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61.
Thian-Khok YongSek-Sean Tan Chen-Hon NeeSeong-Shan Yap Yeh-Yee KeeGyörgy Sáfrán Zsolt Endre HorváthJason Moscatello Yoke-Khin YapTeck-Yong Tou 《Materials Letters》2012,66(1):280-281
Nanowires of indium tin oxide (ITO) were grown on catalyst-free amorphous glass substrates at relatively low temperature of 250 °C in argon and helium ambient by the Nd:YAG pulsed laser deposition technique. All the ITO samples showed crystalline structure due to substrate heating and the (400) X-ray diffraction peak became relatively stronger as the pressure was increased. The surface morphology was also changed from compact, polycrystalline thin-film layers to a dendritic layer consisting of nanowires for some limited pressure ranges. The transition from the normal thin-film structure to nanowires was likely due to the vapor-liquid-solid mechanism but under catalyst-free condition. These nanowires tended to grow perpendicularly on the glass substrate, as observed with the transmission electron microscopy (TEM), which also confirmed that these nanowires were crystalline. 相似文献
62.
Complying with the objectives of the European Union Water Framework Directive, the water management organisations of Hungary and Serbia launched a common project in 2010 in order to improve the status of the channel crossing the national border. During reconstruction planning they intended to take ecological aspects into consideration. Therefore the evaluation of ecological state has been carried out for the Baja-Bezdan channel complemented by on-the-spot monitoring and biological examinations. Such a detailed survey of the channel has no precedent to date. Besides the evaluation, ecology-based proposals were phrased, which not only serve the sustainable functioning of the channel, but also help to preserve its flora and fauna. 相似文献
63.
Large area OLEDs aimed at lighting applications should provide homogeneous luminance—homogeneity is one of the quality metrics of such devices. Local light generation depends on both the local temperature and the local voltage drop across the light emitting polymer(s) in the device. Therefore the thermal and electrical engineering of OLEDs aimed at lighting applications is critical. Due to the large area of these devices the coupled electrical and the thermal simulation problem is of distributed nature. Electrical characteristics of organic semiconductor materials used in OLED devices are highly nonlinear, and their nonlinear temperature-dependence is significant. In our present approach to distributed electro-thermal field simulation we address special needs of OLEDs, which is not yet the case with widely used, commercially available simulation tools. In this paper we present the latest version of our SUNRED electro-thermal field solver algorithm capable of handling coupled, non-linear electro-thermal problems. The new features of the algorithm are demonstrated by modeling some research OLED samples available to us in the Fast2Light project—this way simulation results are compared against measured data. 相似文献
64.
We show that i-directable nondeterministic automata can be i-directed with a word of length O(2n) for i=1,2, where n stands for the number of states. Since for i=1,2 there exist i-directable automata having i-directing words of length Ω(2n), these upper bounds are asymptotically optimal. We also show that a 3-directable nondeterministic automaton with n states can be 3-directed with a word of length , improving the previously known upper bound O(2n). Here the best known lower bound is . 相似文献
65.
Eric A. Butcher Haitao Ma Ed Bueler Victoria Averina Zsolt Szabo 《International journal for numerical methods in engineering》2004,59(7):895-922
This paper presents a new technique for studying the stability properties of dynamic systems modeled by delay‐differential equations (DDEs) with time‐periodic parameters. By employing a shifted Chebyshev polynomial approximation in each time interval with length equal to the delay and parametric excitation period, the dynamic system can be reduced to a set of linear difference equations for the Chebyshev expansion coefficients of the state vector in the previous and current intervals. This defines a linear map which is the ‘infinite‐dimensional Floquet transition matrix U’. Two different formulas for the computation of the approximate U, whose size is determined by the number of polynomials employed, are given. The first one uses the direct integral form of the original system in state space form while the second uses a convolution integral (variation of parameters) formulation. Additionally, a variation on the former method for direct application to second‐order systems is also shown. An error analysis is presented which allows the number of polynomials employed in the approximation to be selected in advance for a desired tolerance. An extension of the method to the case where the delay and parametric periods are commensurate is also shown. Stability charts are produced for several examples of time‐periodic DDEs, including the delayed Mathieu equation and a model for regenerative chatter in impedance‐modulated turning. The results indicate that this method is an effective way to study the stability of time‐periodic DDEs. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
66.
Tóth IE Wiesel O Tóth DE Boldogkoi Z Halász B Gerendai I 《Microscopy research and technique》2008,71(7):503-509
Previous studies using the viral transneuronal tracing technique demonstrated central autonomic circuits involved in the innervation of the adrenal gland. Since increasing number of data indicate laterality in the neuroendocrine system, we aimed to investigate whether the supraspinal innervation of the adrenal gland exhibits asymmetry or not. The central circuitry involved in the innervation of the left and the right adrenal gland was studied in individual rats by dual transneuronal tracing using isogenic recombinant strains (Ba-DupGreen and Ba-Duplac expressing lacZ) of Bartha strain of pseudorabies virus. Viral infection of brain nuclei (dorsal vagal nucleus, nucleus of the solitary tract, caudal raphe nuclei, A5 cell group, hypothalamic paraventricular nucleus) from the left adrenal was more severe than that from the right organ. Dual-infected neurons were present both in the brain stem and in the hypothalamus. The results indicate a predominance in the supraspinal innervation of the left adrenal gland, and that each adrenal gland is innervated both by side-specific neurons and by neurons that project to both organs. 相似文献
67.
An exact confidence set for two binomial proportions and exact unconditional confidence intervals for the difference and ratio of proportions 总被引:1,自引:0,他引:1
Jen Reiczigel Zsolt Abonyi-Tth Júlia Singer 《Computational statistics & data analysis》2008,52(11):5046-5053
An exact joint confidence set is proposed for two binomial parameters estimated from independent samples. Its construction relies on inverting the minimum volume test, a two-dimensional analogue of Sterne’s test for a single probability. The algorithm involves computer-intensive exact computation based on binomial probabilities. The proposed confidence set has good coverage properties and it performs much better than the likelihood-based confidence set for the same problem. Applying the principle of intersection-union tests, the method can be used to derive exact tests and confidence intervals for functions of the two binomial parameters. Based on this, new exact unconditional two-sided confidence intervals are proposed for the risk difference and risk ratio. The performance of the new intervals is comparable to that of certain well-known confidence intervals in small samples. Extension of the methods described to two hypergeometric or two Poisson variables is straightforward. 相似文献
68.
László A. Jeni András Lőrincz Tamás Nagy Zsolt Palotai Judit Sebők Zoltán Szabó Dániel Takács 《Image and vision computing》2012
Person independent and pose invariant estimations of facial expressions and action unit (AU) intensity estimation are important for situation analysis and for automated video annotation. We evaluated raw 2D shape data of the CK+ database, used Procrustes transformation and the multi-class SVM leave-one-out method for classification. We found close to 100% performance demonstrating the relevance and the strength of details of the shape. Precise 3D shape information was computed by means of constrained local models (CLM) on video sequences. Such sequences offer the opportunity to compute a time-averaged ‘3D personal mean shape’ (PMS) from the estimated CLM shapes, which – upon subtraction – gives rise to person independent emotion estimation. On CK+ data PMS showed significant improvements over AU0 normalization; performance reached and sometimes surpassed state-of-the-art results on emotion classification and on AU intensity estimation. 3D PMS from 3D CLM offers pose invariant emotion estimation that we studied by rendering a 3D emotional database for different poses and different subjects from the BU 4DFE database. Frontal shapes derived from CLM fits of the 3D shape were evaluated. Results demonstrate that shape estimation alone can be used for robust, high quality pose invariant emotion classification and AU intensity estimation. 相似文献
69.
The honey locust gall midge, Dasineura gleditchiae Osten Sacken 1866 (Diptera: Cecidomyiidae) is the main pest of ornamental varieties of the honey locust tree, Gleditsia triacanthos L., in North America, and is now becoming a pest of concern in Europe. Female midges were observed to emerge in the early
morning with their ovipositor extended until they mated. Volatiles were collected from virgin females in a closed-loop stripping
apparatus and analyzed by gas chromatography (GC) coupled to electroantennographic (EAG) recording from the antenna of a male
midge. A single EAG response was observed, which was assumed to be to the major component of the female sex pheromone. This
was identified as (Z)-2-acetoxy-8-heptadecene by comparison of its mass spectrum and GC retention times on different columns with those of synthetic
standards and by micro-analytical reactions. This compound was synthesized, and the individual enantiomers were produced by
kinetic resolution with lipase from Candida antarctica. Analysis of the naturally-produced compound on a cyclodextrin GC column indicated it was the (R)-enantiomer. In EAG dose-response measurements, the (R)-enantiomer alone or in the racemic mixture evoked significant responses from the antennae of male D. gleditchiae, whereas the (S)-enantiomer did not. In field trapping tests, the (R)-enantiomer attracted male D. gleditchiae. The racemic compound was equally attractive, but the (S)-enantiomer was not attractive. Both the pure (R)-enantiomer or racemic (Z)-2-acetoxy-8-heptadecene, applied to red rubber septa in a dose range of 3–30 μg, constitute a strongly attractive bait in
sticky traps for monitoring the flight of D. gleditchiae. 相似文献
70.
Zsolt Kerner 《Corrosion Science》2006,48(8):1899-1911
The main objective of the LIRES (light water reactor reference electrodes) project, supported by the EC within the EURATOM FP5, was to develop reference electrodes, which are robust enough to be used inside a light water reactor at temperatures up to 320 °C and pressures up to 120 bar. This contribution summarises the test of three types of reference electrodes developed within LIRES: (i) an external Ag/AgCl reference electrode from the NRI, Rez, Plc, (ii) a PtIr alloy hydrogen electrode from Studsvik Nuclear AB, and (iii) a Pd-hydride reference electrode—Pd(Pt) polarised active electrode pair—from the VTT Technical Research Centre of Finland. Our results are being compared, within a Round Robin test, with similar measurements of a number of laboratories to select the appropriate reference electrodes for long-term tasks, when the potential should be monitored for months under irradiating conditions. 相似文献