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201.
Cooperative relaying is considered as an effective technique to enlarge the coverage area and enhance the system capacity for the future wireless systems. In this paper, an infrastructure based multi-antenna cooperative relay network has been investigated. Closed form expressions of outage probability and average error rate have been derived, when the relay and the destination perform selection combining of the signals. The relay is assumed to operate in the adaptive decode and forward mode. The effect of number of antennas installed on the relay and their placement has also been studied. 相似文献
202.
Dissipation of a two-mode squeezed vacuum state in the single-mode amplitude damping channel
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We explore how a two-mode squeezed vacuum state sechθ ea+b+ tanh θ |00> evolves when it undergoes a singlemode amplitude dissipative channel with rate of decay κ. We find that in this process not only the squeezing parameter decreases, tanh θ → e-κt tanh θ, but also the second-mode vacuum state evolves into a chaotic state exp{b+bln[1 - e-2κt tanh2 θ]}. The outcome state is no more a pure state, but an entangled mixed state. 相似文献
203.
204.
The effects of electromigration on copper in carbon nanotube (CNT) channels are investigated using molecular dynamics simulations. The study shows that the potential energy of copper and the resistive forces on copper are dependent on the shape of the CNT junction, and the increase in bias voltages magnifies these effects. Bias voltages affect the density of copper in the downstream CNT. The velocity of copper in the downstream CNT is relatively lower than that in the upstream CNT when the biased voltage is high. 相似文献
205.
206.
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
207.
Hernán R. Henríquez Verónica Poblete Juan C. Pozo 《Journal of Mathematical Analysis and Applications》2014
In this paper we establish the existence of mild solutions for a non-autonomous abstract semi-linear second order differential equation submitted to nonlocal initial conditions. Our approach relies on the existence of an evolution operator for the corresponding linear equation and the properties of the Hausdorff measure of non-compactness. 相似文献
208.
We study the second order Emden–Fowler type differential equation in the super-linear case α<β. Using a Hölder-type inequality, we resolve the open problem on the possible coexistence on three possible types of nononscillatory solutions (subdominant, intermediate, and dominant solutions). Jointly with this, sufficient conditions for the existence of globally positive intermediate solutions are established. Some of our results are new also for the Emden–Fowler equation. 相似文献
(a(t)|x′|αsgnx′)′+b(t)|x|βsgnx=0
209.
In this paper, we consider a class of nonlocal stochastic Kuramoto–Sivashinsky equations driven by additive noises. Under some appropriate conditions, we investigate long time behavior, i.e., stability and growth bounds of the solutions to the equation. Finally, several examples are given to illustrate our results. 相似文献
210.
We will analyze mixed-0/1 second-order cone programs where the continuous and binary variables are solely coupled via the conic constraints. We devise a cutting-plane framework based on an implicit Sherali–Adams reformulation. The resulting cuts are very effective as symmetric solutions are automatically cut off and each equivalence class of 0/1 solutions is visited at most once. Further, we present computational results showing the effectiveness of our method and briefly sketch an application in optimal pooling of securities. 相似文献