Brain signal-based safety measure activation for robotic systems

In this paper, we present our approach for using EEG signals to activate safety measures of a robot when an error or unexpected event is perceived by the human operator. In particular, we consider brain-based error perception while the operator passively observes the robot performing an action. Our approach consists of monitoring EEG signals and detecting a brain potential called error related negativity (ERN) that spontaneously occurs when the operator perceives an error made by the robot or when an unexpected event occurs. We detect ERN by pre-training two linear classifiers using data collected from a preliminary experiment based on a visual reaction task. We derive the probability of failure in demand (PFD), commonly used to assess functional safety for a two-channel verification system based on the combination of linear classifiers. Functional safety analysis was then performed on a BMI-based robotic framework in which a signal was sent to the robot to active its safety measures in when an ERN was detected. Using brain-based signals, we demonstrate that it is possible to send an emergency stop action during mobile navigation task when unexpected events occur with an accuracy of 75%.     

PHoM – a Polyhedral Homotopy Continuation Method for Polynomial Systems

PHoM is a software package in C++ for finding all isolated solutions of polynomial systems using a polyhedral homotopy continuation method. Among three modules constituting the package, the first module StartSystem constructs a family of polyhedral-linear homotopy functions, based on the polyhedral homotopy theory, from input data for a given system of polynomial equations f(x)=0. The second module CMPSc traces the solution curves of the homotopy equations to compute all isolated solutions of f(x)=0. The third module Verify checks whether all isolated solutions of f(x)=0 have been approximated correctly. We describe numerical methods used in each module and the usage of the package. Numerical results to demonstrate the performance of PHoM include some large polynomial systems that have not been solved previously.AMS Subject Classification: Primary: 65H10 system of equations, secondary: 65H20 global methods, including homotopy approaches.     

Home environment and development of slow-learning adolescents: Reciprocal relations.

Investigated the reciprocal relation between the home environment and the development of 148 7–14 yr old slow-learners longitudinally over a 3-yr period. Annual assessments of the home environment included childrearing attitudes, educationally relevant stimuli and opportunities, and psychosocial climate and environmental press of the home. Main caregivers (usually mothers) were administered the Henderson Environmental Learning Process Scale and the Family Environment Scale. Measures of the Ss' development included social competency, psychosocial adjustment, and self-concept. Partial correlation and hierarchical multiple regression analysis revealed significant influence of environmental stimulation, both cognitive and social, on the Ss' subsequent cognitive development and social adjustment. Harmony and quality of parenting, and educational expectation and aspiration were the 2 most salient environmental variables associated with the Ss' development. The study also demonstrated significant influence of the Ss' psychosocial adjustment on subsequent changes in the home environment including psychosocial climate of the home, family adjustment, and the parents' educational expectations and aspirations. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Proposal for a new magnet lattice for an electron storage ring for a high brightness synchrotron radiation source

A new magnet lattice, named “variable emittance”, for an electron storage ring dedicated to synchrotron radiation is proposed. The lattice has a high flexibility to meet the requirements for a high performance undulator as well as for conventional synchrotron radiation from a bending magnet. Tune shifts due to magnet imperfections were simulated and it is found that the periodic solution of the optics is stable enough except for a very high tune region. The effects of undulators and wigglers on the stored beam were studied and a correction for the tune shift is found necessary for high field wigglers.     

Are Monkeys Aesthetists? Rensch (1957) Revisited.

Three experiments assessed whether capuchin monkeys (Cebus apella) and squirrel monkeys (Saimiri sciureus) prefer regular and symmetrical visual patterns. Pictorial representations of faces were included in 1 stimulus set. When the monkeys could pick up and manipulate small cards bearing the stimuli, all preferences expressed by capuchins and most of those expressed by squirrel monkeys were for regular stimuli. Symmetry of the patterns was influential but not essential. Some preferences were also found for faces. When images of the patterns were presented on a touch screen, capuchins continued to express preferences especially for regular and symmetrical stimuli, but they showed some avoidance of faces. Squirrel monkeys responded less discriminatingly to the touch screen stimuli. The findings provide support for B. Rensch's (1957) claim that monkeys prefer visual stimuli that humans find aesthetically pleasing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

What perceptual rules do Capuchin Monkeys (Cebus Apella) follow in completing partly occluded figures?

Capuchin monkeys (Cebus apella) matched a variety of rodlike figures, distinguishable only by their central portions. The monkeys were then tested for perceptual completion rules by examining which comparison figures they would choose as matching the sample with the critical central portion occluded by a horizontal belt. In Experiment 1, the monkeys overwhelmingly chose a straight rod over disconnected rods and rods having irregular shapes at their center, irrespective of the presence-absence of common motion of visible parts of the samples. The monkeys chose a connected rod for relatable rods and disconnected rods for nonrelatable ones in Experiment 2. In Experiments 3 and 4, some of the monkeys chose rods specified by the global regularity of the contour, whereas others did not. Experiment 5 showed that humans and capuchin monkeys basically follow similar perceptual rules in completing occluded contours, but the global regularity rule may be stronger in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Peeling Behavior and Spalling Resistance of Bonded Bidirectional Fiber Reinforced Polymer Sheets

This paper presents the peeling behavior and spalling resistant effect of bidirectional fiber reinforced polymer (FRP) sheets externally bonded to concrete surfaces. Experimental investigations are carried out through a series of newly designed punching-peeling tests. A wide range of variables, such as FRP sheet layers and fiber direction, plate constraint, concrete strength, adhesives, bond length of FRP sheets, diameter of indenter, and types of fibers, are considered in the experimental investigation. Theoretical study is also conducted for the specimens. Interfacial fracture energy is calculated analytically using a membrane-peeling method. It is realized that only two material parameters, i.e., the interfacial fracture energy of the FRP-concrete interface and the tensile stiffness of FRP sheets, are necessary to represent the interfacial spalling resistant behavior. Finally, the theoretical results are validated by comparing with experimental results. Comparison of theoretical to experimental results shows that the proposed theoretical model is satisfactory in reasonably and accurately predicting the peeling behavior and spalling resistant capacity of bidirectional FRP sheets bonded to concrete surface.     

Natural choice in nonhuman primates.

In 5 experiments, 4 monkeys and 1 ape chose between 2 food sources, each held in 1 of the experimenter's hands while he stood in front of a cage. When choosing between 2 sources of the same food that differed in amount, preference for the larger amount decreased as the size of each good proportionately increased. A second finding was that subjects were indifferent between a 2-food mixture and a single food that was part of the mixture if the single food was the preferred food of the mixture, a result suggesting the less preferred food had no value. Experiment 6 replicated these effects in 4 additional monkeys. These effects may be incompatible with previous theorizing about animal choice and may reflect a cognitive difference between nonhuman primates and humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Figure/ground segregation from temporal delay is best at high spatial frequencies

Two experiments investigated the role of spatial frequency in performance of a figure/ground segregation task based on temporal cues. Figure orientation was much easier to judge when figure and ground portions of the target were defined exclusively by random texture composed entirely of high spatial frequencies. When target components were defined by low spatial frequencies only, the task was nearly impossible except with long temporal delay between figure and ground. These results are inconsistent with the hypothesis that M-cell activity is primarily responsible for figure/ground segregation from temporal delay. Instead, these results point to a distinction between temporal integration and temporal differentiation. Additionally, the present results can be related to recent work on the binding of spatial features over time.     

Maternal identification from skeletal remains of an infant kept by the alleged mother for 16 years with DNA typing

This is a case study concerning maternal identification by DNA typing at various loci. An infant skeleton was found in the alleged mother's apartment after it was kept for 16 years. We obtained the skeletal remains as well as saliva stains from the alleged mother. DNA typing was conducted for three loci in the HLA class II region (HLA-DQA1, -DPB1, and DRB1), five loci with the AmpliType PM kit (LDLR, GYPA, HBGG, D7S8, and GC), five STR loci (LPL, vWA, F13B, TH01, and TPOX) and D-loop region in mtDNA for maternal identification. Sex determination was accomplished using fluorescent DNA capillary electrophoresis typing. Approximately 5 ng of human DNA was recovered from 1 g of femur bone retrieved from the infant skeletal remains. The probability of two unrelated Japanese sharing the same genotypes was estimated as 7.2 x 10(-11). The combined probability of exclusion that an individual is not the mother was also calculated at 0.998. We therefore conclude that the skeleton is from a female infant, and that there is no inconsistency in the claim that the infant was a daughter of the alleged mother.