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In many resource allocation problems, a centralized controller needs to award some resource to a user selected from a collection of distributed users with the goal of maximizing the utility the user would receive from the resource. This can be modeled as the controller computing an extremum of the distributed users' utilities. The overhead rate necessary to enable the controller to reproduce the users' local state can be prohibitively high. An approach to reduce this overhead is interactive communication wherein rate savings are achieved by tolerating an increase in delay. In this paper, we consider the design of a simple achievable scheme based on successive refinements of scalar quantization at each user. The optimal quantization policy is computed via a dynamic program and we demonstrate that tolerating a small increase in delay can yield significant rate savings. We then consider two simpler quantization policies to investigate the scaling properties of the rate-delay trade-offs. Using a combination of these simpler policies, the performance of the optimal policy can be closely approximated with lower computational costs., Comment: 31 pages, 9 figures. Submitted on 2015-05-15 to IEEE Transactions on Signal Processing. Revised 2015-09-06

A key aspect of many resource allocation problems is the need for the resource controller to compute a function, such as the max or arg max, of the competing users metrics. Information must be exchanged between the competing users and the resource controller in order for this function to be computed. In many practical resource controllers the competing users' metrics are communicated to the resource controller, which then computes the desired extremization function. However, in this paper it is shown that information rate savings can be obtained by recognizing that controller only needs to determine the result of this extremization function. If the extremization function is to be computed losslessly, the rate savings are shown in most cases to be at most 2 bits independent of the number of competing users. Motivated by the small savings in the lossless case, simple achievable schemes for both the lossy and interactive variants of this problem are considered. It is shown that both of these approaches have the potential to realize large rate savings, especially in the case where the number of competing users is large. For the lossy variant, it is shown that the proposed simple achievable schemes are in fact close to the fundamental limit given by the rate distortion function., Comment: 70 pages, 18 figures, Submitted to IEEE Transactions on Information Theory on 2014-08-14

We consider the optimal transmission of distributed correlated discrete memoryless sources across a network with capacity constraints. We present several previously undiscussed structural properties of the set of feasible rates and transmission schemes. We extend previous results concerning the intersection of polymatroids and contrapolymatroids to characterize when all of the vertices of the Slepian-Wolf rate region are feasible for the capacity constrained network. An explicit relationship between the conditional independence relationships of the distributed sources and the number of vertices for the Slepian-Wolf rate region are given. These properties are then applied to characterize the optimal transmission rate and scheme and its connection to the corner points of the Slepian-Wolf rate region. In particular, we demonstrate that when the per-source compression costs are in tension with the per-link flow costs the optimal flow/rate point need not coincide with a vertex of the Slepian-Wolf rate region. Finally, we connect results for the single-sink problem to the multi-sink problem by extending structural insights and developing upper and lower bounds on the optimal cost of the multi-sink problem., Comment: 15 pages, 13 figures, Submitted to IEEE/ACM Transactions on Networking on 2014-07-16. Correction to Fig. 13. Fixed minor typos

Concept map structure, testing, and scoring methods are discussed and a new scoring methodology is introduced using the breadth and depth of individual concept maps. The scoring method proposed here provides advantages of grading "on a curve" such as the ability to estimate and compare the complexity of different concept maps, the ability to measure the statistical distance between individual map scores, the ability to define map-score quantiles, a reduction in grading bias, and an overall improvement in the reliability and validity of concept map evaluation. Empirical support for underlying probability distributions is presented and mathematical aspects are discussed. Tables of concept map score distributions for one branch and one node are provided and may be used to very quickly assign concept map scores based on one branch and one node. (Contains 7 tables and 3 figures.) [The research for this paper was funded in part by a grant from the Academic Information Technology Committee for Academic Initiatives, Florida Institute of Technology, Fall 2003.]

The development and validation of the Math Affect Trait Questionnaire (MATQ) for the investigation of affect during mathematical problem solving is presented. Anxiety, math interest, and self-esteem under problem solving conditions are the main constructs measured by the MATQ. The instrument validation process revealed that problem correctness interacted with the relationship between math interest and self-esteem, and also interacted with the relationship between math interest and locus of control. Results highlight what may be the beginning of a vicious cycle where interested but struggling students loose self-esteem, attribute their difficulties to circumstances beyond their control, and eventually loose interest in math. The Math Affect Trait Questionnaire is a viable instrument which may be used to investigate areas involving math affect traits and their influences on problem solving. (Contains 11 references.) (Author/ASK)

The importance of emotion in problem solving is well established. The Emotion Questionnaire, presented here, is a 38 item instrument designed to measure important aspects of emotion problem solving. The development and validation of the Emotion Questionnaire is discussed. Specific results gleaned in developing and validating this instrument are reviewed. These results support Polya's theory of emotion during mathematical problem solving. (Contains 27 references.) (Author/ASK)

Mandler's (1984) model of emotion is summarized in this paper and is operatonalized analytically and statistically using Thom's (1975) catastrophe theory. Data were collected from (n=15) mathematics majors in a pilot study to test Mandler's model and the nonlinear effects of emotions in solving mathematical problems. The data were found to fit Thom's cusp model almost twice as well as the conventional linear model, thus strongly supporting Mandler's model. The implications of these findings are discussed in terms of mathematical problem solving and mathematics education. Contains 69 references. (Author/MKR)

Cobb's Cusp Surface Analysis Program (CUSP) provides a way to estimate empirically and test a nonlinear cusp catastrophe model. A model of emotion during problem solving is used to introduce catastrophe theory modeling and is discussed in conjunction with how to run and interpret CUSP. (SLD)

XMbodyinfo was designed to evaluate potential reference trajectories, providing a proficient way to assess the quality of all satellite body flybys for a Cassini type mission tour. It is autonomous and will generate a variety of ORS (optical remote sensing) and FPW (fields, particles, and waves) plots that aid in the evaluation, qualification, selection, and improvement of a potential tour.

TOAD Gateway is interactive software tool for converting data files to and from variety of file formats. Currently reads and writes following file formats: TOAD; Standard Interface File (SIF); Program to Optimize Simulated Trajectories (POST) input; Comma Separated Value and Tab Separated Value, common in PC and Macintosh spreadsheet and database packages; and general free format. Additional modules for accommodating other formats easily developed and installed. Companion program, TOAD Editor (LAR-14423), manipulates contents of TOAD files and extracts selected subsets of data. TOAD Gateway written in FORTRAN 77.

Transferable Output ASCII Data (TOAD) computer program (LAR-13755), implements format designed to facilitate transfer of data across communication networks and dissimilar host computer systems. Any data file conforming to TOAD format standard called TOAD file. TOAD Editor is interactive software tool for manipulating contents of TOAD files. Commonly used to extract filtered subsets of data for visualization of results of computation. Also offers such user-oriented features as on-line help, clear English error messages, startup file, macroinstructions defined by user, command history, user variables, UNDO features, and full complement of mathematical statistical, and conversion functions. Companion program, TOAD Gateway (LAR-14484), converts data files from variety of other file formats to that of TOAD. TOAD Editor written in FORTRAN 77.

A computer code for modeling the large angle transient dynamics (LATDYN) of structures was developed to investigate techniques for analyzing flexible deformation and control/structure interaction problems associated with large angular motions of spacecraft. This type of analysis is beyond the routine capability of conventional analytical tools without simplifying assumptions. In some instances, the motion may be sufficiently slow and the spacecraft (or component) sufficiently rigid to simplify analyses of dynamics and controls by making pseudo-static and/or rigid body assumptions. The LATDYN introduces a new approach to the problem by combining finite element structural analysis, multi-body dynamics, and control system analysis in a single tool. It includes a type of finite element that can deform and rotate through large angles at the same time, and which can be connected to other finite elements either rigidly or through mechanical joints. The LATDYN also provides symbolic capabilities for modeling control systems which are interfaced directly with the finite element structural model. Thus, the nonlinear equations representing the structural model are integrated along with the equations representing sensors, processing, and controls as a coupled system.

The Transferable Output ASCII Data (TOAD) Gateway, release 1.0 is described. This is a software tool for converting tabular data from one format into another via the TOAD format. This initial release of the Gateway allows free data interchange among the following file formats: TOAD; Standard Interface File (SIF); Program to Optimize Simulated Trajectories (POST) input; Comma Separated Value (TSV); and a general free-form file format. As required, additional formats can be accommodated quickly and easily.

The Transferable Output ASCII Data (TOAD) editor is an interactive software tool for manipulating the contents of TOAD files. The TOAD editor is specifically designed to work with tabular data. Selected subsets of data may be displayed to the user's screen, sorted, exchanged, duplicated, removed, replaced, inserted, or transferred to and from external files. It also offers a number of useful features including on-line help, macros, a command history, an 'undo' option, variables, and a full compliment of mathematical functions and conversion factors. Written in ANSI FORTRAN 77 and completely self-contained, the TOAD editor is very portable and has already been installed on SUN, SGI/IRIS, and CONVEX hosts.

The Analytic Patch Configuration (APC) is an interactive software tool which translates aircraft configuration geometry files from one format into another. This initial release of the APC Gateway accommodates six formats: the four accepted APC formats (89f, 89fd, 89u, and 89ud), the PATRAN 2.x phase 1 neutral file format, and the Integrated Aerodynamic Analysis System (IAAS) General Geometry (GG) format. Written in ANSI FORTRAN 77 and completely self-contained, the APC Gateway is very portable and was already installed on CDC/NOS, VAX/VMS, SUN, SGI/IRIS, CONVEX, and GRAY hosts.

The Pressure Visualization (PreViz) package is a software tool which merges a wireframe model of the test aircraft with pressure data represented as a series of displacement vectors normal to the aircraft's skin. The PreViz package automates much of the researcher's data reduction effort, reduces the time required to review large amounts of pressure data, presents the data more clearly than tabular listings, and provides a wireframe description for a black and white graphic suitable for a technical publication (the actual graphic images must be created by a local package since PreViz has no graphics capability). Although designed for pressure data, the PreViz package works equally well for any surface property (such as structural loading or skin temperature). Written in ANSI-standard FORTRAN 77 and self-contained, PreViz executes in UNIX, VAX/VMS, and CDC/NOS host environments.

The Cockpit Oriented Display of Aircraft Configurations (CODAC) package is an interactive FORTRAN 77 graphics program which produces high quality publication grade hidden line images of three dimensional wireframe objects. The term, Cockpit Oriented, is used because CODAC rotates objects relative to the changing aircraft axis system (rather than about a fixed global axis system) and uses the more familiar directions of yaw, roll, and pitch. In addition, CODAC accepts geometry data in a variety of formats (LaWGS, Craidon, Hess, and FVS data check), and automatically selects the appropriate panel driver. Finally, CODAC makes full use of the Precision Visuals' DI-3000 metafile option, allowing users to save, edit, and print images for group presentations or research publications.

The value of improving information for forecasting future crop harvests was investigated. Emphasis was placed upon establishing practical evaluation procedures firmly based in economic theory. The analysis was applied to the case of U.S. domestic wheat consumption. Estimates for a cost of storage function and a demand function for wheat were calculated. A model of market determinations of wheat inventories was developed for inventory adjustment. The carry-over horizon is computed by the solution of a nonlinear programming problem, and related variables such as spot and future price at each stage are determined. The model is adaptable to other markets. Results are shown to depend critically on the accuracy of current and proposed measurement techniques. The quantitative results are presented parametrically, in terms of various possible values of current and future accuracies.

The results of an investigation of the value of improving information for forecasting future crop harvests are described. A theoretical model is developed to calculate the value of increased speed of availablitiy of that information. The analysis of U.S. domestic wheat consumption was implemented. New estimates of a demand function for wheat and of a cost of storage function were involved, along with a Monte Carlo simulation for the wheat spot and future markets and a model of market determinations of wheat inventories. Results are shown to depend critically on the accuracy of current and proposed measurement techniques.