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1.
Despite much work on Universal Multimedia Experience (UME), existing video adaptation approaches cannot yet be considered as truly user-centric, mostly due to their poor handling of semantic user preferences. Indeed, these works mainly concentrate on lower-level user preferences but do neither consider any fine-grained object-level adaptation nor evaluate different adaptation options based on predicted user expectations. Moreover, these works do not provide owners with property rights that enable them to place restrictions on the types of modifications to be made to the video content. To address these shortcomings, we propose the Personalized vIdeo Adaptation Framework (PIAF) for high-level semantic video adaptation. PIAF is a fully integrated framework providing all the requirements for a semantic video adaptation. It defines a video annotation model and a user profile model comprising semantic constraints that are delineated in a consistent way, based on the standards MPEG-7 and MPEG-21. At the heart of the framework, the Adaptation Decision Taking Engine (ADTE) computes utility values for different adaptation options, considering each shot separately. The corresponding utility function evaluates the possible choices by evaluating multiple parameters that capture different dimensions of a multimedia experience: amount of modified content, modifications to key objects and shots with respect to the semantic integrity of the original content, expected processing cost of the adaptation, and the anticipated visual and temporal quality of the adapted content. Furthermore, the ADTE can deal with intellectual property issues by selecting an adaptation plan of good quality that also satisfies constraints specified by the content owner. This paper places a significant emphasis on theoretical details of the utility function and the computation of the adaptation plan. It also presents the results and evaluation of the adaptation process both in simulation and user study.  相似文献   
2.
It is shown that the pole-zero configuration of relevant families of second-order continuous-time transfer functions is preserved after sampling. The results are valid for any sampling period and give tighter bounds for the location of the sample zero than those reported in earlier literature. These results complement the analysis made by T. Soderstrom (ibid., vol.35, p.1249-53, 1990) on the zero location of second-order sampled systems  相似文献   
3.
A novel metal-supported solid oxide fuel cell has been developed that is capable of operating at temperatures of 500–600 °C. The rationale behind the materials used to construct this fuel cell type is given, and results are presented from cell testing on hydrogen and reformed natural gas, including durability trials of some 2500 h duration. This new fuel cell variant is shown to be tolerant of carbon monoxide, durable, robust to thermal and redox cycling, and capable of delivering technologically relevant power densities. This paper was presented at the Fuel Cells: Materials, Processing, and Manufacturing Technologies Symposium sponsored by the Energy/Utilities Industrial Sector & Ground Transportation Industrial Sector and the Specialty Materials Critical Technologies Sector at the ASM International Materials Solutions Conference, October 13–15, 2003, in Pittsburgh, PA. The symposium was organized by P. Singh, Pacific Northwest National Laboratory, S.C. Deevi, Philip Morris USA, T. Armstrong, Oak Ridge National Laboratory, and T. Dubois, U.S. Army CECOM.  相似文献   
4.
In everyday life, people use a large diversity of hand configurations while reaching out to grasp an object. They tend to vary their hands position/orientation around the object and their fingers placement on its surface according to the object properties such as its weight, shape, friction coefficient and the task they need to accomplish. Taking into account these properties, we propose a method for generating such a variety of good grasps that can be used for the accomplishment of many different tasks. Grasp synthesis is formulated as a single constrained optimization problem, generating grasps that are feasible for the hand’s kinematics by minimizing the norm of the joint torque vector of the hand ensuring grasp stability. Given an object and a kinematic hand model, this method can easily be used to build a library of the corresponding object possible grasps. We show that the approach is adapted to different representations of the object surface and different hand kinematic models.  相似文献   
5.
This paper proposes a novel strategy for grasping 3D unknown objects in accordance with their corresponding task. We define the handle or the natural grasping component of an object as the part chosen by humans to pick up this object. When humans reach out to grasp an object, it is generally in the aim of accomplishing a task. Thus, the chosen grasp is quite related to the object task. Our approach learns to identify object handles by imitating humans. In this paper, a new sufficient condition for computing force-closure grasps on the obtained handle is also proposed. Several experiments were conducted to test the ability of the algorithm to generalize to new objects. They also show the adaptability of our strategy to the hand kinematics.  相似文献   
6.
Influence of zero locations on the number of step-response extrema   总被引:1,自引:0,他引:1  
A new bounding theorem for the number of extrema that may occur in the step-response of a stable linear system is presented. The derivation of an easily-computed upper bound is given to complement literature results which have previously established the existence of a lower bound. The theorem requires knowledge of the pole-zero configuration of the transfer-function and is applicable to stable systems with real zeros and real poles.  相似文献   
7.
Daily pattern and rates of whole-body tyrosine oxidation and phenylalanine hydroxylation were determined in young adults (15 men, 1 woman) receiving [13C]tyrosine and [(2)H2]phenylalanine via primed, constant oral infusion and [(2)H4]tyrosine by vein (five subjects also received [(2)H3]leucine simultaneously by vein) continuously for 24 h (12 h fast then 12 h fed). Subjects were given a diet supplying 96.6 (n = 5), 35.6 (the proposed requirement; n = 5), and 18.5 mg phenylalanine x kg(-1) x d(-1) (n = 6) based on an otherwise adequate L-amino acid mixture for 6 d before the 24-h tracer study began. [Each diet was low in tyrosine: 6.79 mg x kg(-1) x d(-1).] Our hypothesis was that subjects would be in tyrosine equilibrium, positive balance, or both, at the 96.6- and 35.6-mg intakes and in distinctly negative balance at the 18.5-mg intake. The diurnal pattern in phenylalanine and tyrosine kinetics was dependent on the intake and, presumably, on the adequacy of dietary phenylalanine. Wholebody tyrosine balances, determined from rates of phenylalanine hydroxylation and tyrosine input and oxidation were negative (0.05 < P < 0.1 from zero balance) with the low (18.5 mg) phenylalanine intake [total aromatic amino acid (AAA) intake: 25.3 mg x kg(-1) x d(-1)] but at equilibrium (P > 0.05 from zero balance) with the two higher phenylalanine intakes. Whole-body AAA balance (AAA intake - tyrosine oxidation) was negative (P < 0.05 from zero balance) with the low intake, at equilibrium with the intermediate intake, and apparently distinctly positive (P < 0.05) with the generous intake. Despite model limitations, as discussed, these findings lend further support for a proposed, tentative value for a total mean requirement of 39 mg AAA x kg(-1) x d(-1).  相似文献   
8.
Shelf life and safety concerns of bakery products--a review   总被引:2,自引:0,他引:2  
Bakery products are an important part of a balanced diet and, today, a wide variety of such products can be found on supermarket shelves. This includes unsweetened goods (bread, rolls, buns, crumpets, muffins and bagels), sweet goods (pancakes, doughnuts, waffles and cookies) and filled goods (fruit and meat pies, sausage rolls, pastries, sandwiches, cream cakes, pizza and quiche). However, bakery products, like many processed foods, are subject to physical, chemical and microbiological spoilage. While physical and chemical spoilage limits the shelf life of low and intermediate moisture bakery products, microbiological spoilage by bacteria, yeast and molds is the concern in high moisture products i.e., products with a water activity (a(w)) > 0.85. Furthermore, several bakery products also have been implicated infoodborne illnesses involving Salmonella spp., Listeria monoctyogenes and Bacillus cereus, while Clostridium botulinum is a concern in high moisture bakery products packaged under modified atmospheres. This extensive review is divided into two parts. Part I focuses on the spoilage concerns of low, intermediate and high moisture bakery products while Part II focuses on the safety concerns of high moisture bakery products only. In both parts, traditional and novel methods of food preservation that can be used by the bakery industry to extend the shelf life and enhance the safety of products are discussed in detail.  相似文献   
9.
In this paper, a review of recent journal articles on passive, active, semi-active, and hybrid vibration control of structures subjected to dynamic loading is presented. Passive systems reviewed include tuned mass damper (TMD), tuned liquid column damper (TLCD), tuned liquid column ball damper (TLCBD), circular TLCD (CTLCD), and pendulum TLCD (PTLCD). Active control systems include active tuned mass dampers (ATMD) and piezoelectric actuators. Semi-active systems include magnetorheological (MR) damper, negative stiffness devices (NSD), magneto-rheological damper TMD (MR-TMD), variable stiffness semi-active TMD (VS-STMD), variable damper STMD (VD-STMD), and recentering variable friction device (RVFD). Hybrid systems include active base isolation system and semi-active MR dampers with nonlinear base isolators. The current frontier of research is semi-active control of structures as well hybridization of various control systems. The problem is complex requiring integration of several different hardware and software technologies with structural design such as smart materials, adaptive dampers, actuators, sensors, and control and signal processing algorithms. This complexity also makes it an exciting area of research and development.  相似文献   
10.
OBJECTIVE: We wanted to determine the prevalence and appearance of elastofibroma dorsi in an elderly patient population (n = 258) who underwent CT of the chest for reasons other than to evaluate posterolateral chest wall pain, stiffness, or a mass. CONCLUSION: Five elastofibromas were detected in four patients; none of these elastofibromas were noted at initial examination. Our study suggests that the prevalence of elastofibroma dorsi revealed by CT is 2%, which is lower than the 11-24% found in autopsy series but higher than expected for such a rare tumor. Elastofibroma dorsi typically has a layered appearance on CT; however, in our study, homogeneous soft-tissue attenuation was noted. The diagnosis is often missed prospectively. Familiarity with the location and imaging appearance of elastofibroma dorsi may enhance detection and characterization of posterolateral chest wall masses in elderly patients.  相似文献   
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