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991.
Today there are many media sharing applications that use diverse metadata formats to describe media resources. This leads to interoperability issues in cataloguing, searching and annotation. This situation poses schema matching algorithms in the eye of the storm of metadata interoperability. In this paper we present two different solutions for multimedia metadata schema matching using variable linkage algorithms. These methods consist in directly comparing the data values stored in the different metadata variables, allowing to overcome the inherent limitations of schema-level matching approaches. We show the feasibility of these methods through some experiments with real metadata information extracted from the image hosting websites Deviantart, Flickr and Picasa. 相似文献
992.
Effect of stress-induced high post-mortem pH on protease activity and tenderness of beef 总被引:1,自引:0,他引:1
Forty-four Swiss Brown young bulls were stressed by regrouping unfamiliar animals before slaughter. M. longissimus thoracis (6-9th ribs) of carcasses were analysed for post-mortem pH, protease activities (m- and α-calpain, calpastatin and cathepsin B + L), Warner-Bratzler shear force and sensory tenderness and juiciness. Muscles were classified into three groups, according to ultimate pH values: > 6.3, 6.3-5.8 and < 5.8. The most significant difference related to high pH was a higher activity of m-calpain at 7th day post mortem. It was also found that meat showing the highest pH was significantly more tender and juicy. Sensory tenderness was highly correlated with activity of m-calpain at 7th day post mortem (r = 0.776) and with ultimate pH (r = 0.708). It is concluded that high ultimate pH induced by stress significantly increases m-calpain activity, and this results in a greatly enhanced tenderisation of beef meat. 相似文献
993.
Julio Alfonso Felix Ortego Rosa Sanchez-Monge Gloria Garcia-Casado Merardo Pujol Pedro Castañera Gabriel Salcedo 《Journal of chemical ecology》1997,23(7):1729-1741
The α-amylase activity was determined throughout the larval development of Spodoptera frugiperda. Maximal activities with optimal pH in the range 8.5–9.5 were found in last instars. Protein preparations enriched in heterotetrameric inhibitors from wheat flour were active towards gut amylases from last instars, while those corresponding to homodimeric and monomeric inhibitors showed low inhibition levels. These results were further supported by testing purified members of each inhibitor type and by analyzing the effects of the inhibitors on the amylase isoenzyme pattern from native PAGE. High levels of trypsin-like activity were also found in gut extracts from last instars. Different genetic variants of the major barley trypsin inhibitor were active against this gut enzyme. None of the other larval digestive protease activities (chymotrypsin-like, elastase-like, leucine aminopeptidase-like, and carboxypeptidase A and B-like) were inhibited, indicating that the barley inhibitor is specific towards trypsin-like enzymes. 相似文献
994.
A thermodynamic model is proposed for the analysis of multicomponent systems capable of homo and heteroassociation between all the chemical species present. Detailed equations have been developed for ternary systems. The method has been applied to the experimental vapour—liquid data obtained for the system formic acid—acetic acid—propionic acid at 760 mm Hg. The calculated activity coefficients were thermodynamically consistent and were correlated using the Redlich—Kister equation. Boiling points, compositions and activity coefficients can be predicted from the vapour—liquid equilibrium data of the three binary systems. 相似文献
995.
This paper addresses the theoretical development and experimental validation of optimized recirculating reverse-flow gas cyclones. The simulation of these systems is based on the predictive properties of a finite diffusivity model, modified to include partial recirculation of the cyclones' emissions.Experimental validation was obtained at laboratory and pilot scales at low temperatures (up to 350 K) and for cork waste biomass boilers at higher temperatures (up to 600 K). Under certain circumstances, with recirculation, the proposed system showed a better performance than an online pulse jet bag filter, and substantially better than with multicyclone systems. The generally observed unexpected high collection of submicron particles, which occurs with inlet concentrations as low as 100 μg/m3, is attributed to turbulent dispersion, either by promoting fine particle capture by larger ones, much like what occurs in recirculating fluidized beds, or by bringing fine particles near the cyclone wall.The extremely fine particle size distributions exiting from the recirculation system, as measured off-line at laboratory, pilot and industrial scales, were confirmed at pilot scale using online measurements through a laser monitor. 相似文献
996.
Jaime Cerdá Pedro C. Pautasso Diego C. Cafaro 《American Institute of Chemical Engineers》2016,62(9):3002-3019
Gasoline blending is a critical process with a significant impact on the total revenues of oil refineries. It consists of mixing several feedstocks coming from various upstream processes and small amounts of additives to make different blends with some specified quality properties. The major goal is to minimize operating costs by optimizing blend recipes, while meeting product demands on time and quality specifications. This work introduces a novel continuous‐time mixed‐integer linear programming (MILP) formulation based on floating time slots to simultaneously optimize blend recipes and the scheduling of blending and distribution operations. The model can handle non‐identical blenders, multipurpose product tanks, sequence‐dependent changeover costs, limited amounts of gasoline components, and multi‐period scenarios. Because it features an integrality gap close to zero, the proposed MILP approach is able to find optimal solutions at much lower computational cost than previous contributions when applied to large gasoline blend problems. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3002–3019, 2016 相似文献
997.
Fermín Marcelo Maciel‐Barboza Leonel Soriano‐Equigua Jaime Sánchez‐García Francisco Rubén Castillo‐Soria Victor Hugo Castillo Topete 《ETRI Journal》2016,38(1):62-69
In this paper, we propose two novel user selection algorithms for multiuser multiple‐input and multiple‐output downlink wireless systems, in which both a base station (BS) and mobile stations (MSs) are equipped with multiple antennas. Linear transmit beamforming at the BS and receive combining at the MSs are used to avoid interference between users and find a better sum‐rate capacity performance. An optimal technique for selecting users would entail an exhaustive search, which in practice becomes computationally complex for a realistic number of users. Suboptimal algorithms with low complexity are proposed for a coordinated beamforming scheme. Simulation results show that the performance of the proposed algorithms is better than that provided by previous algorithms and is very close to an optimal approach with reduced complexity. 相似文献
998.
The doctoral program in Computing and Information Sciences and Engineering (CISE) of the University of Puerto Rico is a research and education program intended to form investigators and build the academic field of computing and informatics with a comprehensive, multidisciplinary and integrative view. The program is based on the premise that the impact of computing and informatics on science and engineering goes beyond the mere empowering of data analysis and simulation capabilities. Indeed, computing and informatics offer a new approach to discovery and engineering design, which we call the informatics approach. We believe that the philosophy and methodology of data representation and processing exerts a decisive influence on what can be achieved in science and engineering, and in the scope and quality of results. The doctoral program in CISE is intended to catalyze this approach as an academic discipline. This article describes the main features, driving forces, and projections of this doctoral program. 相似文献
999.
Sudeep K. Lahiri Javier Bonet Jaime Peraire Lluis Casals 《International journal for numerical methods in engineering》2005,63(10):1371-1395
In this paper we present a fractional time‐step method for Lagrangian formulations of solid dynamics problems. The method can be interpreted as belonging to the class of variational integrators which are designed to conserve linear and angular momentum of the entire mechanical system exactly. Energy fluctuations are found to be minimal and stay bounded for long durations. In order to handle incompressibility, a mixed formulation in which the pressure appears explicitly is adopted. The velocity update over a time step is split into deviatoric and volumetric components. The deviatoric component is advanced using explicit time marching, whereas the pressure correction for each time step is computed implicitly by solving a Poisson‐like equation. Once the pressure is known, the volumetric component of the velocity update is calculated. In contrast with standard explicit schemes, where the time‐step size is determined by the speed of the pressure waves, the allowable time step for the proposed scheme is found to depend only on the shear wave speed. This leads to a significant advantage in the case of nearly incompressible materials and permits the solution of truly incompressible problems. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
1000.
Mei Yang Yan Huang Jaime Kim Meejeong Lee Tatsuya Suda Matsubara Daisuke 《Computer Communications》2005,28(18):2034-2046
This paper proposes a new QoS framework, called the On-Demand QoS Path framework (ODP). It provides end-to-end QoS guarantees to individual flows with minimal overhead, while keeping the scalability characteristic of DiffServ. ODP exercises per-flow admission control and end-to-end bandwidth reservation at the edge of the network and only differentiates service types in the core of the network. In addition, to adapt to dynamically changing traffic load, ODP monitors the bandwidth utilization of the network and performs dynamic bandwidth reconfiguration in the network core based on the monitored bandwidth utilization. Through extensive simulations, the performance of ODP is investigated and compared with that of IntServ and DiffServ frameworks. The simulation results clearly showed that ODP provides end-to-end QoS guarantees to individual flows, which DiffServ can not provide, with much less overhead than IntServ. 相似文献