A toy or a friend? Children's anthropomorphic beliefs about robots and how these relate to second-language word learning

This study investigates the degree to which children anthropomorphize a robot tutor and whether this anthropomorphism relates to their vocabulary learning in a second-language (L2) tutoring intervention. With this aim, an anthropomorphism questionnaire was administered to 5-year-old children (N = 104) twice: prior to and following a seven-session L2 vocabulary training with a humanoid robot. On average, children tended to anthropomorphize the robot prior to and after the lessons to a similar degree, but many children changed their attributed anthropomorphic features. Boys anthropomorphized the robot less after the lessons than girls. Moreover, there was a weak but significant positive correlation between anthropomorphism as measured before the lessons and scores on a word-knowledge post-test administered the day after the last lesson. There was also a weak but significant positive correlation between the change in anthropomorphism over time and scores on a word-knowledge post-test administered approximately 2 weeks after the last lesson. Our results underscore the need to manage children's expectations in robot-assisted education. Also, future research could explore adaptations to individual children's expectations in child-robot interactions.     

Nonlinear H2 and H∞ optimal controllersfor current-fed induction motors

This paper presents a nonlinear control design for both the H₂ and H_∞ optimal control for current-fed induction motor drives. These controllers are derived using analytical stationary solutions that minimize a generalized convex energy cost function including the stored magnetic energy and the coil losses, while satisfying torque regulation control objectives. Explicit control expressions for both the H₂ and H_∞ optimal design are given. Furthermore, the optimal attenuation factor, i.e., the optimal H_∞ norm and the corresponding worst case disturbance, are both computed explicitly     

Characterisation of unsealed anodic oxide layers on aluminium

The inhibiting effect of unsealed anodic oxide layers on filiform corrosion (FFC) was studied. This was done by means of impedance measurements, polarisation measurements and accelerated corrosion tests (Lockheed test). The electrochemical measurements indicate that both the porous layer and the barrier layer contribute to an enhanced corrosion resistance. In the Lockheed test, the specimens with a porous layer, did not show FFC. The specimens with a barrier layer revealed first a decrease of the number of filaments but after a certain point it increased. In contrast to this, the corroded area of the filaments showed a gradual decrease with increasing barrier layer thickness.     

Anodising as pretreatment of durable aluminium: The behaviour of several aluminium alloys to filiform corrosion

Aluminium alloys AA 3005, AA 3103 and AA 6063 were anodised in sulphuric acid under different conditions whereby a set of porous layers with varying thicknesses was produced. The influence of porous layer thickness on the filiform corrosion behaviour was examined by means of the Lockheed test. The filiform corrosion behaviour as a function of time was investigated. It appeared that the alloys showed similar filiform corrosion behaviour since for all alloys filiform corrosion was reduced considerably by increasing the porous layer thickness. The number of filaments N and the average filiform corroded surface R increase in time until a saturation level has been reached. However, the saturation level appeared to be different for each combination of alloy and porous layer thickness. The results indicate that the mechanism for filiform corrosion is the same for all three aluminium alloys.     

Time-dependent rheological behaviour of cemented backfill mixture

When cemented backfill mixture (CBM) is transported through pipelines from a backfill plant to stopes, it experiences shearing forces over the transport time. In this paper, the effects of solids concentration, binder content, shear rate and curing time on the time-dependent rheological behaviour of CBM were studied. It was found that over long periods of shearing at a constant rate greater than 5 s^?1, the shear stress decreased at first and then increased gradually with time. When the shear rate was less than 0.5 s^?1, shear stress increased slightly firstly with shearing time, then it started to behave similar to the test with a higher shear rate whose shear stress decreased firstly and then increased. The samples that were sheared at a higher shear rate exhibited a lower apparent viscosity and the higher yield stress CBM samples displayed more pronounced shear-thinning properties. It was also found that for transient flow, increasing the solids concentration and the curing time lead to both a higher initial shear stress (τ₀) and minimum shear stress (τ_min). When the cement to tailings ratio increased, the τ₀, τ_min and final shear stress after shearing for 3600 s (τ₃₆₀₀) increased at first, and then subsequently decreased. Moreover, changes in the solids concentration profile and the cement hydration property were displayed during the rheological tests.     

Experimental study on the mechanical properties and consolidation mechanism of microbial grouted backfill

Backfill mining technology is the practice of returning waste materials underground for both disposal and geotechnical stability, however, a challenge with current technologies is that they commonly require cement-based binders which have a relatively high environmental impact. Finding alternatives to cement-based binders can improve environmental performance and this paper proposes microbial grouted backfill (MGB) as a potential solution. In this paper, the effects of the cementation solution concentration (CSC), volume ratio of bacterial solution to cementation solution (VRBC), particle sizes of the aggregates, and the number of grouting batches on the mechanical properties of MGB are studied. The experimental results show that MGB strength increased, up to a peak value, as CSC was increased, before decreasing as CSC was increased further. The results also show that MGB strength increased, up to a peak value, as VRBC decreased, before decreasing as the VRBC was decreased further. The peak strength was achieved at a CSC of 2 mol/L and a VRBC of 1:9. The strength of the MGB also increased as the number of grouting batches increased. Graded MGB samples showed the highest UCS, 25.12 MPa, at particle sizes of 0.2 to 0.8 mm, while full (non-graded) MGB samples displayed mean UCS values ranging from 1.56 MPa when the maximum particle size was 0.2 mm, up to 13 MPa when the maximum particle size was 1.2 mm. MGB samples are consolidated by the calcium carbonate that is precipitated during microbial metabolism, and the strength of MGB increases linearly as calcium carbonate content increases. The calcium carbonate minerals produced in MGB materials are primarily calcite, with secondary amounts of vaterite.     

Charles R. (Bob) Schuster (1930–2011).

Charles R. (Bob) Schuster, an internationally recognized researcher on the psychopharmacology of drugs of abuse, passed away on February 21, 2011. Bob Schuster was a pioneer in the scientific study of addiction and one of the founders of a specialized research field called behavioral pharmacology. Bob mentored many young scientists, including 15 doctoral students, 9 postdoctoral fellows, and many visiting scientists from around the world, as well as junior faculty members at the academic institutions where he had faculty appointments. Bob was active in numerous professional organizations and was the recipient of many national and international awards. Personally, Bob Schuster touched the lives of a great many people: his students, colleagues, extended family, and many friends. Bob is survived by his wife and colleague Chris-Ellyn Johanson; four children, Lyzbett, Rebecca, Robert, and Alyson; and seven grandchildren. He is also survived by his sister Bette Quemore. He was a man of many talents, a loving husband and father, and a great friend. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Role of unconditioned and conditioned drug effects in the self-administration of opiates and stimulants.

Reviews recent behavioral and neuropharmacological findings, which suggest that opiate and stimulant drugs act on common neurochemical systems of the brain to generate positive appetitive states that maintain drug-taking behavior. CSs associated with these drugs arouse neural states that mimic features of those produced by the drugs themselves and thereby serve to increase the effectiveness of drug-related stimuli and to increase the probability of drug-related thoughts and actions. This positive incentive account of compulsive drug use contrasts with the drive-reduction view that continued drug use depends primarily on efforts to reduce or to avoid symptoms of withdrawal, and that conditioned stimuli initiate and maintain drug-taking behavior through the elicitation of withdrawal-like, drug-opposing CRs. (4 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification and characterization of human B-cell epitopes in recombinant antigens of Leishmania aethiopica

Recombinant DNA fragments from Leishmania aethiopica that code for epitopes which react with human antibodies have been characterized by cross-hybridization studies and DNA sequence analysis. Twenty clones could be grouped into seven different groups (I-VII), probably representing seven different L. aethiopica antigens. The DNA sequences of representative clones from the seven groups have been obtained and the amino acid sequence of the respective recombinant antigens established. The recombinant antigens have been analysed by epitope scanning with patient sera, and octapeptides that contain potential B-cell epitopes have been identified in all seven recombinant antigens. These octapeptides have further been tested with additional patient sera and control sera, and three octapeptides (HAFCHEEG, YHSSVVHD and SYAPCSLK) were found to contain major epitopes recognizing specific antibodies in nine, seven and four, respectively, of the twenty sera tested. Fifteen of the twenty sera reacted with one or more of these three octapeptides.     

Coherence-tuned interrogation of a remote elliptical-core,dual-mode fiber strain sensor

Two dual-mode fibers in tandem act as unbalanced sensor and recovery interferometers. We investigate how coherence-tuned interrogation of the remote sensor fiber is affected by the coherence properties of the multimode laser diode source and the modal group index difference of the dual-mode fibers. The parameters for optimized sensor performance are ascertained. We focus particularly on the recovery of small optical phase modulations induced by periodic strain. Using homodyne phase tracking, stability of the detected ac signal is achieved to within ±10^-3 in the presence of additional, quasistatic phase drifts of large amplitude. The minimum detectable differential modal phase modulation is 5 μrad rms/√Hz at 70 Hz. As an example, remote interrogation of a piezoelectric quartz high-voltage transducer is demonstrated