553 research outputs found
A brief paper on improving active safety systems via HMI and dependability analysis
No full textAs new active safety systems are introduced in vehicles it is important to assure correct functionality also in the presence of faults. If faults are not considered in the design of such systems, the claimed safety benefits may be compromised. It is also important to take a holistic view in the design due to the close interaction between the driver and the control systems. There exist techniques for minimizing and tolerating faults in control systems and the design of interfaces for HMI (Human-Machine-Interaction) can be aided by models of human behaviour. This paper outlines on-going research on this close interaction between the driver and the vehicle with the aim of improving safety. The overall methods for attaining improved safety is to apply techniques for minimizing and tolerating faults in active safety systems based on recommendations from analysis of dependable systems and driver behaviour
Process-Oriented Collective Operations
No full textDistributing process-oriented programs across a cluster of machines requires careful attention to the effects of network latency. The MPI standard, widely used for cluster computation, defines a number of collective operations: efficient, reusable algorithms for performing operations among a group of machines in the cluster. In this paper, we describe our techniques for implementing MPI communication patterns in process-oriented languages, and how we have used them to implement collective operations in PyCSP and occam-pi on top of an asynchronous messaging framework. We show how to make use of collective operations in distributed processoriented applications. We also show how the process-oriented model can be used to increase concurrency in existing collective operation algorithms
Process for obtaining a fine-grained martensitic structure component
No full textThe disclosure relates to a process for the manufacture of a steel component comprising a fine-grained martensite structure component. The process comprises the steps of providing a steel component having an initial steel composition; introducing nitrogen into the steel component at a temperature T1 above 950°C, thereby creating an at least partly austenitic nitrogen-containing steel component; bringing the at least partly austenitic nitrogen-containing steel component to a temperature T2, such that austenite is decomposed into a steel component comprising at least an amount of carbon- and/or nitrogen-containing precipitates; bringing the steel component comprising at least an amount of carbon- and/or nitrogen-containing precipitates to a temperature T3 which is above T2, thereby creating an at least partly austenitic nitrogen-containing steel component optionally comprising at least an amount of carbon- and/or nitrogen-containing precipitates; and bringing the at least partly austenitic nitrogen-containing steel component to a temperature T4 that is below a martensite start temperature of the at least partly austenitic nitrogen-containing steel component for initiating transformation of at least some of the austenite into fine-grained martensite, thereby producing a steel component comprising a fine-grained martensite structure component
Optical characterisation of long wavelength self-assembled quantum dot lasers
No full textA detailed optical characterisation of (1.3 )InAs quantum-dot-in-well (DWELL) laser structures, is described
Substituent effects on aromatic stacking interactions
No full textSynthetic supramolecular zipper complexes have been used to quantify substituent effects on the free energies of aromatic stacking interactions. The conformational properties of the complexes have been characterised using NMR spectroscopy in CDCl3, and by comparison with the solid state structures of model compounds. The structural similarity of the complexes makes it possible to apply the double mutant cycle method to evaluate the magnitudes of 24 different aromatic stacking interactions. The major trends in the interaction energy can be rationalised using a simple model based on electrostatic interactions between the π-faces of the two aromatic rings. However, electrostatic interactions between the substituents of one ring and the π-face of the other make an additional contribution, due to the slight offset in the stacking geometry. This property makes aromatic stacking interactions particularly sensitive to changes in orientation as well as the nature and location of substituents
Chimpanzee faces under the magnifying glass: emerging methods reveal cross-species similarities and individuality
No full textIndependently, we created descriptive systems to characterize chimpanzee facial behavior, responding to a common need to have an objective, standardized coding system to ask questions about primate facial behaviors. Even with slightly different systems, we arrive at similar outcomes, with convergent conclusions about chimpanzee facial mobility. This convergence is a validation of the importance of the approach, and provides support for the future use of a facial action coding system for chimpanzees,ChimpFACS. Chimpanzees share many facial behaviors with those of humans. Therefore, processes and mechanisms that explain individual differences in facial activity can be compared with the use of a standardized systems such asChimpFACSandFACS. In this chapter we describe our independent methodological approaches, comparing how we arrived at our facial coding categories. We present some Action Descriptors (ADs) from Gaspar’s initial studies, especially focusing on an ethogram of chimpanzee and bonobo facial behavior, based on studies conducted between 1997 and 2004 at three chimpanzee colonies (The Detroit Zoo; Cleveland Metroparks Zoo; and Burger’s Zoo) and two bonobo colonies (The Columbus Zoo and Aquarium; The Milwaukee County Zoo). We discuss the potential significance of arising issues, the minor qualitative species differences that were found, and the larger quantitative differences in particular facial behaviors observed between species, e.g., bonobos expressed more movements containing particular action units (Brow Lowerer, Lip Raiser, Lip Corner Puller) compared with chimpanzees. The substantial interindividual variation in facial behavior within each species was most striking. Considering individual differences and the impact of development, we highlight the flexibility in facial activity of chimpanzees. We discuss the meaning of facial behaviors in nonhuman primates, addressing specifically individual attributes of Social Attraction, facial expressivity, and the connection of facial behavior to emotion. We do not rule out the communicative function of facial behavior, in which case an individual’s properties of facial behavior are seen as influencing his or her social life, but provide strong arguments in support of the role of facial behavior in the expression of internal states
Incentives, Technology and the Shift to Year-Round Dairying in Late 19th Century Denmark
No full textTheory of the electronic states of semiconductor heterostructures
No full textThis thesis is concerned with theoretical calculations of the properties of electronic bound states in semiconductor heterostructures. The complex band structure empirical pseudopotential method (EPM) is used as the foundation of the work. Spin orbit coupling and strain effects (due to lattice mismatch) are included in familiar ways, as is the transfer matrix method, allowing the study of arbitrarily configured heterostructures. These techniques are used to investigate the unusually deep InAs/AlSb conduction band well. The strong possibility of intraband transitions at electro magnetic wavelengths around 1.55µm is predicted, with corresponding enhanced momentum matrix elements and joint density of states over interband transitions. An InAs/GaSb/AlSb asymmetric well is investigated, paying particular attention to the bound states in the vicinity of the InAs/GaSb band overlap. The electron-like states are found to cross with heavy hole and anti-cross with light hole-like states, as a function of heterostructure dimension or applied electrostatic field. This is analogous to the hybridisation of states in the in-plane band structure, except that for zero in-plane wave vector there can be no appreciable hybridisation of electron and heavy hole states. A technique is described that has been developed to extract envelope functions from heterostructure wavefunctions calculated using the realistic complex band structure EPM approach. These envelope functions conform to Burt’s theory (M. G. Burt, J. Phys.: Condens. Matt. 4, 6651 (1992)) in that they are uniquely defined, continuous and smooth over all space. Comparisons with traditional effective mass envelope functions are made. The extracted envelope functions are used to demonstrate conclusively Burt's predictions (M. G. Burt, Superlatt. Mi- crostruct. 17, 335 (1995)) concerning the inadequacy of certain approximations for the calculation of interband dipole matrix elements and charge oscillation. Finally, the issue of k • p operator ordering is convincingly settled, in favour of 'ordered' over 'symmetrised' Hamiltonians, by comparison to EPM calculations, and using EPM derived k • p parameters
Developmental and handedness effects on tapping and drawing performance in 3-to-6 year olds.
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