10,344 research outputs found
Fishes of the Strawberry River System of Northcentral Arkansas
A survey of the fishes of the Strawberry River in northcentral Arkansas was made between August 1967 and November 1973. Field collections, literature records and museum specimens showed the ichthyofauna of the Strawberry River to be made up of 95 species distributed among 17 families. Two erroneous records are deleted. One subspecies, Etheostoma spectabile fragi,, is endemic to the river. Records of Notropis fumeus, Etheostotna nigrum, Etheostoma proeliare and Percina sciera represent extensions of previously known ranges within the state
Experiences with the JPL telerobot testbed: Issues and insights
The Jet Propulsion Laboratory's (JPL) Telerobot Testbed is an integrated robotic testbed used to develop, implement, and evaluate the performance of advanced concepts in autonomous, tele-autonomous, and tele-operated control of robotic manipulators. Using the Telerobot Testbed, researchers demonstrated several of the capabilities and technological advances in the control and integration of robotic systems which have been under development at JPL for several years. In particular, the Telerobot Testbed was recently employed to perform a near completely automated, end-to-end, satellite grapple and repair sequence. The task of integrating existing as well as new concepts in robot control into the Telerobot Testbed has been a very difficult and timely one. Now that researchers have completed the first major milestone (i.e., the end-to-end demonstration) it is important to reflect back upon experiences and to collect the knowledge that has been gained so that improvements can be made to the existing system. It is also believed that the experiences are of value to the others in the robotics community. Therefore, the primary objective here will be to use the Telerobot Testbed as a case study to identify real problems and technological gaps which exist in the areas of robotics and in particular systems integration. Such problems have surely hindered the development of what could be reasonably called an intelligent robot. In addition to identifying such problems, researchers briefly discuss what approaches have been taken to resolve them or, in several cases, to circumvent them until better approaches can be developed
The formation of glycocyamine in man and its urinary excretion
Glycocyamine was first isolated from human and dog urine and identified by Weber (1-3). He supported the view that glycocyamine is a normal precursor of creatine and that its appearance in urine (2) is “an overflow phenomenon of an intermediate metabolic product ...” He expressed no views on the mechanism of its formation
Recommended from our members
The roles of computer self-efficacy, outcome expectancy, and attribution theory in impacting computer system use
TJte process by which individuals accept or reject information technologies was theoretically explained in a model employing attributional relationships and computer self-ejficacy and outcome expectancy. The model was empirically tested using structural equations modeling and data collected in afield setting. The results provided partial confiirmation of the theory that attributions to ability, effort, luck, and task difficulty impact information system use mediated by computer self-ejficacy and outcome expectancy. The stable attributions of ability and task difficulty had meaningful impacts on computer self-ejficacy. Similarly, task difficulty had a meaningful impact on outcome expectancy. The unstable attributes of effort and luck demonstrated meaningful impacts on computer self-ejficacy but not outcome expectancy. In addition, these results showed that computer self-ejficacy had a significant impact on both outcome expectancy and computer system use
Recommended from our members
The effects of computer self-efficacy and outcome expectancy on end-user job control and stress
This article examines the effects of computer self-efficacy and outcome expectancy on the end-user\u27s sense of felt stress as mediated by job control. A nationwide survey of information technology end-users provided the sample. The results show that computer self-efficacy directly impacts personal and job related outcome expectancies and that computer self-efficacy and job related outcome expectancies directly affect job control. Job control is shown to mediate the impacts of computer self-efficacy and job related expectancies on stress. The results are discussed and implications for information technology managers are presented
The Impacts of End-User Gender, Education, Performance, and System Use on Computer Self-Efficacy and Outcome Expectancy
John W. Henry, Ph.D., is an associate professor of management, Department of Management, College of Business, Georgia Southern University, Statesboro, Ga.
Robert W. Stone, Ph.D., is an associate professor of information systems, Department of Business, College of Business and Economics, University of Idaho, Moscow, ID
Mach number effects on transonic aeroelastic forces and flutter characteristics
Transonic aeroelastic stability analysis and flutter calculations are presented for a generic transport-type wing based on the use of the CAP-TSD (Computational Aeroelasticity Program - Transonic Small Disturbance) finite-difference code. The CAP-TSD code was recently developed for transonic unsteady aerodynamic and aeroelastic analysis of complete aircraft configurations. A binary aeroelastic system consisting of simple bending and torsion modes was used to study aeroelastic behavior at transonic speeds. Generalized aerodynamic forces are presented for a wide range of Mach number and reduced frequency. Aeroelastic characteristics are presented for variations in freestream Mach number, mass ratio, and bending-torsion frequency ratio. Flutter boundaries are presented which have two transonic dips in flutter speed. The first dip is the usual transonic dip involving a bending-dominated flutter mode. The second dip is characterized by a single degree-of-freedom torsion oscillation. These aeroelastic results are physically interpreted and shown to be related to the steady state shock location and changes in generalized aerodynamic forces due to freestream Mach number
The application of low crude protein wheat-soyabean diets to growing and finishing pigs: 2. The effects on nutrient digestibility, nitrogen excretion, faecal volatile fatty acid concentration and ammonia emission from boars
peer-reviewedThis study received financial support from Telltech Ltd. (Wicklow, Ireland) and Enterprise Ireland (Dublin, Ireland).Diets containing 132, 152, 183 and 206 g/kg crude protein (CP) were fed to growing and
finishing boars to evaluate the effect on nutrient digestibility, N balance, faecal volatile
fatty acids (VFA) and ammonia-N (NH3–N) emission. Dietary CP concentration was
adjusted by altering the ratio of wheat:soyabean meal. Lysine, threonine, tryptophan
and total sulphur-containing amino acids were included in all diets at concentrations
equivalent to that in the highest CP diet. All diets were formulated to provide 9.7 MJ/kg
of net energy. Urine and faeces were collected from 16 boars (4 boars per treatment)
housed in metabolism crates. Collections were performed at 72, 80 and 87 kg live weight.
NH3–N emission was measured over 10 days using a laboratory scale procedure.
Reducing the concentration of dietary CP decreased N intake (linear, P < 0.01), the
excretion of urinary N, ammoniacal N and total N (linear, P < 0.001; cubic, P < 0.001)
and the emission of NH3–N (linear, P < 0.001; cubic, P < 0.01). Total N excretion and
NH3–N emission decreased 8.7% and 10.1% per 10 g/kg reduction in dietary CP
concentration between 205.6 and 131.9 g/kg, respectively. There was no interaction
between dietary CP concentration and collection period. N balance differed between the collection periods and less NH3–N was emitted at 87 kg than at 72 kg. Decreasing
dietary CP reduced faecal VFA concentration (linear, P < 0.05) and the molar proportions
of acetic and butyric acids (quadratic, P < 0.01).Enterprise Irelan
- …