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101.
Li Zhang Ming Jiang Dewan Farid M.A. Hossain 《Expert systems with applications》2013,40(13):5160-5168
Automatic perception of human affective behaviour from facial expressions and recognition of intentions and social goals from dialogue contexts would greatly enhance natural human robot interaction. This research concentrates on intelligent neural network based facial emotion recognition and Latent Semantic Analysis based topic detection for a humanoid robot. The work has first of all incorporated Facial Action Coding System describing physical cues and anatomical knowledge of facial behaviour for the detection of neutral and six basic emotions from real-time posed facial expressions. Feedforward neural networks (NN) are used to respectively implement both upper and lower facial Action Units (AU) analysers to recognise six upper and 11 lower facial actions including Inner and Outer Brow Raiser, Lid Tightener, Lip Corner Puller, Upper Lip Raiser, Nose Wrinkler, Mouth Stretch etc. An artificial neural network based facial emotion recogniser is subsequently used to accept the derived 17 Action Units as inputs to decode neutral and six basic emotions from facial expressions. Moreover, in order to advise the robot to make appropriate responses based on the detected affective facial behaviours, Latent Semantic Analysis is used to focus on underlying semantic structures of the data and go beyond linguistic restrictions to identify topics embedded in the users’ conversations. The overall development is integrated with a modern humanoid robot platform under its Linux C++ SDKs. The work presented here shows great potential in developing personalised intelligent agents/robots with emotion and social intelligence. 相似文献
102.
103.
An experimentally validated, two-dimensional, axisymmetric, numerical model of micro-tubular, single-chamber solid oxide fuel cell (MT-SC-SOFC) has been developed. The model incorporates methane full combustion, steam reforming, dry reforming and water-gas shift reaction followed by electrochemical oxidation of produced hydrogen within the anode. On the cathode side, parasitic combustion of methane along with the electrochemical oxygen reduction is implemented. The results show that the poor performance of single-chamber SOFC as compared to the conventional (dual-chamber) SOFC (in case of micro-tubes) is due to the mass transport limitation on the anode side. The gas velocity inside the micro-tube is far too low when compared to the gas-chamber inlet velocity. The electronic current density is also non-uniform over the cell length, mainly due to the short length of the anode current collector located at the cell outlet. Furthermore, the higher temperature near the cell edges is due to the methane combustion (very close to the cell inlet) and current collection point (at the cell outlet). Both of these locations could be sensitive to the silver current collecting wire as silver may rupture due to cell overheating. 相似文献
104.
The present paper deals with a theoretical analysis of the spray cooling of a Reactor Pressure Vessel (RPV) head in a Boiling Water Reactor (BWR). To this end a detailed computational model has been developed. The model predicts the trajectories, diameters and temperatures of subcooled droplets moving in saturated vapor. The model has been validated through comparison with experimental data, in which droplet temperatures were measured as functions of the distance that they cover in saturated vapor from the moment they leave the sprinkler outlet to the moment they impact on the RPV head inner wall. The calculations are in very good agreement with measurements, confirming the model adequacy for the present study. The model has been used for a parametric study to investigate the influence of several parameters on the cooling efficiency of the spray system. Based on the study it has been shown that one of the main parameters that govern the temperature increase in a subcooled droplet is its initial diameter. Comparisons are also made between conclusions from the theoretical model and observations made through flow and temperature measurements in the plant (Forsmark 1 and 2). One of these observations is that the rate at which the RPV head temperature decreases on the way down from hot to cold standby is constant and independent of the sprinkling flow rate as long as the flow rate is above a certain minimum value. Accordingly, the theoretical model shows that if one assumes that the cooling of the RPV head is through a water film built on the inner wall due to sprinkling, the heat removal rate is only very weakly dependent on the sprinkling flow rate. 相似文献
105.
H Farid E H Adelson 《Journal of the Optical Society of America. A, Optics, image science, and vision》1999,16(9):2136-2145
The image of an object can vary dramatically, depending on lighting, specularities, reflections, and shadows. It is often advantageous to separate these incidental variations from the intrinsic aspects of an image. We describe a method for photographing objects behind glass and digitally removing the reflections from the surface of the glass, leaving the image of the objects behind the glass intact. We describe the details of this method, which employs simple optical techniques and independent component analysis and show its efficacy with several examples. 相似文献
106.
Blind inverse gamma correction 总被引:5,自引:0,他引:5
The luminance nonlinearity introduced by many imaging devices can often be described by a simple point-wise operation (gamma correction). This paper presents a technique for blindly estimating the amount of gamma correction in the absence of any calibration information or knowledge of the imaging device. The basic approach exploits the fact that gamma correction introduces specific higher-order correlations in the frequency domain. These correlations can be detected using tools from polyspectral analysis. The amount of gamma correction is then estimated by minimizing these correlations. 相似文献
107.
Farid Debieb Luc Courard Said Kenai Robert Degeimbre 《Construction and Building Materials》2009,23(11):3382-3387
Recycling waste building materials from construction and demolition (C&D) sites is increasingly investigated for economical and environmental reasons. Roller compacted concrete (RCC) is a special dry concrete mix; laid down and compacted like a soil, it is especially used for the construction of massive structures like dams or large horizontal surfaces like road foundation. In this paper, natural concrete slabs were cured in water, sea water, chloride solutions or sulphate solutions and then crushed to obtain virgin and contaminated (polluted) recycled aggregates. The aim of this research is the total replacement (100% coarse and fine) of natural aggregates (NA) by recycled concrete aggregates (RA) in the composition of a roller compacted concrete. The natural and recycled aggregates are characterised and compared. The mechanical properties and durability performances of concrete with contaminated RA are analysed. The experimental results showed that the polluted RA are much richer in chlorides than in sulphates and are leached if they are soaked in water. Significant differences were observed between the properties of original and new concrete and the results demonstrated the need of taking these contaminations into account. 相似文献
108.
Muhammad Iqbal Bhanger Shahid Iqbal Farooq Anwar Muhammad Imran Mubeena Akhtar & Muhammad Zia-ul-Haq 《International Journal of Food Science & Technology》2008,43(5):779-786
Methanolic extracts of rice bran (MRB) were found to be the richest in phenolics than all the other extraction media, i.e. water, 80% methanol, 70% ethanol, diethyl ether. Thermal stability of MRB was determined by evaluating antioxidant activity of heated extracts in linoleic acid system. Cookies were prepared in sunflower oil premixed with MRB at different concentrations, i.e. 500, 1000 and 2000 ppm, and with butylated hydroxytoluene and α‐tocopherol at 200 ppm. Oxidative stability of cookies was measured by storing under ambient conditions for an year with periodical analysis after every 2 months. Fatty acid composition was determined by gas–liquid chromatography. A regular decrease in unsaturated fatty acids (USFA) and increase in saturated fatty acids was observed with the increase in storage period; all the stabilised samples showed appreciably less decrease in USFA than that of control sample. Induction period ranged from 14.73 to 31.22 h while control exhibited 7.5 h. Peroxide value, iodine value and free fatty acids were chosen as the parameters for quality evaluation of cookies. Results suggest rice bran to be a potential source of antioxidants for stabilisation of cookies. 相似文献
109.
We present two detailed studies concerning thedmt and the multichannelhemt for power amplifications. Each work comprises a first theoretical part where the structure is optimized by simulating the device. Technological realizations are hence performed at the laboratory. The following measurements give results very encouraging and permit to foresee the superior performance relatively to that of GaAs powermesfet. 相似文献
110.
Momin Khan Akhtar Nadhman Walayat Shah Imran Khan Masoom Yasinzai 《IET nanobiotechnology / IET》2019,13(5):477
This study was aimed to develop a self‐nanoemulsifying drug delivery system (SNEDDS) for amphotericin B (AmB) potential use in leishmaniasis through topical and oral routes. Two formulations, formulation A and formulation B (FA and FB) of AmB loaded SNEDDS were developed by mixing their excipients through vortex and sonication. The SNEDDS formulation FA and FB displayed a mean droplet size of 27.70 ± 0.5 and 30.17 ± 0.7 nm and zeta potential −11.4 ± 3.25 and −13.6 ± 2.75 mV, respectively. The mucus permeation study showed that formulation FA and FB diffused 1.45 and 1.37%, respectively in up to 8 mm of mucus. The cell permeation across Caco‐2 cells monolayer was 10 and 11%, respectively. Viability of Caco‐2 cells was 89% for FA and 86.9% for FB. The anti‐leishmanial activities of FA in terms of IC50 were 0.017 µg/ml against promastigotes and 0.025 µg/ml against amastigotes, while IC50 values of FB were 0.031 and 0.056 µg/ml, respectively. FA and FB killed macrophage harboured Leishmania parasites in a dose‐dependent manner and a concentration of 0.1 µg/ml killed 100% of the parasites. These formulations have the potential to provide a promising tool for AmB use through oral and topical routes in leishmaniasis therapy.Inspec keywords: nanomedicine, drops, microorganisms, electrokinetic effects, cellular biophysics, drug delivery systems, monolayers, drugs, diseasesOther keywords: self‐nanoemulsifying drug delivery system, topical routes, oral routes, SNEDDS formulation, mucus permeation study, cell permeation, leishmaniasis treatment, amphotericin B, zeta potential, Caco‐2 cell monolayer, vortex, sonication, droplet size, Caco‐2 cell viability, antileishmanial activity, promastigotes, amastigotes, Leishmania parasites 相似文献