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171.
172.
This paper presents an architecture that allows End Users, via the services of Search Engines, to search, in a secure and efficient way, the video content belonging to Content Providers. The search can be accomplished with any searching scheme that the Search Engines wish to provide, as long as certain security constraints are met. However we propose specific algorithms that demonstrate an efficient way to search video data without sacrificing security effectiveness of the system. The search is completed without the End Users or Search Engines needing to purchase the premium content beforehand, and without the Content Providers needing to purchase the search technology. The business motivation of this technique is to assist End Users to purchase content best suiting their requirements—they are offered search results only, not actual content. The objective is to face the problem caused by the current segregation between content ownership and video processing technology ownership. To face this segregation, we present an architecture that guarantees security of Content Provider’s data and Search Engine’s technology and we also present two innovative algorithms that make real time video searching a feasible process. Particularly these algorithms (a) organize video content into a graph based hierarchical structure and (b) perform content guided, non interactive and real time search by exploiting the graph based video structures. The proposed algorithms are incorporated in the presented architecture under the given security constraints. Experimental results and comparisons with conventional techniques are presented to demonstrate the outperformance of the proposed algorithms.
Anastasios DoulamisEmail:
  相似文献   
173.
In this paper, a methodology of general applicability is presented for answering the question if an artist used a number of archetypes to draw a painting or if he drew it freehand. In fact, the contour line parts of the drawn objects that potentially correspond to archetypes are initially spotted. Subsequently, the exact form of these archetypes and their appearance throughout the painting is determined. The method has been applied to celebrated Thera Late Bronze Age wall paintings with full success. It has been demonstrated that the artist or group of artists has used seven geometrical archetypes and seven corresponding well-constructed stencils (four hyperbolae, two ellipses, and one Archimedes' spiral) to draw the wall painting "Gathering of Crocus" in 1650 B.C. This method of drawing seems to be unique in the history of arts and of great importance for archaeology, and the history of mathematics and sciences, as well.  相似文献   
174.
A kinetic mathematical model has been applied to investigate for the first time the effects of Pd particle size on the rates of oxygen back-spillover and CO oxidation during Oxygen Storage Capacity (OSC) measurements under dynamic conditions over Pd/CeO2 catalysts in the 500–700 °C range. The dependence of the intrinsic rate constant k1 of the CO oxidation reaction on PdO, and that of k 2 app of the oxygen back-spillover from ceria to Pd/PdO on the palladium particle size was estimated by performing curve-fitting of the experimental CO and CO2 pulse transient responses obtained. Activation energies of 8.0, 9.5 and 21.1 kJ/mol were calculated for the Eley–Rideal step of CO oxidation for the 1.3, 1.8 and 16.4 nm Pd particles, respectively, supported on CeO2. The transient rates of CO oxidation and oxygen back-spillover were found to decrease with increasing Pd particle size.  相似文献   
175.
Reviews alternate statistical standards of "fair selection," including the standard that seems to be implicit in the federal employee selection guidelines. A human resource planning model is developed to simulate the impact of each standard on minority employment. In the model, the racial composition of the flows of employees into and through the organization is determined by the "fair selection" standard chosen for simulation. The model is applied to staffing data from an existing organization. Data show that the fairness standard implicit in the federal selection guidelines would have a worse effect on Black employment than would the implicit fairness standard typically used by employers. (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
176.
In this article, a new bivariate semiparametric Shewhart‐type control chart is presented. The proposed chart is based on the bivariate statistic (X(r), Y(s)), where X(r) and Y(s) are the order statistics of the respective X and Y test samples. It is created by considering a straightforward generalization of the well‐known univariate median control chart and can be easily applied because it calls for the computation of two single order statistics. The false alarm rate and the in‐control run length are not affected by the marginal distributions of the monitored characteristics. However, its performance is typically affected by the dependence structure of the bivariate observations under study; therefore, the suggested chart may be characterized as a semiparametric control chart. An explicit expression for the operating characteristic function of the new control chart is obtained. Moreover, exact formulae are provided for the calculation of the alarm rate given that the characteristics under study follow specific bivariate distributions. In addition, tables and graphs are given for the implementation of the chart for some typical average run length values and false alarm rates. The performance of the suggested chart is compared with that of the traditional χ2 chart as well as to the nonparametric SN2 and SR2 charts that are based on the multivariate form of the sign test and the Wilcoxon signed‐rank test, respectively. Finally, in order to demonstrate the applicability of our chart, a case study regarding a real‐world problem related to winery production is presented. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
177.
High-performance storage systems are evolving towards decentralized commodity clusters that can scale in capacity, processing power, and network throughput. Building such systems requires: (a) Sharing physical resources among applications; (b) Sharing data among applications; (c) Allowing customized data views. Current solutions typically satisfy the first two requirements through a cluster file-system, resulting in monolithic, hard-to-manage systems. In this paper we present a storage system that addresses all three requirements by extending the block layer below the file-system. First, we discuss how our system provides customized (virtualized) storage views within a single node. Then, we discuss how it scales in clustered setups. To achieve efficient resource and data sharing we support block-level allocation and locking as in-band mechanisms. We implement a prototype under Linux and use it to build a shared cluster file-system. Our evaluation in a 24-node cluster setup concludes that our approach offers flexibility, scalability and reduced effort to implement new functionality.  相似文献   
178.
Dynamic Trust Management   总被引:1,自引:0,他引:1  
Trust management forms the basis for communicating policy among system elements and demands credential checking for access to all virtual private service resources—along with careful evaluation of credentials against specified policies—before a party can be trusted.  相似文献   
179.
In this field note, we detail the operations and discuss the results of an experiment conducted in the unstructured environment of an underwater cave complex using an autonomous underwater vehicle (AUV). For this experiment, the AUV was equipped with two acoustic sonar sensors to simultaneously map the caves' horizontal and vertical surfaces. Although the caves' spatial complexity required AUV guidance by a diver, this field deployment successfully demonstrates a scan‐matching algorithm in a simultaneous localization and mapping framework that significantly reduces and bounds the localization error for fully autonomous navigation. These methods are generalizable for AUV exploration in confined underwater environments where surfacing or predeployment of localization equipment is not feasible, and they may provide a useful step toward AUV utilization as a response tool in confined underwater disaster areas.  相似文献   
180.
We consider the minimum span channel allocation problem encountered in cellular systems. Our solution approach is based on a set of sequential heuristics, and incorporates concepts borrowed from graph coloring schemes. The performance of the new heuristics has been tested on known benchmark problems, whose optimal solutions have been recently quoted in the literature. The new heuristics are quite effective in terms of speed, as well as in terms of spans produced. The results obtained are near-optimal in almost all cases, and certainly comparable to those produced by slower optimization procedures, indicating that these new variations can be treated either as an efficient alternative to this type of problems or as a very good starting point to more complicated procedures.  相似文献   
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