Design of simulator training: a comparative study of Swedish dynamic decision-making training facilities

Cognition, Technology & Work - Simulator training is becoming increasingly important for training of time-critical and dynamic situations. Hence, how simulator training in such domains is...     

An Adaptive M-Estimator and Its Application to a Selection Problem

A robust adaptive estimation procedure for location estimation problems is developed. Classification in this procedure is done on the basis of skewness and tailweight, using two statistics that are ratios of linear functions of sample order statistics. The associated estimators are of the general type known as M-estimators, Following the development of the adaptive location estimation procedure, an application to the k population selection problem is given. Monte Carlo results show the superiority of the adaptive procedure to the sample means procedure, the rank sum procedure, and the previously developed adaptive procedure of Randles, Ramberg, and Hogg.     

Fostering superficial learning

Abstract Different views of learning and what it means to follow rules are discussed. The activities, the language and context of expertise and knowledge have traditionally often been neglected and underestimated as something ancillary to the real knowledge which lies ‘beyond’ such surface manifestations. The primacy of ‘superficial’ aspects are argued for. It is further argued that these should be more emphasis and fully appreciated. The goal of fostering ‘superficial’ learning is suggested, i.e. an emphasis on practical activities, the use of the language of the domain to be learned and getting familiar with the new culture. A case study is presented and discussed in terms of this theoretical viewpoint.     

Fabrication and High-Temperature Phase Stability of Mo(Al,Si)2—MoSi2 Intermetallics

A two-step processing technique was used to make dense, homogeneous intermetallics in the Mo(Al,Si)₂—MoSi₂ system. A variation of self-propagating high-temperature synthesis was used, in which starting pellets were nucleated at room temperature to make intermetallic powders from metallic precursors, followed by uniaxial hot pressing at 1600°—1800°C to achieve densification. The samples were held at the hot-pressing temperatures for several hours; therefore, this study also provided qualitative phase-stability information. The solubility limit of Al for Si in MoSi₂ was <5% at 1800°C. Samples that had 10% Al substituted for Si yielded approximately equal amounts of MoSi₂ and Mo(Al,Si)₂.     

Application of equilibrium thermodynamics to the development of diffusion barriers for copper metallization (invited)

The guidelines for designing a conductive, amorphous material, capable of thermodynamic equilibrium with copper, are defined using readily available thermodynamic information. The tradeoff between desired properties — equilibrium at the interfaces, amorphous microstructure, and electronic conductivity — are described, along with trends in relevant binary systems that result in these properties. These guidelines maximize the thermodynamic tendency for amorphous phase formation, in an attempt to minimize the need for nonequilibrium synthesis methods.     

Present Status of the SuperCDMS program

The expected final reach of the Weakly Interacting Massive Particle (WIMP) search experiment CDMS-II by the end of 2007 is a WIMP-nucleon cross-section sensitivity of 2.1×10⁻⁴⁴ cm². To proceed further in our search, we have proposed the SuperCDMS Phase A project that would deploy 42 1-inch thick Ge detectors, at a site deeper than the location of CDMS II, and reach a desired sensitivity goal of 1.3×10⁻⁴⁵ cm². These cross-sections are of interest and are complementary to Supersymmetry searches at the Large Hadron Collider (LHC) and future linear colliders. P.L. Brink for the SuperCDMS Collaboration.     

A fecal test for assessing phosphorus overfeeding on dairy farms: Evaluation using extensive farm data

Managing P on dairy farms requires the assessment and monitoring of P status of the animals so that potential overfeeding may be minimized. Numerous published studies have demonstrated that for lactating dairy cows, increasing P concentrations in diets led to greater P excretion in feces. More recent work reported that inorganic P (P_i) in 0.1% HCl extracts of feces (fecal extract P_i, g/kg) closely reflects dietary P changes. This has led to the proposal that 0.1% HCl fecal extract P_i may serve as an indicator of the animal's P status (adequate or excessive) when compared with a benchmark value. Here, we present the results of an extensive evaluation of the proposed fecal P indicator test. With samples (n = 575) from >90 farms, fecal total P (TP, g/kg) and fecal extract P were positively correlated with dietary P (X, g/kg): TP = 1.92X - 0.17 (R² = 0.36); fecal extract P = 1.82X - 2.54 (R² = 0.46). Fecal extract P was responsive to dietary P changes, whereas the remaining P, calculated as TP minus fecal extract P, was not. A provisional benchmark value of fecal extract P representing near-adequate P status was set at 4.75 g/kg. Assessment of the farm data using the benchmark indicated that 316 out of 575 data points were associated with possible P overfeeding. Advantages of the fecal-based test over feed-based analysis to assess P status are discussed. The fecal extract P method is a simple and practical test that can be used as an assessment tool for helping dairy producers improve P management and reduce their environmental footprint.     

An Algorithm for Generating Gamma Variates Based on the Weibull Distribution

An algorithm for generating gamma variates based on the Weibull distribution is given. This algorithm, a modification of one given by Phillips, is shown to be more accurate than the latter. The speed and memory requirements are similar.