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91.
92.
We address the problem of abnormal behaviour recognition of the inhabitant of a smart home in the presence of unreliable sensors. The corner stone of this work is a two-level architecture sensor fusion based on the Transferable Belief Model (TBM). The novelty of our work lies in the way we detect both unreliable sensors and abnormal behaviour within our architecture by using a temporal analysis of conflict resulting from the fusion of sensors. Detection of abnormal behaviour is based on a prediction/observation process and the influence of the faulty sources is discarded by discounting coefficients. Our architecture is tested in a real-life setting using three heterogeneous sensors enabling the detection of impossible transitions between three possible postures: Sitting, Standing and Lying. The impact of having a faulty sensor management is also tested in the real-life experiment for posture detection.  相似文献   
93.
94.
The behaviors and stresses of an O-ring under uniform squeeze rates and internal pressure change with real time. Therefore, the behaviors and stresses of O-rings under uniform squeeze rates and internal pressures should be studied with real time. To achieve this, a loading device for a transparent type photoelastic experiment, through which various internal pressures and uniform squeeze rates are applied, was developed. The validity of the loading device in analyzing the behaviors and stresses of the O-ring under uniform squeeze rates and internal pressures with real time was verified. It was observed that the filling phenomenon of the O-ring into the space between the lower and front side occurred after forcing out continued for a duration of time. The study also indicated that maximum shear stress would be more effective as a fracture parameter than the maximum normal stress fracture criterion for an O-ring made from rubber.  相似文献   
95.
Synthesis of a polyfluorene/poly(p‐phenylene vinylene) derivative, the Poly [(9,9′‐di‐hexylfluorenediylvinylene‐alt‐1,4‐phenylenevinylene)‐co‐((9,9′‐(3‐t‐butylpropanoate) fluorene‐1,4‐phenylene)] (LaPPS 42) was performed following Wittig and Suzuki routes. Polyfluorenes and derivatives have been used in electroluminescent devices, and the synthesis described here has the advantage in pave the way to get distinct structures having different emission spectra. An extensive study of its electrochemical, thermomechanical, optical, and structural properties was carried out, as well as its application in electroluminescent devices. Polymer light‐emitting diodes (PLEDs) and polymer light‐emitting electrochemical cells (PLECs) were built using LaPPS 42 as active layer, and their electric and optical characterizations confirm they have a potential as active element in electroluminescent devices. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42579.  相似文献   
96.
97.
Journal of Mechanical Science and Technology - The present study focuses on the numerical modelling of gas-jet wiping process. Many processes involving liquids are necessary during steel...  相似文献   
98.
The goal of this paper is to review progress (mostly recent) made in micro and nanovelocimetry, focusing on two techniques: µPIV (microparticle image velocimetry) and nanoPTV (nanoparticle tracking velocimetry). The paper focuses on the measurement of slippage (taken as a benchmark for these techniques), concentrating on work done in our group. We review the developments of µPIV that led, in the last ten years, to the achievement of 100 nm accuracy in the measurement of slip lengths. Later, this approach was complemented by nanoPTV, which recently obtained ±5 nm precision. Here, we also mention recent application of these techniques toward better characterization of microgel and polymer flows. As a whole, the two techniques have conveyed valuable information on flow behavior within and close to the boundaries of microchannels, on the importance of wetting, and on the role of surface heterogeneities. µPIV is commercially available but nanoPTV is not mature. Interesting instrumental developments are expected in the future for the latter technique.  相似文献   
99.
This study aimed to investigate the influence of raw material moisture content on the properties of charcoal from fast-growing Eucalyptus benthamii wood. For that, three treatments were performed with 0, 30, and 50% in relation to the wet basis moisture of the wood samples. The carbonization process used an electric kiln with a heating rate of 1.60°C min?1, initial temperature of 25 to 600°C at the end, kept constant at that temperature for two hours. Variables were statistically analyzed for charcoal yield, non-condensable gases, liquor, and fixed carbon and properties: fixed carbon content, volatile, ash, bulk density, and moisture content of charcoal. According to the results, the charcoal produced from dry wood presented the highest properties, yet the charcoal produced from wood with 30% moisture content showed similar properties.  相似文献   
100.
Tensile properties and crack propagation properties, especially critical strain energy release rate in mode I, GIC, have been used to investigate fracture properties of elastomers and their relationships with microstructure. These investigations were mainly based on a series of comparisons: first, the behaviour of polychloroprene rubber (CR), undergoing stress hardening due to strain induced crystallization (SIC) and oxidative crosslinking (OCL) was compared with that of chlorinated polyethylene (CPE), which undergoes SIC but not OCL, and with a polyurethane based on hydroxyl terminated polybutadiene (PU) which undergoes OCL but not SIC. Comparisons were also made on CR between fracture behaviour at ambient temperature, where SIC occurs and at 100 °C where there is no SIC. Finally, oxidative crosslinking was used to vary in a continuous way the crosslink density in CR and PU, in order to evaluate the role of crosslinking in fracture behaviour.  相似文献   
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