HB stars of metallicities Z \\geq 0.0001 and what observed abundances teach us about hydrodynamical processes competing with atomic diffusion. Methods. Complete stellar evolution models, including the effects of atomic diffusion and radiative acceleration, have been computed from the zero age main-sequence for metallicities of Z0 = 0.0001, 0.001, 0.004 and 0.02. On the HB the masses were selected to cover the Teff interval from 7000 to 37000K. Some 60 evolutionary HB models were calculated. The calculations of surface abundance anomalies during the horizontal branch depend on one parameter, the surface mixed mass. Results. For sdB stars with Teff 11 000K in all observed clusters, independent of metallicity, it was found that most ob...
Advanced Branching Control and Characterization of Inorganic Semiconducting Nanocrystals
Energy Technology Data Exchange (ETDEWEB)
Hughes, Steven Michael [Univ. of California, Berkeley, CA (United States)
2007-01-01
The ability to finely tune the size and shape of inorganic semiconducting nanocrystals is an area of great interest, as the more control one has, the more applications will be possible for their use. The first two basic shapes develped in nanocrystals were the sphere and the anistropic nanorod. the II_VI materials being used such as Cadmium Selenide (CdSe) and Cadmium Telluride (CdTe), exhibit polytypism, which allows them to form in either the hexagonally packed wurtzite or cubically packed zinc blende crystalline phase. The nanorods are wurtzite with the length of the rod growing along the c-axis. As this grows, stacking faults may form, which are layers of zinc blende in the otherwise wurtzite crystal. Using this polytypism, though, the first generation of branched crystals were developed in the form of the CdTe tetrapod. This is a nanocrystal that nucleates in the zincblend form, creating a tetrahedral core, on which four wurtzite arms are grown. This structure opened up the possibility of even more complex shapes and applications. This disseration investigates the advancement of branching control and further understanding the materials polytypism in the form of the stacking faults in nanorods.
Towards flavored bound states beyond rainbows and ladders
El-Bennich, B; Paracha, M A; de Melo, J P B C
2013-01-01
We give a snapshot of recent progress in solving the Dyson-Schwinger equation with a beyond rainbow-ladder ansatz for the dressed quark-gluon vertex which includes ghost contributions. We discuss the motivations for this approach with regard to heavy-flavored bound states and form factors and briefly describe future steps to be taken.
Towards flavored bound states beyond rainbows and ladders
Energy Technology Data Exchange (ETDEWEB)
El-Bennich, B.; Rojas, E.; Melo, J. P. B. C. de [Laboratório de Física Teórica e Computacional, Universidade Cruzeiro do Sul, São Paulo 01506-000 SP (Brazil); Paracha, M. A. [Laboratorio de Fisica Teorica e Computacional, Universidade Cruzeiro do Sul, Sao Paulo 01506-000 SP, Brazil and Centre for Advanced Mathematics and Physics, National University of Science and Technology, Islamabad (Pakistan)
2014-11-11
We give a snapshot of recent progress in solving the Dyson-Schwinger equation with a beyond rainbow-ladder ansatz for the dressed quark-gluon vertex which includes ghost contributions. We discuss the motivations for this approach with regard to heavy-flavored bound states and form factors and briefly describe future steps to be taken.
Institute of Scientific and Technical Information of China (English)
ZHANG Lina; DING Qiong
1995-01-01
A method of determining branching parameter of lacquer polysaccharide was established by acid-base back-titration of terminal uronic acid of branches. The branching factors obtained are in agreement with the values determined by colorimetric method with carbazole and the results estimated by using Zimm-Stockmayer equation from viscosity data. Influences of molecular weights and branching factors of five fractions of lacquer polysaccharide on the bioactivities were studied. The results show that the polysaccharides have bioactivities in motivating the growth of leucocytes, and the effect increases with the decrease of molecular weight and branching factor in the range studied(17×104＞Mw＞4×104).
Strepsiptera, phylogenomics and the long branch attraction problem.
Directory of Open Access Journals (Sweden)
Bastien Boussau
Full Text Available Insect phylogeny has recently been the focus of renewed interest as advances in sequencing techniques make it possible to rapidly generate large amounts of genomic or transcriptomic data for a species of interest. However, large numbers of markers are not sufficient to guarantee accurate phylogenetic reconstruction, and the choice of the model of sequence evolution as well as adequate taxonomic sampling are as important for phylogenomic studies as they are for single-gene phylogenies. Recently, the sequence of the genome of a strepsipteran has been published and used to place Strepsiptera as sister group to Coleoptera. However, this conclusion relied on a data set that did not include representatives of Neuropterida or of coleopteran lineages formerly proposed to be related to Strepsiptera. Furthermore, it did not use models that are robust against the long branch attraction artifact. Here we have sequenced the transcriptomes of seven key species to complete a data set comprising 36 species to study the higher level phylogeny of insects, with a particular focus on Neuropteroidea (Coleoptera, Strepsiptera, Neuropterida, especially on coleopteran taxa considered as potential close relatives of Strepsiptera. Using models robust against the long branch attraction artifact we find a highly resolved phylogeny that confirms the position of Strepsiptera as a sister group to Coleoptera, rather than as an internal clade of Coleoptera, and sheds new light onto the phylogeny of Neuropteroidea.
Strepsiptera, phylogenomics and the long branch attraction problem.
Boussau, Bastien; Walton, Zaak; Delgado, Juan A; Collantes, Francisco; Beani, Laura; Stewart, Isaac J; Cameron, Sydney A; Whitfield, James B; Johnston, J Spencer; Holland, Peter W H; Bachtrog, Doris; Kathirithamby, Jeyaraney; Huelsenbeck, John P
2014-01-01
Insect phylogeny has recently been the focus of renewed interest as advances in sequencing techniques make it possible to rapidly generate large amounts of genomic or transcriptomic data for a species of interest. However, large numbers of markers are not sufficient to guarantee accurate phylogenetic reconstruction, and the choice of the model of sequence evolution as well as adequate taxonomic sampling are as important for phylogenomic studies as they are for single-gene phylogenies. Recently, the sequence of the genome of a strepsipteran has been published and used to place Strepsiptera as sister group to Coleoptera. However, this conclusion relied on a data set that did not include representatives of Neuropterida or of coleopteran lineages formerly proposed to be related to Strepsiptera. Furthermore, it did not use models that are robust against the long branch attraction artifact. Here we have sequenced the transcriptomes of seven key species to complete a data set comprising 36 species to study the higher level phylogeny of insects, with a particular focus on Neuropteroidea (Coleoptera, Strepsiptera, Neuropterida), especially on coleopteran taxa considered as potential close relatives of Strepsiptera. Using models robust against the long branch attraction artifact we find a highly resolved phylogeny that confirms the position of Strepsiptera as a sister group to Coleoptera, rather than as an internal clade of Coleoptera, and sheds new light onto the phylogeny of Neuropteroidea. PMID:25272037
Combining Alphas via Bounded Regression
Directory of Open Access Journals (Sweden)
Zura Kakushadze
2015-11-01
Full Text Available We give an explicit algorithm and source code for combining alpha streams via bounded regression. In practical applications, typically, there is insufficient history to compute a sample covariance matrix (SCM for a large number of alphas. To compute alpha allocation weights, one then resorts to (weighted regression over SCM principal components. Regression often produces alpha weights with insufficient diversification and/or skewed distribution against, e.g., turnover. This can be rectified by imposing bounds on alpha weights within the regression procedure. Bounded regression can also be applied to stock and other asset portfolio construction. We discuss illustrative examples.
Bounded Rationality and the Diffusion of Modern Investment Treaties
DEFF Research Database (Denmark)
Skovgaard Poulsen, Lauge
2014-01-01
insights on cognitive heuristics. In line with recent work on policy diffusion, it suggests that a bounded rationality framework has considerable potential to explain why, and how, developing countries have adopted modern investment treaties. To illustrate the potential of this approach, the case of South...
Soffer bound and transverse spin densities from lattice QCD
International Nuclear Information System (INIS)
Generalized transversity distributions encode essential information on the internal structure of hadrons related to transversely polarized quarks. Lattice QCD allows us to compute the lowest moments of these tensor generalized parton distributions. In this talk, we discuss a first lattice study of the Soffer bound and show preliminary results for transverse spin densities of quarks in the nucleon. (orig.)
Key management and encryption under the bounded storage model.
Energy Technology Data Exchange (ETDEWEB)
Draelos, Timothy John; Neumann, William Douglas; Lanzone, Andrew J.; Anderson, William Erik
2005-11-01
There are several engineering obstacles that need to be solved before key management and encryption under the bounded storage model can be realized. One of the critical obstacles hindering its adoption is the construction of a scheme that achieves reliable communication in the event that timing synchronization errors occur. One of the main accomplishments of this project was the development of a new scheme that solves this problem. We show in general that there exist message encoding techniques under the bounded storage model that provide an arbitrarily small probability of transmission error. We compute the maximum capacity of this channel using the unsynchronized key-expansion as side-channel information at the decoder and provide tight lower bounds for a particular class of key-expansion functions that are pseudo-invariant to timing errors. Using our results in combination with Dziembowski et al. [11] encryption scheme we can construct a scheme that solves the timing synchronization error problem. In addition to this work we conducted a detailed case study of current and future storage technologies. We analyzed the cost, capacity, and storage data rate of various technologies, so that precise security parameters can be developed for bounded storage encryption schemes. This will provide an invaluable tool for developing these schemes in practice.
Speed of sound bounds and neutron star structure
Moustakidis, Ch C; Margaritis, Ch; Lalazissis, G A
2016-01-01
The accurate determination of the maximum mass of the neutron stars is one of the most important tasks in Astrophysics. It is directly related with the identification of the black holes in the Universe, the production of neutron stars from the supernovae explosion and the Equation of State (EoS) of dense matter. However, not only the EoS is directly connected with neutron star masses, but also the speed of sound in dense matter is a crucial quantity which characterizes the stiffness of the EoS. The upper bound of the speed of sound imposes strong constraints on the maximum mass of neutron stars. However, this upper bound remains still an open issue. Recent observations, of binary neutron star systems, offer the possibility to measure with high accuracy both the mass and the tidal polarizability of the stars. We study possible effects of the upper bound of the speed of sound on the upper bound of the mass and the tidal polarizability. We conclude that this kind of measurements, combined with recent observation...
Modified Lyth bound and implications of BICEP2 results
Gao, Qing; Li, Tianjun
2015-01-01
To reconcile the BICEP2 measurement on the tensor-to-scalar ratio $r$ with Planck constraint, a large negative running of scalar spectral index $n_s$ is needed. So the inflationary observable such as $n_s$ should be expanded at least to the second-order slow-roll parameters for single-field inflationary models. The large value of $r$ and the Lyth bound indicate that it is impossible to obtain the sub-Planckian excursion for the inflaton. However, we derive an absolutely minimal bound $\\Delta\\phi/M_{\\rm Pl}>\\sqrt{r/2}$ on the inflaton excursion for single-field inflationary models, which can be applied to non-slow-roll inflationary models as well. This bound excludes the possibility of the small-field inflation with $\\Delta\\phi<0.1 M_{\\rm Pl}$ if the BICEP2 result on $r$ stands and it opens the window of sub-Planckian excursion with $\\Delta\\phi
On a branch-and-bound approach for a Huff-like Stackelberg location problem
Sáiz Pérez, M.E.; Hendrix, E.M.T.; Fernández, J.; Pelegrin, B.
2009-01-01
Modelling the location decision of two competing firms that intend to build a new facility in a planar market can be done by a Huff-like Stackelberg location problem. In a Huff-like model, the market share captured by a firm is given by a gravity model determined by distance calculations to faciliti
Scheduling Packets with Values and Deadlines in Size-bounded Buffers
Li, Fei
2010-01-01
Motivated by providing quality-of-service differentiated services in the Internet, we consider buffer management algorithms for network switches. We study a multi-buffer model. A network switch consists of multiple size-bounded buffers such that at any time, the number of packets residing in each individual buffer cannot exceed its capacity. Packets arrive at the network switch over time; they have values, deadlines, and designated buffers. In each time step, at most one pending packet is allowed to be sent and this packet can be from any buffer. The objective is to maximize the total value of the packets sent by their respective deadlines. A 9.82-competitive online algorithm has been provided for this model (Azar and Levy. SWAT 2006), but no offline algorithms have been known yet. In this paper, We study the offline setting of the multi-buffer model. Our contributions include a few optimal offline algorithms for some variants of the model. Each variant has its unique and interesting algorithmic feature. Thes...
Branching Out: Rhodium-Catalyzed Allylation with Alkynes and Allenes.
Koschker, Philipp; Breit, Bernhard
2016-08-16
We present a new and efficient strategy for the atom-economic transformation of both alkynes and allenes to allylic functionalized structures via a Rh-catalyzed isomerization/addition reaction which has been developed in our working group. Our methodology thus grants access to an important structural class valued in modern organic chemistry for both its versatility for further functionalization and the potential for asymmetric synthesis with the construction of a new stereogenic center. This new methodology, inspired by mechanistic investigations by Werner in the late 1980s and based on preliminary work by Yamamoto and Trost, offers an attractive alternative to other established methods for allylic functionalization such as allylic substitution or allylic oxidation. The main advantage of our methodology consists of the inherent atom economy in comparison to allylic oxidation or substitution, which both produce stoichiometric amounts of waste and, in case of the substitution reaction, require prefunctionalization of the starting material. Starting out with the discovery of a highly branched-selective coupling reaction of carboxylic acids with terminal alkynes using a Rh(I)/DPEphos complex as the catalyst system, over the past 5 years we were able to continuously expand upon this chemistry, introducing various (pro)nucleophiles for the selective C-O, C-S, C-N, and C-C functionalization of both alkynes and the double-bond isomeric allenes by choosing the appropriate rhodium/bidentate phosphine catalyst. Thus, valuable compounds such as branched allylic ethers, sulfones, amines, or γ,δ-unsaturated ketones were successfully synthesized in high yields and with a broad substrate scope. Beyond the branched selectivity inherent to rhodium, many of the presented methodologies display additional degrees of selectivity in regard to regio-, diastereo-, and enantioselective transformations, with one example even proceeding via a dynamic kinetic resolution. Many advances
Structure and Hydration of Highly Branched, Monodisperse Phytoglycogen Nanoparticles
Atkinson, John; Nickels, Jonathan; Stanley, Christopher; Diallo, Souleymane; Katsaras, John; Dutcher, John
Monodisperse phytoglycogen nanoparticles are a promising, new soft colloidal nanomaterial with many applications in the personal care, food, nutraceutical and pharmaceutical industries. These applications rely on exceptional properties that emerge from the highly branched structure of phytoglycogen and its interaction with water, such as extraordinarily high water retention, and low viscosity and exceptional stability in water. The structure and hydration of the nanoparticles was characterized using small angle neutron scattering (SANS) and quasielastic neutron scattering (QENS). SANS allowed us to determine the size of the nanoparticles, evaluate their radial density profile, quantify the particle-to-particle spacing, and determine their water content. The results show clearly that the nanoparticles are highly hydrated, with each nanoparticle containing 250% of its mass in water, and that aqueous dispersions approach a jamming transition at ~ 25% (w/w). QENS experiments provided an independent and consistent measure of the high level of hydration of the particles.
Combined branch retinal vein and artery occlusion in toxoplasmosis.
Aggio, Fabio Bom; Novelli, Fernando José de; Rosa, Evandro Luis; Nobrega, Mário Junqueira
2016-01-01
A 22-year-old man complained of low visual acuity and pain in his left eye for five days. His ophthalmological examination revealed 2+ anterior chamber reaction and a white, poorly defined retinal lesion at the proximal portion of the inferotemporal vascular arcade. There were retinal hemorrhages in the inferotemporal region extending to the retinal periphery. In addition, venous dilation, increased tortuosity, and ischemic retinal whitening along the inferotemporal vascular arcade were also observed. A proper systemic work-up was performed, and the patient was diagnosed with ocular toxoplasmosis. He was treated with an anti-toxoplasma medication, and his condition slowly improved. Inferior macular inner and middle retinal atrophy could be observed on optical coherence tomography as a sequela of ischemic injury. To our knowledge, this is the first report of combined retinal branch vein and artery occlusion in toxoplasmosis resulting in a striking and unusual macular appearance. PMID:27463632
Side Branch Interaction with Main Line Standing Waves and Related Signal Handling Approaches
Directory of Open Access Journals (Sweden)
Arthur Ruggles
2013-01-01
Full Text Available Data from a low pressure air test facility are used to quantify the influence of the acoustic field in the main line on side branch resonance behavior. The main line of diameter = 7.6 cm may accumulate acoustic energy broadcast from a resonating branch of diameter = 1.9 cm ( = 0.25. The side branch resonance amplitude is a strong function of branch position along the main line with the normalized pressure rising to 1.2 in the most favorable branch positions with Strouhal number near 0.3. Large time variation of the side branch and main line resonance amplitude is apparent for most branch positions. A moving window is used on the time history to collect an array of power spectral densities (PSDs. Peak amplitude values from the PSD array are represented in a probability density function (PDF that provides a repeatable characterization of data from the system.
Open string multi-branched and Kahler potentials
Carta, Federico; Staessens, Wieland; Zoccarato, Gianluca
2016-01-01
We consider type II string compactifications on Calabi-Yau orientifolds with fluxes and D-branes, and analyse the F-term scalar potential that simultaneously involves closed and open string modes. In type IIA models with D6-branes such potential can be directly computed by integrating out Minkowski three-forms. The result shows a multi-branched structure along the space of lifted open string moduli, in which discrete shifts in special Lagrangian and Wilson line deformations are compensated by changes in the RR flux quanta. The same sort of discrete shift symmetries are present in the superpotential and constrain the Kahler potential. As for the latter, inclusion of open string moduli breaks the factorisation between complex structure and Kahler moduli spaces. Nevertheless, the 4d Kahler metrics display a set of interesting relations that allow to rederive the scalar potential analytically. Similar results hold for type IIB flux compactifications with D7-brane Wilson lines.
Diterpenoids from the branch and leaf of Abies fargesii.
Wu, Wen-Ming; Liu, Ye; Chen, Xu; Jin, An; Zhou, Ming; Tian, Tian; Ruan, Han-Li
2016-04-01
Five new abietane diterpenoids, named abifadines A-E (1-5), and nine known ones (6-14), together with two known podocarpenes (15 and 16), were isolated from the branch and leaf of Abies fargesii. Their structures including the relative configurations were established on the basis of extensive spectroscopic analyses. The absolute configuration of 1 was determined through single-crystal X-ray diffraction analysis with Cu Kα irradiation. All the isolates were evaluated for their in vitro cytotoxicities. Only compounds 5 and 12 exhibited weak anti-proliferative effects against three cancer cell lines (B16, MCF7, and HepG2) with IC50 values range from 14.8 to 42.8 μM. The antimicrobial activities against Staphylococcus aureus, Escherichia coli and Monilia albicans of all compounds were also tested, but none of them showed significant activities. PMID:26969787
Branching exponential flights: travelled lengths and collision statistics
International Nuclear Information System (INIS)
The evolution of several physical and biological systems, ranging from neutron transport in multiplying media to epidemics or population dynamics, can be described in terms of branching exponential flights, a stochastic process which couples a Galton–Watson birth–death mechanism with random spatial displacements. Within this context, one is often called to assess the length ℓV that the process travels in a given region V of the phase space, or the number of visits nV to this same region. In this paper, we address this issue by resorting to the Feynman–Kac formalism, which allows characterizing the full distribution of ℓV and nV and in particular deriving explicit moment formulas. Some other significant physical observables associated to ℓV and nV, such as the survival probability, are discussed as well, and results are illustrated by revisiting the classical example of the rod model in nuclear reactor physics. (paper)
Macular edema in branch retinal vein occlusion: types and treatment.
Jalkh, A E; Trempe, C L
1989-01-01
In this study of branch retinal vein occlusion, we distinguished between cystoid macular edema caused by increased capillary pressure and noncystoid edema due to hard exudates in the macula caused by chronic leakage from vascular abnormalities in the posterior pole or midperiphery. We performed laser photocoagulation in 51 eyes with cystoid macular edema to achieve focal narrowing of the retinal arterioles perfusing the macular area affected by the cystoid edema; good anatomic and functional results were achieved in 40 of these eyes (78%). In 25 of the five eyes, the treated segment of the retinal arteriole was outside the area of macular edema; results were successful in 19 of these eyes (76%). In 14 eyes with noncystoid exudative macular edema, we performed laser photocoagulation to the vascular abnormalities; good anatomic and functional results were obtained in 12 of these (86%). PMID:2927879
Q-branch Raman scattering and modern kinetic thoery
Energy Technology Data Exchange (ETDEWEB)
Monchick, L. [The Johns Hopkins Univ., Laurel, MD (United States)
1993-12-01
The program is an extension of previous APL work whose general aim was to calculate line shapes of nearly resonant isolated line transitions with solutions of a popular quantum kinetic equation-the Waldmann-Snider equation-using well known advanced solution techniques developed for the classical Boltzmann equation. The advanced techniques explored have been a BGK type approximation, which is termed the Generalized Hess Method (GHM), and conversion of the collision operator to a block diagonal matrix of symmetric collision kernels which then can be approximated by discrete ordinate methods. The latter method, which is termed the Collision Kernel method (CC), is capable of the highest accuracy and has been used quite successfully for Q-branch Raman scattering. The GHM method, not quite as accurate, is applicable over a wider range of pressures and has proven quite useful.
Institute of Scientific and Technical Information of China (English)
李改弟; 王真; 吴裕林
2013-01-01
We study the lower-bounded facility location problem with penalties (LBFLP) and the soft-capacity LBFLP.For the LBFLP,we present an updated bicriteria approximation algorithm which maintains the same performance factor (1+α)/(1-α)ρ as that for the problem without penalties in Hierarchical placement and network design problems (Guha S,Meyerson A,Munagala K.Hierarchical placement and network design problems [C]/ / Proceedings of Foundations of Computer Science,2000:892328,DOI:10.1109/SFC-S.2000.892328) and Building steiner trees with incomplete global knowledge (Karger D R,Minkoff M.Building steiner trees with incomplete global knowledge [C]//Proceedings of Foundations of Computer Science,2000:892329,DOI:10.1109/SFCS.2000.892329).We further extend this result to the soft-capacitated LBFLP and achieve a performance factor twice as much as that for LBFLP.%研究带惩罚和软容量约束的下界设施选址问题.扩展Guha等(Guha S,Meyerson A,Munagala K.Hierarchical placement and network design problems [C]//Proceedings of Foundations of Computer Science,2000:892328,DOI:10.1109/SFCS.2000.892328)和Karger等(Karger D R,Minkoff M.Building steiner trees with incomplete global knowledge [C]//Proceedings of Foundations of Computer Science,2000:892329,DOI:10.1109/SFCS.2000.892329)的工作到带有惩罚的下界约束设施选址问题,提出了一个新的双标准近似算法,得到了同样的近似比(1+α)/(1-α)ρ.进一步考虑带惩罚和软容量约束的下界设施选址问题,得到了近似比为2(1+α)/(1-α)ρ的双标准近似算法.
Directory of Open Access Journals (Sweden)
Peng Li
2014-11-01
Full Text Available In vehicular ad hoc networks, roadside units (RSUs placement has been proposed to improve the the overall network performance in many ITS applications. This paper addresses the budget constrained and delay-bounded placement problem (BCDP for roadside units in vehicular ad hoc networks. There are two types of RSUs: cable connected RSU (c-RSU and wireless RSU (w-RSU. c-RSUs are interconnected through wired lines, and they form the backbone of VANETs, while w-RSUs connect to other RSUs through wireless communication and serve as an economical extension of the coverage of c-RSUs. The delay-bounded coverage range and deployment cost of these two cases are totally different. We are given a budget constraint and a delay bound, the problem is how to find the optimal candidate sites with the maximal delay-bounded coverage to place RSUs such that a message from any c-RSU in the region can be disseminated to the more vehicles within the given budget constraint and delay bound. We first prove that the BCDP problem is NP-hard. Then we propose several algorithms to solve the BCDP problem. Simulation results show the heuristic algorithms can significantly improve the coverage range and reduce the total deployment cost, compared with other heuristic methods.
Li, Peng; Huang, Chuanhe; Liu, Qin
2014-01-01
In vehicular ad hoc networks, roadside units (RSUs) placement has been proposed to improve the the overall network performance in many ITS applications. This paper addresses the budget constrained and delay-bounded placement problem (BCDP) for roadside units in vehicular ad hoc networks. There are two types of RSUs: cable connected RSU (c-RSU) and wireless RSU (w-RSU). c-RSUs are interconnected through wired lines, and they form the backbone of VANETs, while w-RSUs connect to other RSUs through wireless communication and serve as an economical extension of the coverage of c-RSUs. The delay-bounded coverage range and deployment cost of these two cases are totally different. We are given a budget constraint and a delay bound, the problem is how to find the optimal candidate sites with the maximal delay-bounded coverage to place RSUs such that a message from any c-RSU in the region can be disseminated to the more vehicles within the given budget constraint and delay bound. We first prove that the BCDP problem is NP-hard. Then we propose several algorithms to solve the BCDP problem. Simulation results show the heuristic algorithms can significantly improve the coverage range and reduce the total deployment cost, compared with other heuristic methods. PMID:25436656
Li, Peng; Huang, Chuanhe; Liu, Qin
2014-01-01
In vehicular ad hoc networks, roadside units (RSUs) placement has been proposed to improve the the overall network performance in many ITS applications. This paper addresses the budget constrained and delay-bounded placement problem (BCDP) for roadside units in vehicular ad hoc networks. There are two types of RSUs: cable connected RSU (c-RSU) and wireless RSU (w-RSU). c-RSUs are interconnected through wired lines, and they form the backbone of VANETs, while w-RSUs connect to other RSUs through wireless communication and serve as an economical extension of the coverage of c-RSUs. The delay-bounded coverage range and deployment cost of these two cases are totally different. We are given a budget constraint and a delay bound, the problem is how to find the optimal candidate sites with the maximal delay-bounded coverage to place RSUs such that a message from any c-RSU in the region can be disseminated to the more vehicles within the given budget constraint and delay bound. We first prove that the BCDP problem is NP-hard. Then we propose several algorithms to solve the BCDP problem. Simulation results show the heuristic algorithms can significantly improve the coverage range and reduce the total deployment cost, compared with other heuristic methods. PMID:25436656
Gutiérrez-Rodríguez, A
2003-01-01
A bound on the nu /sup tau / magnetic moment is calculated through the reaction e/sup +/e/sup -/ to nu nu gamma at the Z/sub 1/-pole, and in the framework of a left-right symmetric model at LEP energies. We find that the bound is almost independent of the mixing angle phi of the model in the allowed experimental range for this parameter. (31 refs).
Integrability and the Conformal Field Theory of the Higgs branch
Sax, Olof Ohlsson; Stefanski, Bogdan
2014-01-01
In the context of the AdS$_3$/CFT$_2$ correspondence, we investigate the CFT$_2$ at the origin of the Higgs branch. This theory has a planar, weak-coupling limit, in which anomalous dimensions of single-trace composite operators can be calculated. At one loop, the calculation reduces to finding the spectrum of a spin-chain with nearest-neighbour interactions. This CFT$_2$ spin-chain matches precisely the one that was previously found as the weak-coupling limit of the integrable system describing the AdS$_3$ side of the duality. We compute the one-loop dilatation operator in a non-trivial compact subsector and show that it corresponds to an integrable spin-chain Hamiltonian. This provides the first direct evidence of integrability on the CFT$_2$ side of the correspondence.
P.J.M. Meersmans; A.P.M. Wagelmans (Albert)
2001-01-01
textabstractIn this paper we consider the problem of integrated scheduling of various types of handling equipment at an automated container terminal, where the objective is to minimize the makespan of the schedule. We present a Branch & Bound algorithm that uses various combinatorial lower bounds. C
Shaik, Shahnoor S; Obata, Toshihiro; Hebelstrup, Kim H; Schwahn, Kevin; Fernie, Alisdair R; Mateiu, Ramona V; Blennow, Andreas
2016-01-01
Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD. PMID:26891365
Locating-dominating codes: Bounds and extremal cardinalities
Cáceres, Jose; Hernando Martín, María del Carmen; Mora Giné, Mercè; Pelayo Melero, Ignacio Manuel; Puertas, M. Luz
2013-01-01
In this work, two types of codes such that they both dominate and locate the vertices of a graph are studied. Those codes might be sets of detectors in a network or processors controlling a system whose set of responses should determine a malfunctioning processor or an intruder. Here, we present our more significant contributions on \\lambda-codes and \\eta-codes concerning concerning bounds, extremal values and realization theorems.
Bounds on expectation values of quantum subsystems and perturbation theory
International Nuclear Information System (INIS)
The numerical investigation of many-body quantum systems usually requires different kinds of physical approximations. The error which is made by these approximations is difficult to estimate and remains unknown in most cases. We examine an upper bound on expectation values of quantum subsystems, which enables the estimation of the maximum error that is made by physical approximations outside the subsystem. This is of special interest for perturbation theory, where the bath is commonly approximated with simplified interactions. A recently realized all-spin-based atomic-scale logic device, consisting of iron atoms and cobalt islands placed on a copper substrate, serves as a specific example for an application of the bound. Strength and weakness of these methods are critically discussed and we provide a quantitative answer to the old question in which cases a small quantum system can be used instead of a large one. (paper)
Algorithms Design Techniques and Analysis
Alsuwaiyel, M H
1999-01-01
Problem solving is an essential part of every scientific discipline. It has two components: (1) problem identification and formulation, and (2) solution of the formulated problem. One can solve a problem on its own using ad hoc techniques or follow those techniques that have produced efficient solutions to similar problems. This requires the understanding of various algorithm design techniques, how and when to use them to formulate solutions and the context appropriate for each of them. This book advocates the study of algorithm design techniques by presenting most of the useful algorithm desi
Institute of Scientific and Technical Information of China (English)
Xiao-dong Wang; Ren-jie Yang
2009-01-01
Objective: To observe the presentation and variation of extrahepatic branches originating from hepatic artery by hepatic arteriography.Methods: Hepatic arteriogram of 200 cases with unresectable hepatic primary or metastatic tumors before interventional therapy were retrospectively analyzed. Two interventional radiologists independently reviewed the type, originating artery, distribution and variation of extrahepatic artery.Results: Five types of extrahepatic artery were found, with the most common type of the right gastric artery (n=156, 78%), followed by the cystic artery (n=126, 63%), accessory left gastric artery (n=19, 9.5%), hepatic falciform artery (n=5, 2.5%), and accessory left inferior phrenic artery (n=4, 2%). In 188 cases, there were extrahepatic arteries derived from hepatic proper artery or its branches, and the most frequent originating site was the right hepatic artery (130 extrahepatic branches), followed by the proper hepatic artery (103 branches), left hepatic artery (56 branches) and middle hepatic artery (3 branches). The left hepatic artery was the arising site with the multiple types of extrahepatic branches including all above branches except the cystic artery.Conclusion: Many types of extrahepatic branches usually derive from the hepatic artery or its distal branches, and its originating sites are not constant. It is important to avoid damage of extrahepatic tissue during interventional therapy for liver tumors.
ABSTRACT FUNCTIONS OF BOUNDED VARIATION AND ABSOLUTE CONTINUITY
Institute of Scientific and Technical Information of China (English)
WuCongxin; LiuTiefu
1994-01-01
As well known that in 1938,I. M. Gelfand firstly introduced abstract functions of bounded variation from [a,b] to a Banach space. After Gelfand's work,many mathematicians investigated various properties and of this kind of abstract functions, and also paid attention to the abstract functions of absolute continuity In this paper, we summarize to explain our work [1-17] about this topic.
Organizational Coordination and Costly Communication with Boundedly Rational Agents
Dietrichson, Jens; Jochem, Torsten
2014-01-01
How does costly communication affect organizational coordination? This paper develops a model of costly communication based on the weakest-link game and boundedly rational agents. Solving for the stochastically stable states, we find that communication increases the possibilities for efficient coordination compared to a setting where agents cannot communicate. But as agents face a trade-off between lowering the strategic uncertainty for the group and the costs of communication, the least effi...
Limit Shapes and Fluctuations of Bounded Random Partitions
DEFF Research Database (Denmark)
Beltoft, Dan
Young diagrams confined to a rectangle. When the rectangle grows, and diagrams are rescaled, the probability measure degenerates to a delta measure on a continuous curve, the limit shape. In the intermediate scaling, the fluctuations around the limit shape turn out to be governed by an Ornstein......-Uhlenbeck process. Similar behaviour occurs in the related models bounded only on one side or not at all, which were studied by Vershik and others....
Bounded Algebra and Current-Mode Digital Circuits
Institute of Scientific and Technical Information of China (English)
WU Xunwei; Massoud Pedram
1999-01-01
This paper proposes two boundedarithmetic operations, which are easily realized with current signals.Based on these two operations, a bounded algebra system suitable fordescribing current-mode digital circuits is developed and itsrelationship with the Boolean algebra, which is suitable for representingvoltage-mode digital circuits, is investigated. Design procedure forcurrent-mode circuits using the proposed algebra system is demonstratedon a number of common circuit elements which are used to realizearithmetic operations, such as adders and multipliers.
Young's integral inequality with upper and lower bounds
Directory of Open Access Journals (Sweden)
Douglas R. Anderson
2011-06-01
Full Text Available Young's integral inequality is reformulated with upper and lower bounds for the remainder. The new inequalities improve Young's integral inequality on all time scales, such that the case where equality holds becomes particularly transparent in this new presentation. The corresponding results for difference equations are given, and several examples are included. We extend these results to piecewise-monotone functions as well.
The Economics of Bounded Rationality, Entrepreneurship and Institutional Evolution
Day, Richard H.
1989-01-01
Bounded rationality provides a fundamental economic explanation for non-rational modes of behavior. These non-rational modes underlie both the erratic perturbations of entrepreneurship and the systematic waves of diffusion they initiate which in turn guarantee that the economy operates out of equilibrium. Continuing adjustments out of equilibrium are made possible by financial intermediation. They imply asymmetric changes in individual welfare. The markets for entrepreneurship, ownership and ...
Testing and Using the Lewin-Lieb Bound in Density Functional Theory
Feinblum, David V; Burke, Kieron
2014-01-01
Lewin and Lieb have recently proven several new bounds on the exchange-correlation energy that complement the Lieb-Oxford bound. We test these bounds for atoms, for slowly-varying gases, and for Hooke's atom, finding them usually (but not always) less strict than the Lieb-Oxford bound. However, we also show that, if a GGA is to guarantee satisfaction of the new bounds for all densities, new restrictions on the the exchange-correlation enhancement factor are implied.
Communication: Testing and using the Lewin-Lieb bounds in density functional theory
International Nuclear Information System (INIS)
Lewin and Lieb have recently proven several new bounds on the exchange-correlation energy that complement the Lieb-Oxford bound. We test these bounds for atoms, for slowly-varying gases, and for Hooke’s atom, finding them usually less strict than the Lieb-Oxford bound. However, we also show that, if a generalized gradient approximation is to guarantee satisfaction of the new bounds for all densities, new restrictions on the exchange-correlation enhancement factor are implied
Parallel algorithms and architecture for computation of manipulator forward dynamics
Fijany, Amir; Bejczy, Antal K.
1989-01-01
Parallel computation of manipulator forward dynamics is investigated. Considering three classes of algorithms for the solution of the problem, that is, the O(n), the O(n exp 2), and the O(n exp 3) algorithms, parallelism in the problem is analyzed. It is shown that the problem belongs to the class of NC and that the time and processors bounds are of O(log2/2n) and O(n exp 4), respectively. However, the fastest stable parallel algorithms achieve the computation time of O(n) and can be derived by parallelization of the O(n exp 3) serial algorithms. Parallel computation of the O(n exp 3) algorithms requires the development of parallel algorithms for a set of fundamentally different problems, that is, the Newton-Euler formulation, the computation of the inertia matrix, decomposition of the symmetric, positive definite matrix, and the solution of triangular systems. Parallel algorithms for this set of problems are developed which can be efficiently implemented on a unique architecture, a triangular array of n(n+2)/2 processors with a simple nearest-neighbor interconnection. This architecture is particularly suitable for VLSI and WSI implementations. The developed parallel algorithm, compared to the best serial O(n) algorithm, achieves an asymptotic speedup of more than two orders-of-magnitude in the computation the forward dynamics.
Branching innovation, recombinant innovation, and endogenous technological transitions
Frenken, K.; Izquierdo, L.; Zeppini, P.
2012-01-01
We propose a model of technological transitions based on two different types of innovations. Branching innovations refer to technological improvements along a particular path, while recombinant innovations represent fusions of multiple paths. Recombinant innovations create "short-cuts" which reduce
Linearly Bounded Liars, Adaptive Covering Codes, and Deterministic Random Walks
Cooper, Joshua N
2009-01-01
We analyze a deterministic form of the random walk on the integer line called the {\\em liar machine}, similar to the rotor-router model, finding asymptotically tight pointwise and interval discrepancy bounds versus random walk. This provides an improvement in the best-known winning strategies in the binary symmetric pathological liar game with a linear fraction of responses allowed to be lies. Equivalently, this proves the existence of adaptive binary block covering codes with block length $n$, covering radius $\\leq fn$ for $f\\in(0,1/2)$, and cardinality $O(\\sqrt{\\log \\log n}/(1-2f))$ times the sphere bound $2^n/\\binom{n}{\\leq \\lfloor fn\\rfloor}$.
Campbell, Bruce G.; Landmeyer, James E.
2014-01-01
Chesterfield County is located in the northeastern part of South Carolina along the southern border of North Carolina and is primarily underlain by unconsolidated sediments of Late Cretaceous age and younger of the Atlantic Coastal Plain. Approximately 20 percent of Chesterfield County is in the Piedmont Physiographic Province, and this area of the county is not included in this study. These Atlantic Coastal Plain sediments compose two productive aquifers: the Crouch Branch aquifer that is present at land surface across most of the county and the deeper, semi-confined McQueen Branch aquifer. Most of the potable water supplied to residents of Chesterfield County is produced from the Crouch Branch and McQueen Branch aquifers by a well field located near McBee, South Carolina, in the southwestern part of the county. Overall, groundwater availability is good to very good in most of Chesterfield County, especially the area around and to the south of McBee, South Carolina. The eastern part of Chesterfield County does not have as abundant groundwater resources but resources are generally adequate for domestic purposes. The primary purpose of this study was to determine groundwater-flow rates, flow directions, and changes in water budgets over time for the Crouch Branch and McQueen Branch aquifers in the Chesterfield County area. This goal was accomplished by using the U.S. Geological Survey finite-difference MODFLOW groundwater-flow code to construct and calibrate a groundwater-flow model of the Atlantic Coastal Plain of Chesterfield County. The model was created with a uniform grid size of 300 by 300 feet to facilitate a more accurate simulation of groundwater-surface-water interactions. The model consists of 617 rows from north to south extending about 35 miles and 884 columns from west to east extending about 50 miles, yielding a total area of about 1,750 square miles. However, the active part of the modeled area, or the part where groundwater flow is simulated
Fundamentals of natural computing basic concepts, algorithms, and applications
de Castro, Leandro Nunes
2006-01-01
Introduction A Small Sample of Ideas The Philosophy of Natural Computing The Three Branches: A Brief Overview When to Use Natural Computing Approaches Conceptualization General Concepts PART I - COMPUTING INSPIRED BY NATURE Evolutionary Computing Problem Solving as a Search Task Hill Climbing and Simulated Annealing Evolutionary Biology Evolutionary Computing The Other Main Evolutionary Algorithms From Evolutionary Biology to Computing Scope of Evolutionary Computing Neurocomputing The Nervous System Artif