bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stereotypy, flexibility and coordination: key concepts in behavioral functional morphology
Authors: Wainwright Peter C. , Mehta Rita S. , Higham Timothy E. 
Published: October 2008

SUMMARY
Animal movement and its muscular control are central topics in functional morphology. As experimentalists we often manipulate stimuli in a controlled setting or compare species to observe the degree of variation in movement and motor control of particular behaviors. Understanding and communicating the biological significance of these sources of variability requires a universal terminology that is presently lacking in the functional morphology literature. We suggest that `stereotypy' be used to refer to the degree of variability observed in a behavior across trials under a given set of conditions. The ability of an organism to alter its behavior across experimental treatments is referred to as `flexibility'. We discuss how there has been a tendency to confound the phenomenon of a behavior exhibiting low variability, which we refer to as stereotyped, with inflexibility, or the inability to alter the behavior in response to a change in stimulus. The degree of stereotypy and flexibility in a behavior need not be correlated, nor need they have a common underlying basis. Coordination, a term used to describe the relationship between different body parts during movement, can be stereotyped and can show flexibility. Stereotypy of coordination can be assessed by the strength of correlations between movements of two body parts. The influence of coordination coherence on behavioral performance has rarely been considered,and could shed light on how taxa differ in their ability to perform behaviors. We suggest definitions of the terms stereotypy, flexibility and coordination,and provide examples of how and when these terms could be used when discussing behavioral changes in functional morphology.
Mother–young vocal communication and acoustic recognition promote preferential nursing in sheep
Authors: Sèbe Frédéric , Aubin Thierry , Boué Amélie , Poindron Pascal 
Published: October 2008

SUMMARYIn mammals with precocial neonates, exclusive maternal care and investment depend on mutual mother–young recognition. In sheep, this is ensured by rapid olfactory recognition of the neonate by its mother. However, recent studies suggest that other processes may participate in preferential maternal care. We investigated the possibility that acoustic communication promotes preferential nursing of the lamb. In the first of two studies, we examined the association between nursing and vocal activity in ewes and their lambs during the first 2 weeks of lactation. As early as 3 and 6 h postpartum, vocal activity was preferentially concentrated before nursing and by day 15 all vocal activity occurred within 2.5 min before nursing. In the second study, we tested the responses of ewes and lambs at 15 days postpartum to the playback of recorded bleats of their partner or from unrelated ewes and lambs. When playback was performed 30 min after a nursing episode, both ewes and lambs responded to bleats of their partner but not to bleats from alien subjects. When playback was performed 5 min after nursing, ewes did not respond to any lamb's bleats, while lambs continued responding to the bleats of their mothers, but significantly less than 30 min after nursing. Nursing therefore appears to play an important role in structuring very early vocal communication between the mother and her neonate. In turn, if the motivational state of the members of the mother–young dyad is adequate, this ensures the display of mutual acoustic recognition and prepares them for preferential nursing before maternal olfactory recognition of the lamb comes into play.
Hearing and spatial behavior in Gryllotalpa major Saussure(Orthoptera: Gryllotalpidae)
Authors: Howard Daniel R. , Mason Andrew C. , Hill Peggy S. M. 
Published: October 2008

SUMMARY
The prairie mole cricket (Gryllotalpa major Saussure) is a rare orthopteran insect of the tallgrass prairie ecosystem of the south central USA. Populations are known to currently occupy fragmented prairie sites in Oklahoma, Arkansas, Kansas and Missouri, including The Nature Conservancy's Tallgrass Prairie Preserve in north central Oklahoma. Prairie mole cricket populations were surveyed at this site and at another site in Craig County, OK during the spring of 2005 and 2006, using the male cricket's acoustic call to locate advertising aggregations of males. Five males from one large aggregation were removed in a study to describe (1) the hearing thresholds across the call's range of frequencies, (2) the distances over which the higher harmonic components of the male's calls are potentially detectable, (3)the species' sensitivity to ultrasound and (4) the spatio-auditory dynamics of the prairie mole cricket lek. Results indicate that G. major has a bimodal pattern of frequency tuning, with hearing sensitivities greatest at the 2 kHz carrier frequency (41 dB SPL) and declining through the call's frequency range (84 dB at 10 kHz). A second sensitivity peak is evident in the ultrasound range at 25 kHz (62 dB SPL). Spatial analysis of G. majorlek sites indicates that approximately 73% of males within the lek are spaced in such a way as to allow acoustic interaction at the species' carrier frequency, while any information in higher harmonic overtones in the call appears to be available only to nearest neighbors.
Metabolic costs of foraging and the management of O2 and CO2 stores in Steller sea lions
Authors: Fahlman Andreas , Svärd Caroline , Rosen David A. S. , Jones David R. , Trites Andrew W. 
Published: October 2008

SUMMARY
The metabolic costs of foraging and the management of O2 and CO2 stores during breath-hold diving was investigated in three female Steller sea lions (Eumetopias jubatus) trained to dive between 10 and 50 m (N=1142 dives). Each trial consisted of two to eight dives separated by surface intervals that were determined by the sea lion(spontaneous trials) or by the researcher (conditioned trials). During conditioned trials, surface intervals were long enough for O2 to return to pre-dive levels between each dive. The metabolic cost of each dive event (dive+surface interval; DMR) was measured using flow-through respirometry. The respiratory exchange ratio(V̇O2/V̇CO2)was significantly lower during spontaneous trials compared with conditioned trials. DMR was significantly higher during spontaneous trials and decreased exponentially with dive duration. A similar decrease in DMR was not as evident during conditioned trials. DMR could not be accurately estimated from the surface interval (SI) following individual dives that had short SIs (&lt;50 s), but could be estimated on a dive by dive basis for longer SIs (&gt;50 s). DMR decreased by 15%, but did not differ significantly from surface metabolic rates (MRS) when dive duration increased from 1 to 7 min. Overall,these data suggest that DMR is almost the same as MRS, and that Steller sea lions incur an O2 debt during spontaneous diving that is not repaid until the end of the dive bout. This has important consequences in differentiating between the actual and `apparent' metabolic rate during diving, and may explain some of the differences in metabolic rates reported in pinniped species.
Editor's Introduction
Authors: Greenberg Harvey J. 
Published: October 2008

Welcome to the inaugural issue of the ORSA Journal on Computing, dedicated to the memory of one of its founders, Robert G. Jeroslow. I wish first to thank the members of the committee established by the ORSA Computer Science Technical Section who prepared the proposal for this journal: Karla Hoffman, Robert G. Jeroslow, Donald H. Kraft, and William P. Pierskalla. Their efforts for nearly 2 years was supplemented by additional help from Thomas Magnanti. I am most grateful to them and to ORSA Council for approving this long-needed journal. Getting started is never easy, but I was fortunate to have chosen an outstanding editorial board (see inside front and back covers). Everyone helped to shape JoC's policies and obtain excellent papers to establish our scope and quality. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Parallel Numerical Optimization: Current Status and an Annotated Bibliography
Authors: Zenios Stavros A. 
Published: October 2008

Parallel computing is becoming a basic tool for research in several areas of computational mathematical programming. Algorithms and models that were intractable by the performance standards of von Neumann computers are becoming increasingly attractive. New algorithms are designed specifically for parallel architectures; the insight obtained from the design and implementation of such algorithms leads occasionally to improved sequential algorithms. Researchers report computational experiments with linear programming problems approaching a million variables and nonlinear problems with thousands of variables are solved routinely on state-of-the-art supercomputers. We classify and comment on the literature in parallel optimization with particular emphasis on the numerical and computational aspects of the field. Discussion of the parallel optimization literature is preceded by a tutorial on parallel computing in general. Work on the related areas of performance evaluation models, parallel linear algebra and benchmarks of high performance computers is presented through few representative publications. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Editor's Introduction
Authors: Greenberg Harvey J. 
Published: October 2008

We are now past initialization, and the papers in this second issue represent the diversity of the OR/CS interface. We see problems (or problem areas), like concurrent flow of information. We see pragmatics (focused on implementation), like sparse matrix techniques in implementing large-scale linear programming. We see new resources (soft and hard) for modeling and analysis, like graphics-based interfaces. We see insights into Markov chains (or general queueing processes), like reliability criteria for analysis of performance of operating systems. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Input Proofs and Rank One Cutting Planes
Authors: Hooker John N. 
Published: October 2008

Input resolution and “unit support” resolution (a generalization of unit resolution) are complete inference methods for Horn clauses in propositional logic. We show that they have a close analog in cutting plane theory. Namely, a logical clause can be deduced using input or unit support resolution if and only if it belongs to the elementary closure of the premises and is therefore a rank one cut in Chvátal's sense. This connection leads to a cutting plane algorithm for solving non-Horn inference problems. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Possibilistic Linear Programming with Measurable Multiattribute Value Functions
Authors: Inuiguchi Masahiro , Ichihashi Hidetomo , Tanaka Hideo 
Published: October 2008

In this paper, a possibilistic linear program is formulated when a measurable multiattribute value function is given. The possibilistic linear program in this paper is an unconstrained linear program with several objective functions whose coefficients are represented by possibility distributions. A possibility measure and a necessity measure are derived from a possibility distribution. Using fuzzy integrals of the measurable multiattribute value function with respect to the possibility measure and the necessity measure, the possible value and the necessary value are defined respectively. In an analogy of the expected utility, the principles of maximizing the possible value and the necessary value are considered as decision procedures under a possibility distribution. The possibilistic linear program is formulated based on these decision procedures and reduced to a nonlinear program. A solution method using linear programming technique is proposed. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
A New Estimator of Sensitivity Measures for Simulations Based on Light Traffic Theory
Authors: Simon Burton 
Published: October 2008

Consider an open queueing system that is stable for arrival rates, 0 ≤ λ < c. Let f(λ) be some function such as the mean sojourn time of a customer. Normally, light traffic theory is concerned with limits as λ → 0, e.g., f(n)(0), n = 0, 1, …. Here we use light traffic theory to obtain derivatives of f(·) at any value of λ for which the system is stable. The derivatives, f(n)(λ), n = 0, 1, …, are obtained by perturbing a system with arrival rate, λ, with a small auxiliary arrival process. The nth derivative is obtained by looking at sample paths of the original system with k auxiliary customers thrown in, k = 0, 1, …, n. In practice, the only way to obtain f(n)(λ) for λ > 0 is by observing the effect of additional customers on the sample path of a simulation. We make this technique rigorous by showing that a certain function of the sample paths is “admissible.” The analysis suggests a method for analytically bounding the derivatives, and yields a proof that a large class of queueing functions are infinitely differentiable with respect to λ. The calculations are reminiscent of other sensitivity analyses of simulations such as (infinitesimal) perturbation analysis and the likelihood ratio method. The method described here (the “light traffic perturbation method”) shares the rigorous foundation of the likelihood ratio method and numerical evidence suggests that (at least for simple systems) it has convergence properties similar to perturbation analysis. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
On the Greedy Solution of Ordering Problems
Authors: Dechter Avi , Dechter Rina 
Published: October 2008

The greedy method is a well-known approach for problem solving directed mainly at the solution of optimization problems. Leading theoretical frameworks dealing with the optimality of greedy solutions (e.g., the matroid and greedoid theories) tacitly assume that the greedy algorithm is always guided by the cost function to be optimized, namely, it builds a solution by adding, in each step, an element that contributes the most to the value of the cost function. This paper studies a class of problems for which this type of a greedy algorithm does not optimize the given cost function, but for which there exists a secondary objective function, called a greedy rule, such that applying the greedy algorithm to the secondary objective function yields a solution which is optimal with respect to the original cost function. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Editor's Introduction
Authors: Greenberg Harvey J. 
Published: October 2008

This last issue of Volume 1 reflects growing interests in the interfaces between operations research (OR) and computer science (CS). The following papers span optimization and stochastic processes; modeling and methodology; theory and application; established and uncharted topics. All this is without dichotomy, building on integration of concepts. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Series-Parallel Bounds for the Two-Terminal Reliability Problem
Authors: Aboelfotoh Hosam M. , Colbourn Charles J. 
Published: October 2008

The two-terminal reliability problem for communication networks with unreliable links is a computationally difficult problem. Upper and lower bounds can be efficiently computed using graph-theoretical techniques based on edge-packing. We present a new technique for improving these bounds via approximation by series-parallel graphs. We also present some computational results for comparison with the known edge-packing bounds. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Tabu Search—Part II
Authors: Glover Fred 
Published: October 2008

This is the second half of a two part series devoted to the tabu search metastrategy for optimization problems. Part I introduced the fundamental ideas of tabu search as an approach for guiding other heuristics to overcome the limitations of local optimality, both in a deterministic and a probabilistic framework. Part I also reported successful applications from a wide range of settings, in which tabu search frequently made it possible to obtain higher quality solutions than previously obtained with competing strategies, generally with less computational effort. Part II, in this issue, examines refinements and more advanced aspects of tabu search. Following a brief review of notation, Part II introduces new dynamic strategies for managing tabu lists, allowing fuller exploitation of underlying evaluation functions. In turn, the elements of staged search and structured move sets are characterized, which bear on the issue of finiteness. Three ways of applying tabu search to the solution of integer programming problems are then described, providing connections also to certain nonlinear programming applications. Finally, the paper concludes with a brief survey of new applications of tabu search that have occurred since the developments reported in Part I. Together with additional comparisons with other methods on a wide body of problems, these include results of parallel processing implementations and the use of tabu search in settings ranging from telecommunications to neural networks. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Reliability Computations for Planar Networks
Authors: Whited David E. , Shier Douglas R. , Jarvis James P. 
Published: October 2008

The two-terminal reliability problem for an undirected network involves calculating the probability that two distinguished sites are connected by a path of working edges. This problem is known to be NP-hard, even for the special case of planar systems. We present efficient data structures and algorithms for manipulating planar networks and for generating both paths an cutsets in such networks. A pseudopolynomial algorithm is then implemented, based on these generation procedures, to calculate two-terminal reliability for planar networks; that is, the algorithm's time complexity is polynomially bounded in the number of paths (or the number of cutsets). Computational experience with this implementation is also presented, showing that it provides a substantial improvement over previous implementations of the pseudopolynomial algorithm. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Worst-Case Analysis of Heuristics for Multidepot Capacitated Vehicle Routing Problems
Authors: Li Chung-Lun , Simchi-Levi David 
Published: October 2008

We consider the multidepot capacitated vehicle routing problems and analyze the tour partitioning heuristics for different versions of the model. We prove that the worst-case ratios of the heuristics are bounded by some fixed numbers. Examples are provided to show that the worst-case bounds are tight or asymptotically tight for almost all versions. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Matrix Visualization in the Design of Numerical Algorithms
Authors: Tuchman Allan M. , Berry Michael W. 
Published: October 2008

At the heart of much scientific computing are the algorithmic kernels often found in numerical software libraries. Numerical analysts and algorithm designers can be aided by various software tools in the design of their algorithms. We present a tool for matrix visualization and its application in the design and development of numerical algorithms for supercomputers. We discuss the development of the tool as an object-oriented distributed system and show examples of its use, including applications in linear algebra and performance monitoring. By using color computer graphics, one can gain insights into algorithm behavior, which can then be used to design more efficient numerical algorithms. In particular, we present a case study of the application of data structure visualization in the development of hybrid parallel algorithms for the singular value decomposition. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
A Neural Network Implementation of a Data Association Algorithm
Authors: Barker Allen L. , Brown Donald E. , Martin Worthy N. 
Published: October 2008

In this paper we are concerned with a time varying set of entities located in a fixed field. These entities are sensed at discrete time instances with a single sensor modality. At a given time instant a collection of bivariate Gaussian sensor reports is produced, estimating the locations of a subset of the entities present in the field. A database of reports is maintained which should ideally contain exactly one report for each entity that has been sensed. Whenever a collection of sensor reports is received the database must be updated to reflect the new information. This updating requires correspondence processing between the database reports and the new sensor reports to determine which pairs of sensor and database reports correspond to the same entity. We present an algorithm for performing this correspondence processing under the assumptions that each new collection of sensor reports contains at most one report for any entity, and that the database can be reasonably assumed to contain at most one report for any entity. This algorithm is based on pairwise distance measures between Gaussian distributions. We consider several such distance measures, and present simulation results indicating that the divergence is a reasonable choice. A formulation of the divergence between two bivariate Gaussians as a scalar product is given. We describe a neural network implementation of our algorithm, along with a proof that the network will converge and, under certain restrictions, exactly compute our correspondence algorithm. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.
Matrix Balancing on a Massively Parallel Connection Machine
Authors: Zenios Stavros A. 
Published: October 2008

Matrix balancing models find applications in economics, transportation, regional sciences, statistics, stochastic modeling and other areas. The iterative scaling algorithm RAS that is used for the solution of these problems is shown here to be suitable for data level parallelism on the Connection Machine (CM). We develop synchronous and asynchronous parallel versions of RAS and discuss designs for implementation of both dense and sparse problems on the CM. We report numerical experiences with matrices of dimension up to 1000 × 1000 and 990000 nonzero entries. Problems of this size are solved within seconds on a Connection Machine model CM-2 with 32K processing elements, and the algorithm achieves peak rate of computing in excess of 300μFLOPS. INFORMS Journal on Computing, ISSN 1091-9856, was published as ORSA Journal on Computing from 1989 to 1995 under ISSN 0899-1499.