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91.
Monitoring the Dynamic Process of Formation of Plasmonic Molecular Junctions during Single Nanoparticle Collisions 下载免费PDF全文
Jing Guo Jie Pan Shuai Chang Xuewen Wang Na Kong Wenrong Yang Jin He 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(15)
The capability to study the dynamic formation of plasmonic molecular junction is of fundamental importance, and it will provide new insights into molecular electronics/plasmonics, single‐entity electrochemistry, and nanooptoelectronics. Here, a facile method to form plasmonic molecular junctions is reported by utilizing single gold nanoparticle (NP) collision events at a highly curved gold nanoelectrode modified with a self‐assembled monolayer. By using time‐resolved electrochemical current measurement and surface‐enhanced Raman scattering spectroscopy, the current changes and the evolution of interfacial chemical bonding are successfully observed in the newly formed molecular tunnel junctions during and after the gold NP “hit‐n‐stay” and “hit‐n‐run” collision events. The results lead to an in‐depth understanding of the single NP motion and the associated molecular level changes during the formation of the plasmonic molecular junctions in a single NP collision event. This method also provides a new platform to study molecular changes at the single molecule level during electron transport in a dynamic molecular tunnel junction. 相似文献
92.
在满足机构许用压力角条件下,采用0.618法最优确定盘状摆动凸轮机械的最小基圆半径。 相似文献
93.
The effect of a carbon containing atmosphere on the microstructure and mechanical properties of Fe-32Mn-9.4Al-1C-1.27Si alloy was investigated in this work. Surface oxide nodules and grain boundary oxides were found to form on this alloy when it was annealed in carbon-containing air at 1050 °C for 1 h. The oxidation reaction was thought to be the result of the green rot attack process. This alloy was embrittled severely by the carbon-containing air through the formation of surface oxide nodules and grain boundary oxide. The carbon-containing air enhanced the oxidation rate of this alloy at 1050 °C. The structure of the oxide nodules formed on this alloy in the carbon-containing air was similar to that observed on a FeMnAl alloy heated in 1000 °C air for 24 h. 相似文献
94.
To provide both a high payload capacity and a good stego-image quality, a high payload frequency-based reversible image hiding (HPFRIH) method was presented in this paper. These performances can be achieved by transforming a cover image from the spatial domain into the frequency domain through Haar digital wavelet transform (HDWT) method followed by an adaptive arithmetic coding method to encode the HDWT coefficients in a high-frequency band. The HPFRIH method was used to conceal both the compressed data and the secret data in the high-frequency band. This simple method can completely reconstruct the cover image only from the stego-image. Moreover, experimental results showed that the HPFRIH method offers both impressive hiding capacity and satisfied stego-image quality. 相似文献
95.
96.
Sentiment-oriented contextual advertising 总被引:2,自引:2,他引:0
Web advertising (Online advertising), a form of advertising that uses the World Wide Web to attract customers, has become
one of the world’s most important marketing channels. This paper addresses the mechanism of Content-based advertising (Contextual advertising), which refers to the assignment of relevant ads to a generic web page, e.g., a blog post. As blogs become a platform for
expressing personal opinion, they naturally contain various kinds of expressions, including both facts and comments of both
a positive and negative nature. Besides, in line with the major tenet of Web 2.0 (i.e., user-centric), we believe that the web-site owners would be willing to be in charge of the ads which are positively related to their contents.
Hence, in this paper, we propose the utilization of sentiment detection to improve Web-based contextual advertising. The proposed
sentiment-oriented contextual advertising (SOCA) framework aims to combine contextual advertising matching with sentiment
analysis to select ads that are related to the positive (and neutral) aspects of a blog and rank them according to their relevance.
We experimentally validate our approach using a set of data that includes both real ads and actual blog pages. The results
indicate that our proposed method can effectively identify those ads that are positively correlated with the given blog pages. 相似文献
97.
Logistic regression in sealed-bid auctions with multiple rounds: Application in Korean court auction
This paper proposes a forecasting method for court auction information system using logistic regression model with heterogeneity across the multiple round. The goal is to predict whether an individual auction item in a certain round will be sold or not. A simple linear regression and the least angle regression (LARS) containing random effect terms were used to select meaningful variables for our logit model. The link function of the proposed logit model is represented by two bundles of parameters. The former part consists of the parameters whose values do not change over rounds. The latter part has parameters whose values interact with rounds. The observed data corresponding to an appraiser price as well as an intercept term reflecting local characteristics are used without any change. Data that corresponds to all the other parameters is not directly used, but transformed based on similarities between the original item and the surrounding auction items being recommended by the court auction experts. We tested the Bayesian logistic regression by establishing different priors: Dunson’s prior, Gelman’s prior and Ansari’s prior. Dunson’s prior was found to perform the best. Little significant difference was found between the results of the other two priors. These findings indicate that logistic regression taking the heterogeneity of multi-round into account performs better than a one-layered neural network over all time periods. 相似文献
98.
Dong-Xia Chang Author Vitae Xian-Da Zhang Author Vitae Author Vitae 《Pattern recognition》2009,42(7):1210-1987
In this paper, a new clustering algorithm based on genetic algorithm (GA) with gene rearrangement (GAGR) is proposed, which in application may effectively remove the degeneracy for the purpose of a more efficient search. A new crossover operator that exploits a measure of similarity between chromosomes in a population is also presented. Adaptive probabilities of crossover and mutation are employed to prevent the convergence of the GAGR to a local optimum. Using the real-world data sets, we compare the performance of our GAGR clustering algorithm with K-means algorithm and other GA methods. An application of the GAGR clustering algorithm in unsupervised classification of multispectral remote sensing images is also provided. Experiment results demonstrate that the GAGR clustering algorithm has high performance, effectiveness and flexibility. 相似文献
99.
100.
The electronic structures of quasi-one-dimensional ferrimagnetic Ca3Co2O6 are investigated using the generalized gradient approximation (GGA) as well as the GGA plus on-site Coulomb interaction (GGA+U) scheme. GGA+U calculations reveal that the interchain ferrimagnetic Ca3Co2O6 is a Mott–Hubbard insulator rather than a metal given from GGA. In addition, we found an on-site U induced 3z2−r2 orbital ordering on Copri sublattice which drives the intrachain ferromagnetic coupling along c-axis. Our findings suggest that strong electron-electron correlation plays an important role in Ca3Co2O6. 相似文献