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161.
Il Young Song Ju Hong Yoon Seung Hwan Bae Moongu Jeon 《International journal of remote sensing》2013,34(18):5746-5767
In this article, we classify road surface statuses using a Bayesian classification method. This article uses principal component analysis (PCA) that combines a 94 GHz dual-channel polarimetric radiometer. The radiometer is used to investigate the behaviour of the brightness temperature (BT) of different road surface statuses in an open-air laboratory. The aim of this investigation is to characterize four different road surface classes (dry, wet, snowy and icy). Here, the BT (radiothermal emission) characteristics are measured at horizontal and vertical polarizations. For a given database of weather information (including BT, road surface temperature, wind speed, etc.), a PCA subspace is constructed, and the score vectors are classified by solving the Bayesian classification method. As a result, the road surface statuses were found to be well classified by the proposed method in real time. 相似文献
162.
This paper analyses an asymptotic stability of a digitally redesigned control system when the states of the analogue and the digital control systems are approximately matched at every sampling point. The digital redesign is a simple method of converting a given analogue controller to an equivalent digital controller in the sense of state-matching. The concerned state-matching technique is to minimise the norm distance between the discretised closed-loop system matrix of linear analogue control system and that of linear digital control system. It is shown that (i) there exists an upper bound of the norm distance to guarantee the asymptotic stability of the digitally redesigned control system and (ii) the trajectories of the linear analogue and the linear digital control systems coincide at every sampling point if the norm distance is zero. Also, a robustness result is provided in the case that nonlinear perturbations occur in the analogue and the digital control systems. Moreover, design conditions for the developed stability analysis are proposed in terms of linear matrix inequalities. 相似文献
163.
Indium oxide nanoparticles of ~12 nm were synthesized by a simple chemical route using indium(III) nitrate. Nanoparticles are formed after calcining the dried precursor in air at 400 °C for 10 h. TEM analysis showed that the morphology and size of the In2O3 samples were affected by ultrasonication. FTIR and Raman studies reveal that the nanoparticles are single-phase cubic structure of In2O3. NEXAFS study was used to quantify the Indium and oxygen valence state. Magnetic behavior of indium oxide nanoparticles was found to be diamagnetic. UV spectra show a weak band at ~308 nm corresponds to optical band gap energy of 4.03 eV. 相似文献
164.
Do Hwa Jung Sung Jong Bae So Jeong KimKee Suk Nahm Pil Kim 《International Journal of Hydrogen Energy》2011,36(15):9115-9122
We describe how the morphology and electrocatalytic activity of Pt-Pd with low levels of Pt are dependent on the type of Pt precursor that is used for the impregnation on to Pd/C. When a Pt precursor with a negative charge (H2PtCl6) is used in the preparation medium (Pt-Pd/C-H), its electrostatic interaction with the carbon surface results in some Pt nanoparticles being deposited on the carbon separately from the Pd surface. Due to the absence of such an electrostatic interaction with the Pt(NH3)4Cl2 precursor, more selective deposition of Pt can be achieved on the Pd surface (Pt-Pd/C-N). Depending on the morphology, different electrocatalytic performance in oxygen reduction reaction would be observed. Compared to Pt-Pd/C-H, Pt-Pd/C-N shows 180% (half-cell at 0.9 V) and 160% (unit-cell at 0.8 V) enhanced performance, which is comparable to that on Pt/C. It is believed that the interaction between the Pt and the Pd substrate is more extensive in Pt-Pd/C-N than in Pt-Pd/C-H, and this is responsible for the large difference in the catalytic performances between these two catalysts. 相似文献
165.
Cotton fabrics were treated with Biopag, which does not have any functional groups that are reactive toward cellulose, using crosslinking agents or a binder, for the purpose of imparting a durable antimicrobial finish. In this respect, it was found that the crosslinking agents were more effective than the binder. It was confirmed by FT‐IR that the characteristic split peaks of Biopag were still seen even after repeated launderings. The crosslinking agents deteriorated the whiteness and tensile strength of the Biopag‐treated cotton fabrics, while the wrinkle recovery angles (WRAs) were significantly improved. The one‐step padding of Biopag and the crosslinking agent was found to be superior to the two‐step padding method in which Biopag padding was followed by padding of crosslinking agent in respect of WRA, whereas the whiteness and tensile strength were vice versa. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
166.
The effect that hydrostatic pressure has on the decomposition behavior in Cu54Ni6Zr22Ti18 bulk metallic glass (BMG) alloy was assessed using samples, which were isothermally annealed in the supercooled liquid region (SLR) with and without application of hydrostatic pressure. During subsequent annealing for the thermal analysis, the samples annealed under hydrostatic pressure displayed a slower crystallization process in the SLR, which is attributed to a retarded compositional decomposition of the BMG alloy under pressure. 相似文献
167.
For synchrotron X-ray micro-imaging of micro-scale biological flows in organisms, the development of a suitable flow-sensing
tracer is essential for visualizing opaque flows quantitatively. In order to achieve this development in this study, the techniques
employed in three different research fields were integrated namely, X-ray optics for enhancing X-ray concentration, fluid
dynamics to satisfy the flow traceability and drug delivery system to fabricate bio-compatible microcapsules. On the front
burner, we need a special sensor which can be well observed in X-ray micro-imaging and follow working fluid as well. As a
result, bio-compatible micro-scale microcapsule sensors that perform the role of spherical micro lenses were developed. These
novel microcapsules exhibit not only much improved contrast enhancement but also better performance as sensor tracers in micro-scale
flows, compared to conventional solid particles. 相似文献
168.
Min‐Jung Bae Takeshi Ishii Kanako Minoda Yukiko Kawada Tatsuya Ichikawa Taiki Mori Miya Kamihira Tsutomu Nakayama 《Molecular nutrition & food research》2009,53(6):709-715
(–)‐Epigallocatechin gallate (EGCg) is the major component of green tea and is known to show strong biological activity, although it can be easily oxidized under physiological conditions. In this study, we indicate that EGCg is stable in human serum and that human serum albumin (HSA) stabilizes EGCg under aerobic condition. Although EGCg is usually decomposed within 1 h in aqueous solution at neutral pH, EGCg in serum and phosphate buffer (pH 7.4) containing HSA was stable over 1 h, even at neutral and slightly alkaline pH. Under these conditions, EGCg binds to HSA non‐covalently. The sulfhydryl group acts as an antioxidant for EGCg oxidation. Incubation of EGCg with HSA is accompanied by the oxidation of a free sulfhydryl group in HSA. These results suggest that the antioxidant property and the binding capacity of HSA contribute to the stabilization of EGCg in human serum. 相似文献
169.
Structure-property relationships of hydroxy-terminated polyether based polyurethane network 总被引:1,自引:0,他引:1
In the present work, the effect of crosslink density on HTPE networks has been studied in swelling,
thermal and mechanical properties. The solubility parameters of HTPE PUs were obtained by swelling test.
They depended on the molar ratio of N-100 and IPDI and equivalent ratio. It was decreased as the content
of N-100 was lowered. The thermal characteristics of the network polymer were examined by DSC results.
Thermal behavior of HTPE PU network depended on by dangling chain and chain folding in the series using
N-100, with NCO/OH ratio as 1.0, 0.8, 0.6. However, when we performed experiment with IPDI and N-100, with
NCO/OH ratio as 1.0, the thermal properties depended on Mc. Moreover, using IPDI
with N-100 showed enhanced volume specific energy than using only N-100 in tensile test due to strain
induced crystallization. 相似文献
170.
Metallurgical and Materials Transactions B - A thermodynamic equilibrium model is developed for the distribution of nickel between two phases for the system nickel sulfate-acetate... 相似文献