Open problems on GKK tau-matrices

We propose several open problems on GKK tau-matrices raised by examples showing that some such matrices are unstableComment: To appear in Linear Algebra and its Applications (LAA

Prepare for the Expected Worst: Algorithms for Reconfigurable Resources Under Uncertainty

In this paper we study how to optimally balance cheap inflexible resources with more expensive, reconfigurable resources despite uncertainty in the input problem. Specifically, we introduce the MinEMax model to study "build versus rent" problems. In our model different scenarios appear independently. Before knowing which scenarios appear, we may build rigid resources that cannot be changed for different scenarios. Once we know which scenarios appear, we are allowed to rent reconfigurable but expensive resources to use across scenarios. Although computing the objective in our model might seem to require enumerating exponentially-many possibilities, we show it is well estimated by a surrogate objective which is representable by a polynomial-size LP. In this surrogate objective we pay for each scenario only to the extent that it exceeds a certain threshold. Using this objective we design algorithms that approximately-optimally balance inflexible and reconfigurable resources for several NP-hard covering problems. For example, we study variants of minimum spanning and Steiner trees, minimum cuts, and facility location. Up to constants, our approximation guarantees match those of previously-studied algorithms for demand-robust and stochastic two-stage models. Lastly, we demonstrate that our problem is sufficiently general to smoothly interpolate between previous demand-robust and stochastic two-stage problems

Recommended procedure for the computation of rights of way

This thesis sets forth a recommended procedure for the computation of areas included in rights of way, using the principle of double meridian distances. For a considerable number of years, it has been the opinion of the author that steps should be taken to arrive at some form of standardization in the procedures necessary in the computation of areas involving right of way and to more or less standardize legal descriptions pertaining thereto. One need only examine the records of the various County Recorders in one particular state or in different states and he would be entirely convinced that such a need is paramount. The methods or procedures used for the computation of rights of way are almost as numerous as the number of agencies employing the same. One railway company will differ from another railway company; one public service or utility organization will differ from another public service or utility organization; the State of Missouri will differ from the State of Illinois, and the Federal Government has its own recommendations as to the correct procedure to be applied. Needless to say, this wide variation of practice leads only to confusion and may subsequently result in lost boundaries. The method and procedure set forth in this thesis was used by the author while under the employment by the State of Illinois for approximately ten years as Right of Way Engineer and is used in that state today. Although it may be a little more involved and take considerably more time than the average system used by other agencies, the ultimate result is one that will weather any type of legal action, and what is of more importance, will definitely fix points and boundaries for many generations to come --Introduction, pages 1-2

Support and reluctance in the pre-substantive phase of alleged child abuse victim investigative interviews: revised versus standard NICHD protocols.

Children's unwillingness to report abuse places them at risk for re-victimization, and interviewers who do not respond sensitively to that unwillingness may increase the likelihood that victims will not disclose abuse. Interviewer support and children's reluctance were examined on a turn-by-turn basis using sequential analyses in 199 forensic interviews of 3- to 13-year-olds who alleged maltreatment. Half of the children were interviewed using the Revised Protocol that emphasized rapport-building (RP), the others using the Standard National Institute of Child Health and Human Development Protocol (SP). When using the RP, interviewers provided proportionally more support than when using the SP, but even when using the RP they did not specifically provide support when children expressed reluctance. The RP promoted immediate cooperation when reluctant utterances were met with support, however, suggesting that supportive statements were valuable. The findings enhance our understanding of children's willingness to participate in investigative interviews and the means through which interviewers can foster the comfort and well-being of young witnesses.This research was supported by the Nuffield and Jacobs Foundations.This is the accepted manuscript. It will be embargoed until 12 months after publication. The final version is available from Wiley at http://onlinelibrary.wiley.com/doi/10.1002/bsl.2149/abstract

Teleoperator comfort and psychometric stability: Criteria for limiting master-controller forces of operation and feedback during telemanipulation

The following question is addressed: How much force should operators exert, or experience, when operating a telemanipulator master-controller for sustained periods without encountering significant fatigue and discomfort, and without loss of stability in psychometric perception of force. The need to minimize exertion demands to avoid fatigue is diametrically opposed by the need to present a wide range of force stimuli to enhance perception of applied or reflected forces. For 104 minutes subjects repetitiously performed a series of 15 s isometric pinch grasps; controlled at 5, 15, and 25 percent of their maximum voluntary strength. Cyclic pinch grasps were separated by rest intervals of 7.5 and 15 s. Upon completion of every 10 minute period, subjects interrupted grasping activities to gage the intensity of fatigue and discomfort in the hand and forearm using a cross-modal matching technique. A series of psychometric tests were then conducted to determine accuracy and stability in the subject's perception of force experienced. Results showed that onset of sensations of discomfort and fatigue were dependent upon the magnitude of grasp force, work/rest ratio, and progression of task. Declines in force magnitude estimation slopes, indicating a reduction in force perception sensitivity, occurred with increased grasp force when work/rest ratios were greater than 1.0. Specific recommendations for avoiding discomfort and shifts in force perception, by limiting pinch grasp force required for master-controller operation and range of force reflection or work/rest ratios, are provided

A comprehensive traffic survey for the city of Rolla, Phelps County, Missouri

The ultimate aim of this comprehensive traffic survey for the city of Rolla, Phelps County, Missouri, is to furnish a guide or pattern together with the necessary forms, maps and charts, that can be followed and reproduced by any city having a population of less than 10,000 in a study to determine its particular traffic problems. This survey should serve as a guide in determining what corrective action can be taken in connection with the following: (1) The improvement of location of state highway trunk [sic] routes, by-pass routes, auxiliary routes, and county roads in the city\u27s immediate area. (2) The selection and improvement of city streets that are related to highway routes, by-pass routes, auxiliary routes and county roads. (3) The improving and coordinating the city\u27s transportation system in /L. (4) Suitable parking methods or areas in the congested business district --Introduction, page 1