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91.
图像的超分辨率是指利用一幅或者多幅的低分辨率图像,通过相应的算法来获得一幅对应的清晰的高分辨率图像.针对现有的基于学习的超分辨率方法低效率的问题,提出一种基于人工神经网络的快速超分辨率方法,该方法试图利用人工神经网络学习到高分辨率图像和低分辨率图像之间的函数关系,其理论基础来自于人工神经网络能够很好地求解流形学习中高维流形和低维流形之间的映射关系. 相似文献
92.
In the literature, more and more clues show that the bidders indeed tend to risk averse. But as a good structure estimation
procedure in first-price sealed-bid auctions, the traditional PPMLE (Piecewise Pseudo-Maximum Likelihood Estimation) approach
is only applicable to the risk neutrality case. This study generalizes this approach to the risk aversion case, and obtains
a simple estimation procedure for the Pareto family of private costs. In the procedure, the estimation order of distribution
parameters of private costs is not important, which is different from the traditional PPMLE method. Though there is no unique
estimator for θ
1 and γ, some guidance is given for real-world applications on the basis of our Monte Carlo simulation experiments. What’s more,
this procedure can be reduced further, if one is only interested in estimating the private costs. Extensive simulation experimental
results indicate that our approach outperforms or matches at least the traditional one in the case of risk neutrality, and
is applicable to the risk aversion case. 相似文献
93.
Lihua An Sévérien Nkurunziza Daniel Krewski 《Computational statistics & data analysis》2009,53(7):2537-2549
We propose a James-Stein-type shrinkage estimator for the parameter vector in a general linear model when it is suspected that some of the parameters may be restricted to a subspace. The James-Stein estimator is shown to demonstrate asymptotically superior risk performance relative to the conventional least squares estimator under quadratic loss. An extensive simulation study based on a multiple linear regression model and a logistic regression model further demonstrates the improved performance of this James-Stein estimator in finite samples. The application of this new estimator is illustrated using Ontario newborn infants data spanning four fiscal years. 相似文献
94.
Nicolás Peña David Scarlatti Aníbal Ollero 《Journal of Intelligent and Robotic Systems》2009,54(1-3):39-59
The System Wide Information Management (SWIM) approach has been conceived to overcome the capacity and flexibility limitations of the current ATM systems. On the other hand the commercial applications of Unmanned Aerial Vehicles (UAVs) require the integration of these vehicles in the ATM. From this perspective, the unavoidable modernization of the ATM is seen as an opportunity to integrate the UAVs with the rest of the air traffic. This paper is devoted to study the feasibility and impact of the aggregation of UAVs on the future ATM supported by a SWIM inspired architecture. Departing from the existing technical documents that describe the fundamentals of SWIM we have explored the compatibility with a potential UAVs integration and also explored how the UAVs could help to improve the future ATM system. We will use the weather application as an example in both cases. 相似文献
95.
Gerrit K. Janssens An Caris Katrien Ramaekers 《Expert systems with applications》2009,36(3):5987-5991
Congestion on roads leads to uncertainty in travel times, which is important in delivery of goods, especially in a business environment where high levels of customer service are expected. Delivery periods to customers might be constrained by time windows, which makes the scheduling and routing of vehicles from the supplier’s side more difficult. Operations Research methods turn into heuristics for this type of application. But when, on top, uncertainty on travel times are the case, any hope of a simple and well-performing heuristic is lost. This study applies a methodology in which a heuristic is used to find a solution for scheduling and routing under deterministic travel times and, by means of simulation, though the use of Time Petri nets evaluates the sensitivity of the solution to uncertainties in travel times from one customer to the next in a route. 相似文献
96.
TPS中调节控制点的综合应用 总被引:1,自引:1,他引:0
提出了在控制系统更新时,利用新系统的控制功能,实现对老系统中一些特殊控制回路的控制方法.详细介绍了利用Hon-eywell公司HPM中常规控制点的功能,对现场多变量参数求和运算以后进行大可调比参数的控制,以及这种控制回路的控制策略和组态方法.应用结果表明,该控制回路控制精度高、可靠性高.据此提出了充分利用系统软件提供的各种功能模块,解决生产实际问题的方法. 相似文献
97.
98.
99.
Identity based broadcast encryption allows a centralized transmitter to send encrypted messages to a set of identities S, so that only the users with identity in S can decrypt these ciphertexts using their respective private key. Recently [Information Processing Letters 109 (2009)], an identity-based broadcast encryption scheme was proposed (Ren and Gu, 2009) [1], and it was claimed to be fully chosen-ciphertext secure without random oracles. However, by giving a concrete attack, we indicate that this scheme is even not chosen-plaintext secure. 相似文献
100.
X.M. An L.X. Li G.W. Ma H.H. Zhang 《Computer Methods in Applied Mechanics and Engineering》2011,200(5-8):665-674
In the partition of unity (PU)-based methods, the global approximation is built by multiplying a partition of unity by local approximations. Within this framework, high-order approximations are achieved by directly adopting high-order polynomials as local approximations, and therefore nodes along sides or inside elements, which are usually adopted in the conventional finite element methods, are no more required. However, the PU-based approximation constructed in this way may suffer from rank deficiency due to the linear dependence of the global degrees of freedom. In this paper, the origin of the rank deficiency in the PU-based approximation space is first dissected at an element level, and then an approach to predict the rank deficiency for a mesh is proposed together with the principle of the increase of rank deficiency. Finally, examples are investigated to validate the present approach. The current work indicates such a fact that the rank deficiency is an unrelated issue to the nullity of the global matrix. It can be resolved in its own manner. 相似文献