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41.
Wearable cameras can gather large amounts of image data that provide rich visual information about the daily activities of the wearer. Motivated by the large number of health applications that could be enabled by the automatic recognition of daily activities, such as lifestyle characterization for habit improvement, context-aware personal assistance and tele-rehabilitation services, we propose a system to classify 21 daily activities from photo-streams acquired by a wearable photo-camera. Our approach combines the advantages of a late fusion ensemble strategy relying on convolutional neural networks at image level with the ability of recurrent neural networks to account for the temporal evolution of high-level features in photo-streams without relying on event boundaries. The proposed batch-based approach achieved an overall accuracy of 89.85%, outperforming state-of-the-art end-to-end methodologies. These results were achieved on a dataset consists of 44,902 egocentric pictures from three persons captured during 26 days in average.  相似文献   
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43.
The formation and characteristics of a parasitic conduction band barrier located at a SiGe/Si heterojunction have been investigated using a commercial numerical simulator and a simple, three-region model of a heterojunction with a nearby p–n junction. The barrier’s formation is examined as a function of the displacement of the p–n junction from the heterojunction, but also found to depend on the germanium concentration, junction doping and the applied bias. The phenomenon is of interest for understanding the performance of SiGe/Si heterojunction bipolar transistors, where the p–n junction is intentionally displaced from the heterojunction at either the emitter or collector junctions or where boron outdiffusion from the base produces p–n junction displacement. The barrier is found to scale with the germanium mole fraction and to be significantly larger when the heterojunction is displaced into the p-side of the p–n junction. Beyond some minimum separation of the junctions, the barrier height rises with junction displacement and saturates. For a given displacement, the barrier’s height can be suppressed with reverse bias or enhanced by forward bias of the p–n junction. The results of the numerical simulations are compared with those from a simple analytical model as an aid in understanding the barrier’s formation and characteristics.  相似文献   
44.
1. The effects of tachykinins and capsaicin were studied by means of intracellular membrane potential and isometric tension recordings in the isolated trachea of the guinea-pig. 2. The basal membrane potential averaged -51 mV, and most preparations demonstrated spontaneous slow waves. Tetraethylammonium (TEA), a potassium channel blocker (8 x 10(-3) M), depolarized the membrane potential to -44 mV and induced a rhythmic activity. 3. In control solution, substance P (10(-8)-10(-6) M), [Nle10]-neurokinin A(4-10) (10(-8)-10(-6) M) and capsaicin (10(-7)-10(-6) M) induced concentration-dependent depolarizations which were statistically significant at the highest concentration tested (depolarization by 10(-6) M: 8, 11 and 16 mV for the NK1 agonist, the NK2 agonist and capsaicin, respectively). 4. In the presence of TEA (8 x 10(-3) M), the three substances induced depolarizations which were statistically significant at the highest concentration tested for substance P (10(-6) M) and at 10(-7) and 10(-6) M for both [Nle10]-neurokinin A(4-10) and capsaicin (depolarization by 10(-6) M: 11, 17 and 10 mV for substance P, [Nle10]neurokinin A(4-10) and capsaicin, respectively). 5. In the presence or absence of tetraethylammonium, [MePhe7]-neurokinin B (10(-8)-10(-6) M) did not induce any significant changes in membrane potential. 6. The depolarizing effects of substance P (10(-6) M) and [Nle10]-neurokinin A(4-10) (10(-6) M) were blocked only by the specific antagonists for NK1 and NK2 receptors, SR 140333 (10(-7) M) and SR 48968 (10(-7) M), respectively. The effects of capsaicin (10(-6) M) were partially inhibited by each antagonist and fully blocked by their combination. 7. Substance P (10(-9) to 10(-4) M), [Nle10]-neurokinin A(4-10) (10(-10) to 10(-5) M), [MePhe7]-neurokinin B and capsaicin (10(-7) to 10(-5) M) evoked concentration-dependent contractions. 8. The contractions to substance P were significantly inhibited by SR 140333 (10(-8) to 10(-6) M) but unaffected by SR 48968 (10(-8) to 10(-6) M). Furthermore, the response to [Nle10]-neurokinin A(4-10) was significantly inhibited by SR 48968 and unaffected by SR 140333 at the same concentrations. Although SR 48968 (10(-7) M) alone did not influence the effects of substance P, it potentiated the inhibitory effect of SR 140333 (10(-7) M). A similar synergetic effect of these two compounds was observed in the inhibition of the contractile response to [Nle10]-neurokinin A(4-10). 9. Neither SR 140333 (10(-7) M) nor SR 48968 (10(-7) M) alone influenced the contractions to [MePhe7]-neurokinin B and capsaicin. However, the combination of the two antagonists abolished the contractions to either peptide. 10. These results demonstrate that the stimulation of both NK1 and NK2 tachykinin-receptors induced contraction and depolarization of the guinea-pig tracheal smooth muscle and that both receptors were stimulated during the endogenous release of tachykinins by capsaicin. There was no evidence for a major role of NK3 receptors in the contractile and electrical activity of the guinea-pig isolated trachea.  相似文献   
45.
We present a heuristic method for learning error correcting output codes matrices based on a hierarchical partition of the class space that maximizes a discriminative criterion. To achieve this goal, the optimal codeword separation is sacrificed in favor of a maximum class discrimination in the partitions. The creation of the hierarchical partition set is performed using a binary tree. As a result, a compact matrix with high discrimination power is obtained. Our method is validated using the UCI database and applied to a real problem, the classification of traffic sign images.  相似文献   
46.
A strategy for removal of heavy metals and phenol from wastewaters is proposed. It involves consecutive cation biosorption by fungi, phenol biodegradation by the yeast association Candida sp. 2326 + Candida sp. 2327 and regeneration. Copper and cobalt removal from aqueous solutions containing 80-120 mg/L phenol by biosorption, using Rhizopus archizus cells immobilized onto poly (vinyl alcohol), was investigated by conducting a series of batch experiments. The removal efficiencies were 81% for Cu and 5% for Co. The residual concentrations of Cu (1.9 mg/L) and of Co (9.5 mg/L) did not change the biodegradation dynamics of phenol. A quantitative biodegradation of 120 mg/L phenol proceeded within 22 h. After biodegradation of phenol, the removal efficiencies achieved by biosorption after regeneration were 90% for Cu and 44% for Co. It was found that copper and cobalt form positively charged complexes with phenol. This complex formation hinders the retention of Cu and Co by the biosorbent and reduces the uptake of their cations.  相似文献   
47.
Zusammenfassung Es wurde eine Analyse der Weißbrot-Aromastoffe durch die kombinierte gaschromatographische Massenspektralmethode durchgeführt. Es wurden 29 organische Verbindungen identifiziert. 20 davon werden zum erstenmal im Brotaroma nachgewiesen. Diese neuermittelten Verbindungen sind: 1,1-Diäthoxyisopentan, 2-Phenyläthylformiat,n-Buthylformiat, 2-Isooctenal, 2-Octenon-4, sec-Nonanol, Nonanol-1, 2-Nonenon-4, 2-Decenon-4, 2-Decenon-5, 1-Dodecenon-3, 2-Dodecenon-4, 2-Dodecenon-5, Dodecanol, Octylacetat, Äthylbenzoat, Nitrobenzol, Pentadecanon-2, Heptadecanon-2, Tridecadien.
Gas-chromatographic-mass-spectral analysis of aroma-compounds of bread
Summary Analysis of aroma compunds of whithe bread by means of a combined gas-chromatographicmass-spectral method was carried out. 29 organic compounds were identified, 20 of which were reported for the first time in bread aroma. These for the first time reported compounds are: 1,1-diethoxyisopentane, 2-phenylethylformiate,n-butylformate, 2-isooctenal, 2-octenone-4, sec. nonanol, nonanol-1, 2-nonanone-4, 2-decenone-4, 2-decenone-5, 1-dodecenone-3, 2-dodecenone-4, 2-dodecenone-5, dodecanol, octylacetate, ethylbenzoate, nitrobenzene, pentadecanone-2, heptadecanone-2, tridecadiene.
  相似文献   
48.
Coping with complexity is an important issue in both research and industry. One strategy to deal with complexity is separation of concerns, which can be addressed using aspect-oriented paradigm. Despite being well researched in programming, this paradigm is still in a preliminary stage in the area of business process management (BPM). While some efforts have been made to introduce aspect orientation in business process modelling, there is no holistic approach with a formal underlying foundation to support aspect-oriented business process design and enactment, and this gap restricts aspect-oriented paradigm from being practically deployed in the area of BPM. Therefore, this paper proposes a sound systematic approach which builds on a formal syntax for modelling aspect-oriented business processes and a Petri Net-based operational semantics for enacting these processes. The approach enables the implementation of software system artefacts as a proof of concept to support design and enactment of aspect-oriented business processes in practice. The approach is demonstrated using a banking case study, where processes are modelled using a concrete notation that conforms to the proposed formal syntax and then executed in a state-of-the-art BPM system where the implemented artefacts are deployed.  相似文献   
49.
New quaternary telluride glassy materials with composition of GexSb40−xS50Te10 and GexSb40−xS55Te5 (x = 10, 20, and 27) have been synthesized and their optical properties have been studied by means of spectroscopic ellipsometry in the range of 400–820 nm. The optical constants, i.e. the refractive index, extinction coefficient, absorption coefficient, and the optical band gap energy are determined and their compositional dependence is considered. These parameters are characteristics for amorphous structure of the synthesized glasses, revealed from the neutron diffraction measurements.  相似文献   
50.
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