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991.
In this paper, the optical properties of the silicon nano-cone-hole (NCH) structure array are studied. The ultimate efficiency of the optimized NCH array is enhanced by 23.11% compared to an optimized nanohole array of the same thickness. The absorptance enhancement of the NCH arrays is attributed to its lowered reflectance, more supported resonant modes, and enhanced mode interaction. The angular dependence of ultimate efficiency is also investigated. 相似文献
992.
Xiaoyan Gao Yanchao Zhu Xu ZhaoZichen Wang Dongmin AnYuejia Ma Shuang GuanYanyan Du Bing Zhou 《Applied Surface Science》2011,257(10):4719-4724
In order to achieve good dispersion of nano-SiO2 and increase the interactions between nano-SiO2 and PU matrix, nano-SiO2 was firstly modified with poly(propylene glycol) phosphate ester (PPG-P) which was a new polymeric surfactant synthesized through the esterification of poly(propylene glycol) (PPG) and polyphosphoric acid (PPA). Then a series of polyurethane (PU)/SiO2 nanocomposites were prepared via in situ polymerization. The surface modification of nano-SiO2, the microstructure and the properties of nanocomposites were investigated by FTIR, SEM, XRD and TGA. It was found that good dispersion of nano-SiO2 achieved in PU/SiO2 nanocomposite after the modification with PPG-P. The segmented structures of PU were not interfered by the presence of nano-SiO2 in these nanocomposites. 相似文献
993.
We use the dielectric-response formalism to evaluate the induced density of charge carriers in supported graphene due to an external moving charged particle in terms of its velocity and distance from graphene for several equilibrium charge carrier densities due to graphene doping. We show that, when the particle speed exceeds a threshold value, an oscillatory wake effect develops in the induced charge density trailing the particle. Strong effects are observed in the wake pattern due to finite size of the graphene–substrate gap, as well as due to strong coupling effects, and plasmon damping of graphene?s π electrons. 相似文献
994.
In this paper, we study cooperative behavior among mobile agents; the agents have heterogenous view radii and they play the prisoner’s dilemma game with those being within their vision fields. It is found that the cooperation level is remarkably promoted when the heterogeneity of view radii is considered, and the degree distribution of the system is investigated to explain this interesting phenomenon. Moreover, we report that the cooperative behavior is best favored by low density, moderate view radius, and small moving speed. Our findings may be helpful in understanding cooperative behavior in natural and social systems consisting of mobile agents. 相似文献
995.
Wang Yifu Yin Jingchan Yuan Guishan Dong Xiaochun Du Chunlei 《Applied Physics A: Materials Science & Processing》2011,104(4):1243-1247
A tunable metamaterial by employing I-shaped metamaterial with loaded varactor diode is presented in this paper and the phase
of emitting wave modulated by the varactor diode is demonstrated. We have proved that the energy loss is relatively low when
the working frequency is chosen to be away from the resonance frequency of the I-shaped metamaterial. By using the metamaterial,
a pattern reconfigurable antenna is designed based on arrayed antennas theory. Simulations results show that the radiation
pattern can be tuned to different angles by properly arranging the linear phase difference of adjacent regions. 相似文献
996.
Three models for the aggregated stochastic processes based on an underlying continuous-time Markov repairable system are developed in which two-part partition of states is used. Several availability measures such as interval availability, instantaneous availability and steady-state availability are presented. Some of these availabilities are derived by using Laplace transforms, which are more compact and concise. Other reliability-distributions for these three models are given as well. 相似文献
997.
The traditional hypothesis of “rationality” is far from perfect. Models of fairness solely based on consequence cannot explain why the same consequence of an action is perceived and reciprocated differently. A reciprocity model which accounts for both consequence and its underlying intention is presented in this paper to illustrate the effect of intention in a traditional dyadic channel where one supplier plays a Stackelberg-like game with one retailer. This research aims to investigate how reciprocity may affect the members’ decisions and the channel’s coordination. In this study, two scenarios are discussed: (1) the retailer has a preference for reciprocity while the supplier does not and (2) both the retailer and the supplier have a preference for reciprocity. Results for acrimonious supply chain (γμ>1) and harmonious supply chain (γμ?1) are analyzed. Furthermore, we derive equilibria under the two scenarios and prove the existence and the uniqueness of the equilibria. The results show that intention plays an important role in decision making of the supply chain and will significantly change the equilibria. Moreover, an acrimonious supply chain can be coordinated with a simple wholesale-price contract under certain conditions, which can never happen in a traditional channel. A harmonious supply chain, however, cannot be coordinated in any way. 相似文献
998.
This paper proposes a novel extended traffic network model to solve the logit-based stochastic user equilibrium (SUE) problem with elastic demand. In this model, an extended traffic network is established by properly adding dummy nodes and links to the original traffic network. Based on the extended traffic network, the logit-based SUE problem with elastic demand is transformed to the SUE problem with fixed demand. Such problem is then further converted to a linearly constrained convex programming and addressed by a predictor–corrector interior point algorithm with polynomial complexity. A numerical example is provided to compare the proposed model with the method of successive averages (MSA). The numerical results indicate that the proposed model is more efficient and has a better convergence than the MSA. 相似文献
999.
The notion of mixed quermassintegrals in the classical Brunn-Minkowski theory is extended to that of Orlicz mixed quermassintegrals in the Orlicz Brunn-Minkowski theory. The analogs of the classical Cauchy-Kubota formula, the Minkowski isoperimetric inequality and the Brunn-Minkowski inequality are established for this new Orlicz mixed quermassintegrals. 相似文献
1000.
Hui Zhang Junxiang Xu Fubao Zhang Miao Du 《Central European Journal of Mathematics》2014,12(10):1484-1499
For a class of asymptotically periodic Schrödinger-Poisson systems with critical growth, the existence of ground states is established. The proof is based on the method of Nehari manifold and concentration compactness principle. 相似文献