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961.
Flower-like hierarchical ZnO microspheres were successfully synthesized by a simple, template-free, and low-temperature aqueous solution route. The morphology and microstructure of the ZnO microspheres were examined by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The bionic films with hydrophobicity were fabricated by the hierarchical ZnO microspheres modified by stearic acid. It was found that the hydrophobicity of the thin films was very sensitive to the added amount of stearic acid. The thin films modified with 8% stearic acid took on strong superhydrophobicity with a water contact angle (CA) almost to be 178° and weak adhersion. The remarkable superhydrophobicity could be attributed to the synergistic effect of micro/nano hierarchical structure of ZnO and low surface energy of stearic acid. 相似文献
962.
Magnesium doping in hierarchical zinc oxide nanostructures has been carried out using an aqueous method. The XRD results confirmed the hexagonal wurtzite structure for the magnesium doped zinc oxide nanoparticles. On doping with Mg2+, there is a change in morphology of the hierarchical nanostructures to nanorods. The optical absorption and photoluminescence properties of the nanostructures depend on the magnesium doping level. A blue shift of the band gap absorption and the near band edge emission is observed on Mg doping. 相似文献
963.
In multivariate spectral calibration by principal component regression (PCR), the principal components (PCs) are calculated from the response data measured at all employed instrument channels; however some channels are redundant and their responses do not possess useful information. Thus, the extracted PCs possess mixed information from both useful and redundant channels. In this work, we propose a segmentation approach based on unsupervised pattern recognition to identify the most informative spectral region and then to construct a stable multivariate calibration model by PCR. In this method, the instrument channels are clustered into different segments via Kohonen self‐organization map. The spectral data of each segment are then subjected to PCA and the derived PCs are used as input variables for an inverse least square (ILS) regression model employing stepwise selection of the informative PCs. The proposed method was evaluated by the analysis of four simulated and six experimental data sets. It was found that our proposed method can model the above data sets with prediction errors lower than conventional partial least squares (PLS) and PCR methods. In addition, the prediction ability of our method was better than the previously reported models for these data sets. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
964.
Linear codes over finite extension fields have widespread applications in theory and practice. In some scenarios, the decoder has a sequential access to the codeword symbols, giving rise to a hierarchical erasure structure. In this paper we develop a mathematical framework for hierarchical erasures over extension fields, provide several bounds and constructions, and discuss potential applications in distributed storage and flash memories. Our results show intimate connection to Universally Decodable Matrices, as well as to Reed-Solomon and Gabidulin codes. 相似文献
965.
Decision-making in organizations is complex due to interdependencies among decision-makers (agents) within and across organizational hierarchies. We propose a multiscale decision-making model that captures and analyzes multiscale agent interactions in large, distributed decision-making systems. In general, multiscale systems exhibit phenomena that are coupled through various temporal, spatial and organizational scales. Our model focuses on the organizational scale and provides analytic, closed-form solutions which enable agents across all organizational scales to select a best course of action. By setting an optimal intensity level for agent interactions, an organizational designer can align the choices of self-interested agents with the overall goals of the organization. Moreover, our results demonstrate when local and aggregate information exchange is sufficient for system-wide optimal decision-making. We motivate the model and illustrate its capabilities using a manufacturing enterprise example. 相似文献
966.
Menzerath‐Altmann law is a general law of human language stating, for instance, that the longer a word, the shorter its syllables. With the metaphor that genomes are words and chromosomes are syllables, we examine if genomes also obey the law. We find that longer genomes tend to be made of smaller chromosomes in organisms from three different kingdoms: fungi, plants, and animals. Our findings suggest that genomes self‐organize under principles similar to those of human language. © 2009 Wiley Periodicals, Inc. Complexity, 2010 相似文献
967.
Clarence W. de Silva 《Fuzzy Sets and Systems》1995,70(2-3):223-234
Fuzzy logic has been utilized at several hierarchical levels of a typical robotic control system. Four broad levels of application may be identified - task design, system monitoring (including self-tuning and self-organization), information filtering and preprocessing, and in-loop direct control. Even though the need for fuzzy logic is felt mostly at upper levels of the control system, the present applications are mainly concentrated within the lowest level, perhaps driven by convenience rather than necessity. This paper surveys several applications of fuzzy logic in the control of robotic manipulators. Applications are grouped into four hierarchical categories, broadly corresponding to an existing architecture of a robotic control system. Such a classification can be beneficial in ascertaining the appropriateness of fuzzy logic for the specific control task. 相似文献
968.
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970.
Kazuki Osawa Toyoko Imae Masaki Ujihara Atsushi Harada Kanako Ochi Kazuhiko Ishihara Shin‐ichi Yusa 《Journal of polymer science. Part A, Polymer chemistry》2013,51(22):4923-4931
Generation 3.5 poly(amido amine) dendron (G3.5) with 16 n‐butyl terminal groups containing an acrylamide monomer (AaUG3.5) was prepared by condensation between an amino focal group in G3.5 and 11‐acrylamidoundecanoic acid. AaUG3.5 was polymerized using poly(2‐methacryloyloxyethyl phosphorylcholine) (pMPC)‐based macro‐chain transfer agent via reversible addition‐fragmentation chain transfer (RAFT) radical polymerization to obtain amphiphilic diblock copolymers with different compositions. The diblock copolymers (PmDn) were composed of a hydrophilic pMPC block and hydrophobic pendant dendron‐bearing block, where P and D represent pMPC and pAaUG3.5, respectively, and m and n represent the degree of polymerization for each block, respectively. P296D1 and P98D3 formed vesicles and large compound micelles and vesicles, respectively, which was confirmed by light scattering measurements and transmission electron microscopic (TEM) observations. The large compound micelles formed from P98D3 could not incorporate hydrophilic guest polymer molecules, because the aggregates did not have a hydrophilic hollow core. In contrast, the vesicles formed from P269D1 could incorporate hydrophilic guest polymer molecules into the hollow core. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4923–4931 相似文献