A hybrid approach to recognising activities of daily living from object use in the home environment

Accurate recognition of Activities of Daily Living (ADL) plays an important role in providing assistance and support to the elderly and cognitively impaired. Current knowledge-driven and ontology-based techniques model object concepts from assumptions and everyday common knowledge of object use for routine activities. Modelling activities from such information can lead to incorrect recognition of particular routine activities resulting in possible failure to detect abnormal activity trends. In cases where such prior knowledge are not available, such techniques become virtually unemployable. A significant step in the recognition of activities is the accurate discovery of the object usage for specific routine activities. This paper presents a hybrid framework for automatic consumption of sensor data and associating object usage to routine activities using Latent Dirichlet Allocation (LDA) topic modelling. This process enables the recognition of simple activities of daily living from object usage and interactions in the home environment. The evaluation of the proposed framework on the Kasteren and Ordonez datasets show that it yields better results compared to existing techniques

TANGENT BUNDLES OF LP-SASAKIAN MANIFOLD ENDOWED WITH GENERALIZED SYMMETRIC METRIC CONNECTION

The aim of the present work is to study and establish conditions for anLP-Sasakian manifold on the tangent bundle $TM$. An LP-Sasakian manifold with the generalized symmetric metric connection on $TM$ is investigated. Next, the curvature tensor and the Ricci tensor of an LP-Sasakian manifold with respect to the generalized symmetric metric connection on $TM$ are calculated. Moreover, the projective curvature tensor with respect to the generalized symmetric metric connection on $TM$ is studied and showed that $TM$ is not $\hat{\xi}^C$-projectively flat. In particular, if $\alpha=0$ and $\beta=1$ then $TM$ is $\hat{\xi}^C$-projectively flat

The effect of variation of molarity of alkali activator and fine aggregate content on the compressive strength of the fly ash: Palm oil fuel ash based geopolymer mortar

The effect of molarity of alkali activator, manufactured sand (M-sand), and quarry dust (QD) on the compressive strength of palm oil fuel ash (POFA) and fly ash (FA) based geopolymermortar was investigated and reported. The variable investigated includes the quantities of replacement levels of M-sand, QD, and conventional mining sand (N-sand) in two concentrated alkaline solutions; the contents of alkaline solution, water, POFA/FA ratio, and curing condition remained constant. The results show that an average of 76% of the 28-day compressive strength was found at the age of 3 days. The rate of strength development from 3 to 7 days was found between 12 and 16% and it was found much less beyond this period. The addition of 100% M-sand and QD shows insignificant strength reduction compared to mixtures with 100% N-sand. The particle angularity and texture of fine aggregates played a significant role in the strength development due to the filling and packing ability. The rough texture and surface of QD enables stronger bond between the paste and the fine aggregate.The concentration of alkaline solution increased the reaction rate and thus enhanced the development of early age strength. The use of M-sand and QD in the development of geopolymer concrete is recommended as the strength variation between these waste materials and conventional sand is not high.Iftekhair Ibnul Bashar, U. Johnson Alengaram, Mohd Zamin Jumaat, and Azizul Isla

Fabrication and Characterization of Graphene-Barium Titanate-Graphene layered capacitors by spin coating at low processing temperatures

Barium titanate, BaTiO3 (BT), materials have been synthesized by two different routes: one ball-mill-derived (BMD) nanopowder and another precursor-derived (PCD) BT synthesis method were used separately to fabricate BT thin films on stainless steel (SS) and quartz substrates by spin coating. Then thin films from both synthesis routes were characterized by Ultraviolet-Visible-Near Infrared (UV-Vis-NIR) Spectroscopy, Field-Emission Scanning Electron Microscopy (FE-SEM), X-ray Diffractometry (XRD), Raman Spectroscopy, and Four-point collinear probe; all carried out at room temperature. Our studies revealed that the PCD synthesis process did not produce the BT phase even under the 900^0C air-annealing condition. In contrast, a homogeneous BT thin film has been formed from the BMD-BT nanopowder. The optical band gap of BMD-BT thin films was found in the 3.10 - 3.28 eV range. Finally, a Graphene-Barium Titanate-Graphene (G-BT-G) structure was fabricated on a SS substrate by spin coating at processing temperatures below 100^0C and characterized by two different pieces of equipment: a Potentiostat/Galvanostat (PG-STAT) and a Precision Impedance Analyzer (PIA). The G-BT-G structure exhibited a capacitance of 8 nF and 7.15 nF, a highest dielectric constant of 800 and 790, and a low dielectric loss of 4.5 and 5, investigated by PG-STAT and PIA equipment, respectively.Comment: 25 pages, 11 Figure

Electrocatalytic and structural properties and computational calculation of PAN-EC-PC-TPAI-I2 gel polymer electrolytes for dye sensitized solar cell application

In this study, gel polymer electrolytes (GPEs) were prepared using polyacrylonitrile (PAN) polymer, ethylene carbonate (EC), propylene carbonate (PC) plasticizers and different compositions of tetrapropylammonium iodide (TPAI) salt. Linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) measurements were done using non-blocking Pt-electrode symmetric cells. The limiting current (Jlim), apparent diffusion coefficient of triiodide ions ðD* I3 Þ and exchange current were found to be 12.76 mA cm2 , 23.41 107 cm2 s 1 and 11.22–14.24 mA cm2 , respectively, for the GPE containing 30% TPAI. These values are the highest among the GPEs with different TPAI contents. To determine the ionic conductivity, the EIS technique was employed with blocking electrodes. The GPE containing 30% TPAI exhibited the lowest bulk impedance, Rb (22 U), highest ionic conductivity (3.62 103 S cm1 ) and lowest activation energy. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques were utilized for structural characterization. Functional group interactions among PAN, EC, PC and TPAI were studied in the FTIR spectra of the GPEs. An up-shift of the XRD peak indicates the polymer–salt interaction and possible complexation of the cation (TPA+ ion) with the lone pair of electrons containing site –C^N at the N atom in the host polymer matrix. On the other hand, computational study shows that TPAI-PAN based GPE possesses the lowest frontier orbital bandgap, which coincided with the enhanced electrochemical and electrocatalytic performance of GPE. The dyesensitized solar cell (DSSC) fabricated with these GPEs showed that the JSC (19.75 mA cm2 ) and VOC (553.8 mV) were the highest among the GPEs and hence the highest efficiency, h (4.76%), was obtained for the same electrolyte