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51.
A novel method based on fusion of texture and shape information is proposed for facial expression and Facial Action Unit (FAU) recognition from video sequences. Regarding facial expression recognition, a subspace method based on Discriminant Non-negative Matrix Factorization (DNMF) is applied to the images, thus extracting the texture information. In order to extract the shape information, the system firstly extracts the deformed Candide facial grid that corresponds to the facial expression depicted in the video sequence. A Support Vector Machine (SVM) system designed on an Euclidean space, defined over a novel metric between grids, is used for the classification of the shape information. Regarding FAU recognition, the texture extraction method (DNMF) is applied on the differences images of the video sequence, calculated taking under consideration the neutral and the expressive frame. An SVM system is used for FAU classification from the shape information. This time, the shape information consists of the grid node coordinate displacements between the neutral and the expressed facial expression frame. The fusion of texture and shape information is performed using various approaches, among which are SVMs and Median Radial Basis Functions (MRBFs), in order to detect the facial expression and the set of present FAUs. The accuracy achieved using the Cohn–Kanade database is 92.3% when recognizing the seven basic facial expressions (anger, disgust, fear, happiness, sadness, surprise and neutral), and 92.1% when recognizing the 17 FAUs that are responsible for facial expression development. 相似文献
52.
Providing context-aware Web services is an adaptive process of delivering contextually matched Web services to meet service requesters’ needs. We define the term “context” from two perspectives: one from service requesters; and the other from Web services. From the former perspective, context is defined as the surrounding environment affecting requesters’ services discovery and access, such as requesters’ preferences, locations, activities, and accessible network and devices. From the latter perspective, context is defined as the surrounding environment affecting Web services delivery and execution, such as networks and protocols for service binding, devices and platforms for service execution, and so on. This paper presents a Java Expert System Shell (JESS)-enabled context elicitation system featuring an ontology-based context model that formally describes and acquires contextual information pertaining to service requesters and Web services. Based on the context elicitation system, we present a context-aware services-oriented architecture for providing context-aware Web service request, publication, and discovery. Implementation details of the context elicitation system and the evaluation results of context-aware service provision are also reported. 相似文献
53.
Cáceres-Criado Irene García-Molina Diego Francisco Mesas-Carrascosa Francisco Javier Triviño-Tarradas Paula 《Virtual Reality》2023,27(2):967-983
Virtual Reality - Virtual reconstruction is defined as the visual recovery of a building or object through the creation of a three-dimensional model of the asset to be reconstructed, in a... 相似文献
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Warren RE 《Applied optics》1996,35(21):4180-4193
Differential absorption lidar (DIAL) is a well-established technology for estimating the concentration and its path integral CL of vapor materials using two closely spaced wavelengths. The recent development of frequency-agile lasers (FAL's) with as many as 60 wavelengths that can be rapidly scanned motivates the need for detection and estimation algorithms that are optimal for lidar employing these new sources. I derive detection and multimaterial CL estimation algorithms for FAL applications using the likelihood ratio test methodology of multivariate statistical inference theory. Three model sets of assumptions are considered with regard to the spectral properties of the backscatter from either topographic or aerosol targets. The calculations are illustrated through both simulated and actual lidar data. 相似文献
57.
MA Warren 《Canadian Metallurgical Quarterly》1996,55(12):276-277
The St. Francis Hospice Program is symbolic of more than 100 years of Franciscan dedication to the people of Hawaii. Since Mother Marianne's arrival in November of 1883, the Sisters of the Third Franciscan Order Syracuse, New York have responded to the calling; "the charity of Christ impels us." It is through this calling that care and comfort for the terminally ill is a part of the mission of St. Francis Healthcare System. The magnificent spirit through which Hospice services have been made possible, is a reflection of God's great generosity to us throughout the years. 相似文献
58.
We review the literature on approximate dynamic programming, with the goal of better understanding the theory behind practical algorithms for solving dynamic programs with continuous and vector-valued states and actions and complex information processes. We build on the literature that has addressed the well-known problem of multidimensional (and possibly continuous) states, and the extensive literature on model-free dynamic programming, which also assumes that the expectation in Bellman’s equation cannot be computed. However, we point out complications that arise when the actions/controls are vector-valued and possibly continuous. We then describe some recent research by the authors on approximate policy iteration algorithms that offer convergence guarantees (with technical assumptions) for both parametric and nonparametric architectures for the value function. 相似文献
59.
C-PSA: Constrained Pareto simulated annealing for constrained multi-objective optimization 总被引:2,自引:0,他引:2
In recent years, evolutionary algorithms (EAs) have been extensively developed and utilized to solve multi-objective optimization problems. However, some previous studies have shown that for certain problems, an approach which allows for non-greedy or uphill moves (unlike EAs), can be more beneficial. One such approach is simulated annealing (SA). SA is a proven heuristic for solving numerical optimization problems. But owing to its point-to-point nature of search, limited efforts has been made to explore its potential for solving multi-objective problems. The focus of the presented work is to develop a simulated annealing algorithm for constrained multi-objective problems. The performance of the proposed algorithm is reported on a number of difficult constrained benchmark problems. A comparison with other established multi-objective optimization algorithms, such as infeasibility driven evolutionary algorithm (IDEA), Non-dominated sorting genetic algorithm II (NSGA-II) and multi-objective Scatter search II (MOSS-II) has been included to highlight the benefits of the proposed approach. 相似文献
60.
Derrick K. Rollins Nidhi Bhandari Jim Kleinedler Kaylee Kotz Amber Strohbehn Lindsay Boland Megan Murphy Dave Andre Nisarg Vyas Greg Welk Warren E. Franke 《Journal of Process Control》2010,20(1):95-107
The goal of this work is to present a causation modeling methodology with the ability to accurately infer blood glucose levels using a large set of highly correlated noninvasive input variables over an extended period of time. These models can provide insight to improve glucose monitoring, and glucose regulation through advanced model-based control technologies. The efficacy of this approach is demonstrated using real data from a type 2 diabetic (T2D) subject collected under free-living conditions over a period of 25 consecutive days. The model was identified and tested using eleven variables that included three food variables as well as several activity and stress variables. The model was trained using 20 days of data and validated using 5 days of data. This gave a fitted correlation coefficient of 0.70 and an average absolute error (AAE) (i.e., the average of the absolute values for the measured glucose concentration minus modeled glucose concentration) of 13.3 mg/dL for the validation data. This AAE result was significantly better than the subject’s personal glucose meter AAE of 15.3 mg/dL for replicated measurements. 相似文献