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Multi-operator image resizing can preserve important objects and structure in an image by combining multiple image resizing operators. However, traditional multi-operator methods do not take both horizontal and vertical content-aware resizing potential into consideration, which essentially leads to squeeze/stretch effect in the resultant images. In this paper, we propose a new multi-operator scheme that addresses aforementioned issue by integrating direct and indirect seam carving. Compared with previous methods, the proposed scheme remarkably reduces the cost of deciding when to change operators, by employing a newly defined image artifact measure. Furthermore, we propose a novel seam carving enhancement, named ACcumulated Energy Seam Carving (ACESC), as a basic operator to improve global structure preservation. By combining horizontal and vertical seam carving, our scheme preserves the shapes of important objects well. We present typical results to demonstrate the effectiveness of our method. User study shows that our method has high user preference. 相似文献
996.
Many applications of wireless sensor networks monitor the physical world and report events of interest. To facilitate event
detection in these applications, in this paper we propose a pattern-based event detection approach and integrate the approach
into an in-network sensor query processing framework. Different from existing threshold-based event detection, we abstract
events into patterns in sensory data and convert the problem of event detection into a pattern matching problem. We focus
on applying single-node temporal patterns, and define the general patterns as well as five types of basic patterns for event
specification. Considering the limited storage on sensor nodes, we design an on-node cache manager to maintain the historical
data required for pattern matching and develop event-driven processing techniques for queries in our framework. We have conducted
experiments using patterns for events that are extracted from real-world datasets. The results demonstrate the effectiveness
and efficiency of our approach. 相似文献
997.
Personalized recommender systems which can provide people with suggestions according to individual interests usually rely on Collaborative Filtering (CF). The neighborhood based model (NBM) is a common choice when implementing such recommenders due to the intuitive nature; however, the recommendation accuracy is a major concern. Current NBM based recommenders mostly address the accuracy issue based on the rating data alone, whereas research on hybrid recommender systems suggests that users enjoy specifying feedback about items across multiple dimensions. In this work we aim to improve the accuracy of NBM via integrating the folksonomy information. To achieve this objective, we first propose the folksonomy network (FN) to analyze the item relevance described by the folksonomy data. We subsequently integrate the obtained folksonomy information into the global-optimization based NBM for making multi-source based recommendations. Experiments on the MovieLens dataset suggest positive results, which prove the efficiency of our strategy. 相似文献
998.
Xin Luo Huijun Liu Gaopeng Gou Yunni Xia Qingsheng Zhu 《Engineering Applications of Artificial Intelligence》2012,25(7):1403-1412
Collaborative Filtering (CF) can be achieved by Matrix Factorization (MF) with high prediction accuracy and scalability. Most of the current MF based recommenders, however, are serial, which prevent them sharing the efficiency brought by the rapid progress in parallel programming techniques. Aiming at parallelizing the CF recommender based on Regularized Matrix Factorization (RMF), we first carry out the theoretical analysis on the parameter updating process of RMF, whereby we can figure out that the main obstacle preventing the model from parallelism is the inter-dependence between item and user features. To remove the inter-dependence among parameters, we apply the Alternating Stochastic Gradient Solver (ASGD) solver to deal with the parameter training process. On this basis, we subsequently propose the parallel RMF (P-RMF) model, of which the training process can be parallelized through simultaneously training different user/item features. Experiments on two large, real datasets illustrate that our P-RMF model can provide a faster solution to CF problem when compared to the original RMF and another parallel MF based recommender. 相似文献
999.
This paper presents an integration technology for RF passives using benzocyclobutene (BCB)/metal multilayer interconnection
for system-in-package applications. This technology has been specially developed for RF subsystem packages in which a thick
polymer, BCB (more than 15 μm thick), is adopted as dielectric with lossy silicon as substrate for its excellent characteristics.
Both dry-etch BCB and photosensitive BCB are applied in this work, and their processes are briefly introduced and compared.
An RF power divider, an MIM capacitor, different types of RF inductors as well as a coupled microstrip based band-pass filter
are fabricated and measured at wafer level. The results show good electrical performances, and accordingly the passives are
well applicable in RF band. Moreover, the subsystem models including monolithic chips connected with passives are presented. 相似文献
1000.
In order to reduce the computation of complex problems, a new surrogate-assisted estimation of distribution algorithm with
Gaussian process was proposed. Coevolution was used in dual populations which evolved in parallel. The search space was projected
into multiple subspaces and searched by sub-populations. Also, the whole space was exploited by the other population which
exchanges information with the sub-populations. In order to make the evolutionary course efficient, multivariate Gaussian
model and Gaussian mixture model were used in both populations separately to estimate the distribution of individuals and
reproduce new generations. For the surrogate model, Gaussian process was combined with the algorithm which predicted variance
of the predictions. The results on six benchmark functions show that the new algorithm performs better than other surrogate-model
based algorithms and the computation complexity is only 10% of the original estimation of distribution algorithm. 相似文献