Computational methods for fracture analysis of heavy-section steel technology (HSST) pressure vessel experiments

This paper summarizes the capabilities and applications of the general-purpose and special-purpose computer programs that have been developed at the Oak Ridge National Laboratory (ORNL) for use in fracture mechanics analyses of HSST pressure vessel experiments. Emphasis is placed on the OCA/USA code, which is designed for analysis of pressurized-thermal-shock (PTS) conditions, and on the ORMGEN/ADINA/ORVIRT system which is used for more general analysis. Fundamental features of these programs are discussed, along with applications to pressure vessel experiments.     

A comparison of self-reported drug use with a urine drug screen in a working population.

This study summarized information on 162 workers who completed urine screen and self-report concerning drug use. It is the first to compare self-report of drug use in the workplace with a urine screen in which individual participant (nonaggregate) data were used. The findings indicate that agreement between the 2 methods of drug detection, although statistically significant, is at best only moderate. The level of agreement was consistent for segments of the sample when divided by sociodemographic characteristics. Although urine screen may be the more reliable and accurate method of detecting prevalence of drug use, self-report must be considered to assess drug use histories and the role of other variables. These 2 methods should be considered as complementary assessment techniques; the appropriate method depends on the conditions and purposes of the drug use study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recruiting sources: Another look.

Examined relations between recruiting source, employee tenure, and productivity for 618 male technical salespersons over a 2-yr period. All data were obtained from personnel records. Unlike earlier research, a relation between recruitment source and job tenure was not found, nor was recruiting source found to be related to employee productivity. Explanations for differences between the present findings and earlier research include characteristics of this particular job, the fact that multiple jobs and levels were not always considered, and the turnover rate of the sample job. Additional findings support D. P. Schwab's (1982) suggestion that recruiting sources may be differentially effective to the extent that they reach different populations. A comparison of research results with textbook presentations and practitioner articles is also provided, with a discussion of the gap between research and practice. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does the transactional–transformational leadership paradigm transcend organizational and national boundaries?

There is universality in the transactional–transformational leadership paradigm. That is, the same conception of phenomena and relationships can be observed in a wide range of organizations and cultures. Exceptions can be understood as a consequence of unusual attributes of the organizations or cultures. Three corollaries are discussed. Supportive evidence has been gathered in studies conducted in organizations in business, education, the military, the government, and the independent sector. Likewise, supportive evidence has been accumulated from all but 1 continent to document the applicability of the paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Three-dimensional finite deformation, rolling contact of a hyperelastic cylinder: Formulation of the problem and computational results

In this paper, a general class of three-dimensional rolling contact problems is analyzed by finite element methods. Finite deformations and frictional contact are considered. The results of several numerical experiments are also presented.     

A software toolkit for hierarchical task analysis

This paper describes a prototype software tool that offers support to the human factors specialist using hierarchical task analysis (HTA). The tool provides a direct manipulation diagram editor for HTA and provides high-quality output of analyses, in both graphic and automatically generated tabular form. The tool is implemented in Smalltalk-80 and currently runs on Macintosh computers.     

Structural Relaxations in Alkali Silicate Systems by Brillouin Light Scattering

The Brillouin light scattering technique was used to investigate the viscoelastic relaxations in alkali silicate systems up to temperatures of 1500°C. The line shape analysis of the Brillouin spectra reveals information about the mechanical rigidity and the viscous dissipation in the scattering medium. Brillouin frequency shifts and the frequency-dependent viscosity coefficients, v ' were measured as a function of temperature. The shapes of the v ' vs temperature curves, and the location of their maxima on the temperature scale, reveal the activation energies and the resonance frequencies of the underlying mechanisms. In binary alkali silicates, small dissipation maxima were observed between the glass transition and the melting temperature, which are attributed to the increased cation mobility as a result of the accelerated disintegration of the silica networks. In mixed alkali systems, multiple dissipation maxima are observed. These are spread over a range of temperatures, which are distinctly higher than in binary systems.     

Remote sensing of the atmosphere and the small angle approximation to the solution of the radiative transfer equation

Modern methods of remote sensing of the atmosphere and the surface are based on minimizing the difference between simulated and measured reflectances. An iterative process to specify the model of the atmosphere is used, and the direct problems to the radiative transfer equation (RTE) are solved on each iteration loop. These direct problems have to be solved quickly for realistic models of the atmosphere under peaked-forward scattering by aerosol particles, water droplets, and ice crystals. Accurate and fast algorithms to solve the RTE under these conditions are in great demand. A method based upon the new version of small angle approximation to the singular component of the solution is presented. Numerical results in the problem on reflection of the visible light by aerosol and cloud layers are presented. Calculation time reduction due to the small angular technique is shown.     

Effect of visual marbling on sensory properties and quality traits of pork loin

Pork loins (N = 53) were selected from a commercial packing plant to determine the influence of subjective marbling score on sensory attributes and eating quality properties. The pork loins were obtained from commercially raised hybrid barrows (average carcass weight = 67.7 kg), originating from nine cooperating herds, and fed similar diets throughout the finishing period. Carcass quality measurements, trained sensory panel analyses, fatty acid composition, thiobarbituric acid-reactive substance (TBARS) index, and cholesterol content were assessed and analyzed on the individual pork loins. With an increase in marbling level, there was a corresponding decrease in drip loss (P = 0.049) and observed increases in pH (P = 0.001), sensory tenderness (P = 0.001), and sensory juiciness scores (P = 0.017). The most notable results demonstrated that protein concentrations were reduced as marbling levels amplified (P = 0.012). The increase in marbling score was observed to be a significant source of variation in polyunsaturated fatty acid (PUFA) concentrations. Linoleic and arachidonic acids decreased in both raw and cooked samples as marbling score increased. The data demonstrated that visual marbling score does have an influence on sensory properties and pork quality.     

Working the Martian night shift - the MER surface operations process

The Mars exploration rover mission has conducted continuous Mars surface operations for over 24 months to date. The operations processes and tools put in place before landing have continued to develop throughout the surface mission, evolving from a capability intended to operate for less than four months to one capable of continuing indefinitely. The MER operations design has been accepted as baseline for the Mars Science Laboratory mission, scheduled for launch in 2009. Our experiences during MER's exciting and unexpectedly extensive surface exploration phase may provide useful insights for other future long duration surface missions.