Emergent task-specific object semantics through distributed experience networks

Autonomous development of sensorimotor coordination enables a robot to adapt and change its action choices to interact with the world throughout its lifetime. The Experience Network is a structure that rapidly learns coordination between visual and haptic inputs and motor action. This paper presents methods which handle the high dimensionality of the network state-space which occurs due to the simultaneous detection of multiple sensory features. The methods provide no significant increase in the complexity of the underlying representations and also allow emergent, task-specific, semantic information to inform action selection. Experimental results show rapid learning in a real robot, beginning with no sensorimotor mappings, to a mobile robot capable of wall avoidance and target acquisition.

Ocular characteristics in myopic anisometropia

PURPOSE: To investigate the interocular symmetry of ocular optical, biometric and biomechanical characteristics between the more and less ametropic eyes of myopic anisometropes. METHODS: Thirty-four young, healthy myopic anisometropic adults (≥ 1 D spherical equivalent difference between eyes) without amblyopia or strabismus were recruited. A range of biometric and optical parameters were measured in the more and less ametropic eye of each subject including; axial length, ocular aberrations, intraocular pressure and corneal topography, thickness and biomechanics. Morphology of the anterior eye in primary and downward gaze was examined using custom software analysis of high resolution digital images. Ocular sighting dominance was assessed using the hole-in-the-card test. RESULTS: Mean absolute spherical equivalent anisometropia was 1.74 ± 0.74 D. There was a strong correlation between the degree of anisometropia and the interocular difference in axial length (r = 0.81, p < 0.001). The more and less ametropic fellow eyes displayed a high degree of interocular symmetry for the majority of biometric, biomechanical and optical parameters measured. When the level of anisometropia exceeded 1.75 D (n = 10), the more myopic eye was the dominant sighting eye in nine of these ten subjects. Subjects with greater levels of anisometropia (> 1.75 D) also showed high levels of correlation between the dominant and non-dominant eyes in their biometric, biomechanical and optical characteristics. CONCLUSIONS: Although significantly different in axial length, anisometropic eyes display a high degree of interocular symmetry for a range of anterior eye biometrics and optical parameters. For higher levels of anisometropia, the more myopic eye tends to be the dominant sighting eye.

Mechanism of interaction of hydrocalumites (Ca/Al-LDH) with methyl orange and acidic scarlet GR

The development of new materials for water purification is of universal importance. Among these types of materials are layered double hydroxides (LDHs). Non-ionic materials pose a significant problem as pollutants. The interaction of methyl orange (MO) and acidic scarlet GR (GR) adsorption on hydrocalumite (Ca/Al-LDH-Cl) were studied by X-ray diffraction (XRD), infrared spectroscopy (MIR), scanning electron microscope (SEM) and near-infrared spectroscopy (NIR). The XRD results revealed that the basal spacing of Ca/Al-LDH-MO was expanded to 2.45 nm, and the MO molecules were intercalated with a inter-penetrating bilayer model in the gallery of LDH, with 49o tilting angle. Yet Ca/Al-LDH-GR was kept the same d-value as Ca/Al-LDH-Cl. The NIR spectrum for Ca/Al-LDH-MO showed a prominent band around 5994 cm-1, assigned to the combination result of the N-H stretching vibrations, which was considered as a mark to assess MO- ion intercalation into Ca/Al-LDH-Cl interlayers. From SEM images, the particle morphology of Ca/Al-LDH-MO mainly changed to irregular platelets, with a “honey-comb” like structure. Yet the Ca/Al-LDH-GR maintained regular hexagons platelets, which was similar to that of Ca/Al-LDH-Cl. All results indicated that MO- ion was intercalated into Ca/Al-LDH-Cl interlayers, and acidic scarlet GR was only adsorped upon Ca/Al-LDH-Cl surfaces.

Choosing landmarks for risky planning

This work examines the effect of landmark placement on the efficiency and accuracy of risk-bounded searches over probabilistic costmaps for mobile robot path planning. In previous work, risk-bounded searches were shown to offer in excess of 70% efficiency increases over normal heuristic search methods. The technique relies on precomputing distance estimates to landmarks which are then used to produce probability distributions over exact heuristics for use in heuristic searches such as A* and D*. The location and number of these landmarks therefore influence greatly the efficiency of the search and the quality of the risk bounds. Here four new methods of selecting landmarks for risk based search are evaluated. Results are shown which demonstrate that landmark selection needs to take into account the centrality of the landmark, and that diminishing rewards are obtained from using large numbers of landmarks.

Raman spectroscopy of the multi-anion mineral schlossmacherite (H3O,Ca)Al3(AsO4,PO4,SO4)2(OH)6

The mineral schlossmacherite (H3O,Ca)Al3(AsO4,PO4,SO4)2(OH)6 , a multi-cation-multi-anion mineral of the beudantite mineral subgroup has been characterised by Raman spectroscopy. The mineral and related minerals functions as a heavy metal collector and is often amorphous or poorly crystalline, such that XRD identification is difficult. The Raman spectra are dominated by an intense band at 864 cm-1, assigned to the symmetric stretching mode of the AsO43- anion. Raman bands at 809 and 819 cm-1 are assigned to the antisymmetric stretching mode of AsO43- . The sulphate anion is characterised by bands at 1000 cm-1 (ν1), and at 1031, 1082 and 1139 cm-1 (ν3). Two sets of bands in the OH stretching region are observed: firstly between 2800 and 3000 cm-1 with bands observed at 2850, 2868, 2918 cm-1 and secondly between 3300 and 3600 with bands observed at 3363, 3382, 3410, 3449 and 3537 cm-1. These bands enabled the calculation of hydrogen bond distances and show a wide range of H-bond distances.

Performance recordivity : studio music in a live context

A broad range of positions is articulated in the academic literature around the relationship between recordings and live performance. Auslander (2008) argues that “live performance ceased long ago to be the primary experience of popular music, with the result that most live performances of popular music now seek to replicate the music on the recording”. Elliott (1995) suggests that “hit songs are often conceived and produced as unambiguous and meticulously recorded performances that their originators often duplicate exactly in live performances”. Wurtzler (1992) argues that “as socially and historically produced, the categories of the live and the recorded are defined in a mutually exclusive relationship, in that the notion of the live is premised on the absence of recording and the defining fact of the recorded is the absence of the live”. Yet many artists perform in ways that fundamentally challenge such positions. Whilst it is common practice for musicians across many musical genres to compose and construct their musical works in the studio such that the recording is, in Auslander’s words, the ‘original performance’, the live version is not simply an attempt to replicate the recorded version. Indeed in some cases, such replication is impossible. There are well known historical examples. Queen, for example, never performed the a cappella sections of Bohemian Rhapsody because it they were too complex to perform live. A 1966 recording of the Beach Boys studio creation Good Vibrations shows them struggling through the song prior to its release. This paper argues that as technology develops, the lines between the recording studio and live performance change and become more blurred. New models for performance emerge. In a 2010 live performance given by Grammy Award winning artist Imogen Heap in New York, the artist undertakes a live, improvised construction of a piece as a performative act. She invites the audience to choose the key for the track and proceeds to layer up the various parts in front of the audience as a live performance act. Her recording process is thus revealed on stage in real time and she performs a process that what would have once been confined to the recording studio. So how do artists bring studio production processes into the live context? What aspects of studio production are now performable and what consistent models can be identified amongst the various approaches now seen? This paper will present an overview of approaches to performative realisations of studio produced tracks and will illuminate some emerging relationships between recorded music and performance across a range of contexts.

A simulation to describe the effects of in-shoe orthoses

The subtalar joint has been presumed to account for most of the pathologic motion in the foot and ankle, but research has shown that motion at other foot joints is greater than traditionally expected. Although recent research demonstrates the complexity of the kinematic variables in the foot and ankle, it still fails to expand our knowledge of the role of the musculotendinous structures in the biomechanics of the foot and ankle and how this is affected by in-shoe orthoses. The aim of this study was to simulate the effect of in-shoe foot orthoses by manipulation of the ground reaction force (GRF) components and centre of pressure (CoP) to demonstrate the resultant effect on muscle force in selected muscles during both the rearfoot loading response and stance phase of the gait cycle. We found that any medial wedge increases ankle joint load during gait cycle, while a lateral wedge decreases the joint load during the stance phase.

Is the mineral borickyite (Ca,Mg)(Fe3+,Al)4(PO4,SO4,CO3)(OH)8•3-7.5H2O the same as delvauxite CaFe3+4(PO4,SO4)2(OH)8•4-6H2O?

The two minerals borickyite and delvauxite CaFe3+4(PO4,SO4)2(OH)8•4-6H2O have the same formula. Are the minerals identical or different? The minerals borickyite and delvauxite have been characterised by Raman spectroscopy. The minerals are related to the minerals diadochite and destinezite. Both minerals are amorphous. Delvauxite appears to vary in crystallinity from amorphous to semi-crystalline. The minerals are often X-ray non-diffracting. The minerals are found in soils and may be described as ‘colloidal’ minerals. Vibrational spectroscopy enables an assessment of the molecular structure of borickyite and delvauxite. Bands are assigned to phosphate and sulphate stretching and bending modes. Multiple water bending and stretching modes imply that non-equivalent water molecules in the structure exist with different hydrogen bond strengths. The two minerals show differing spectra and must be considered as different minerals.

Information technology resources,complementaries and capabilities : towards a deeper understanding of leveraging business value from IT

Organisations devote substantial resources to acquire information technology (IT), and explaining the important issue of how IT can affect performance has posed a significant challenge to information system (IS) researchers. Owing to the importance of expanding our understanding on how and where IT and IT-related resources impact organisational performance, this study investigates the differential effects of IT resources and IT-related capabilities, in the presence of platform-related complementarities, on business process performance. We test these relationships empirically via a field survey of 216 firms. The findings suggest that IT resources and IT-related capabilities explain variance in performance. Of interest is the finding that IT resources and IT-related capabilities ability to explain variance in business process is further enhanced by the presence of the platform-related complementarities. Our findings are largely consistent with the resource-based and complementarity arguments of sources of IT-related business value.

Porous Ca-Si-based nanospheres : a potential intra-canal disinfectant-carrier for infected canal treatment

The aim of this study is to develop a new intra-canal disinfectant-carrier for infected canal treatment. To achieve this purpose, a new porous Ca-Si (CS)-based nanosphere was synthesized and characterized. Results showed that the nanospheres can infiltrate into dentinal tubules and released the ampicillin over one week time in a sustained manner. The release of ampicillin from spheres has significantly antibacterial property. Extensive and well-organized in vitro mineralization and crystallization of apatite were induced on the surface of dentin slices covered by CS nanospheres. All these features indicate that the porous CS nanospheres may be developed into a new intra-canal disinfectant-carrier for infected canal treatment.

Vibrational spectroscopic study of the minerals cavansite and pentagonite Ca(V4+O)Si4O10.4H2O

The bright blue minerals cavansite and pentagonite, a calcium vanadium silicate Ca(V4+O)Si4O10.4H2O, have been studied by UV–Visible, Raman and infrared spectroscopy. Cavansite shows an open porous structure with very small micron sized holes. Strong UV–Visible absorption bands are observed at around 403, 614 and 789 nm for cavansite and pentagonite. The Raman spectrum of cavansite is dominated by an intense band at 981 cm -1 and pentagonite by a band at 971 cm-1 attributed to the stretching vibrations of (SiO3)n units. Cavansite is characterised by two intense bands at 574 and 672 cm-1 whereas pentagonite by a single band at 651 cm-1. The Raman spectrum of cavansite in the hydroxyl stretching region shows bands at 3504, 3546, 3577, 3604 and 3654 cm-1 whereas pentagonite is a single band at 3532 cm_1. These bands are attributed to water coordinated to calcium and vanadium. XPS studies show that bond energy of oxygen in oxides is 530 eV, and in hydroxides -531.5 eV and for water -533.5 eV. XPS studies show a strong peak at 531.5 eV for cavansite, indicating some OH units in the structure of cavansite.

Raman spectroscopic study of the mineral xonotlite Ca 6Si 6O 17(OH) 2-A component of plaster boards

The mineral xonotlite Ca 6Si 6O 17(OH) 2 is a crystalline calcium silicate hydrate which is widely used in plaster boards and in many industrial applications. The structure of xonotlite is best described as having a dreierdoppelketten silicate structure, and describes the repeating silicate trimer which forms the silicate chains, and doppel indicating that two chains combine. Raman bands at 1042 and 1070 cm -1 are assigned to the SiO stretching vibrations of linked units of Si 4O 11 units. Raman bands at 961 and 980 cm -1 serve to identify Si 3O 10 units. The broad Raman band at 862 cm -1 is attributed to hydroxyl deformation modes. Intense Raman bands at 593 and 695 cm -1 are assigned to OSiO bending vibrations. Intense Raman bands at 3578, 3611, 3627 and 3665 cm -1 are assigned to OH stretching vibrations of the OH units in xonotlite. Infrared spectra are in harmony with the Raman spectra. Raman spectroscopy with complimentary infrared spectroscopy enables the characterisation of the building material xonotlite.