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11.
Cold chain management can optimize freshness and safety to the consumer end. Within FRISBEE European project (http://frisbee-project.eu) a web-based platform was developed for temperature conditions data collection throughout the chilled and frozen food supply chain. Data including all cold chain stages (industry, distributors, retailers and consumers), were collected. This extensive database comprising more than 14,000 time-Temperature (t–T) profiles can serve as a valuable Cold Chain Management tool. The user can define a sequence of cold chain stages for selected food products. The Cold Chain Predictor (CCP) software based on the Cold Chain Database (CCD) allows calculation of product shelf-life status at different cold chain stages based on existing or user defined kinetic data. Conducted field tests expanded the Cold Chain Database and validated the software. The developed tools offer the potential to run simulation scenarios based on real cold chain data and contribute to effective cold chain improvement and management. 相似文献
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文章旨在将不同无线网络、不同通信格式的设备结合起来,从而构建一个面向智能家居的异构网络控制系统。针对不同协议、不同厂家的无线设备难以互通互联、统一控制的问题,本文提出了一种基于Web的中间件软件架构。该中间件进行数据格式转换的同时还能结合Web界面控制设备呈现给用户。上层控制端通过对数据库的操作来实现对不同通信网络智能家居设备的控制和联动。异构无线网络-ARM网关-数据库中间件-控制端的架构能够使用户在避免接触底层硬件系统和软件编程的情况下,快速组网灵活控制智能家居设备,增强了智能家居的系统的易用性。 相似文献
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Data fusion in information retrieval has been investigated by many researchers and a number of data fusion methods have been proposed. However, problems such as why data fusion can increase effectiveness and favorable conditions for the use of data fusion methods are poorly resolved at best. In this paper, we formally describe data fusion under a geometric framework, in which each component result returned from an information retrieval system for a given query is represented as a point in a multi-dimensional space. The Euclidean distance is the measure by which the effectiveness and similarity of search results are judged. This allows us to explain all component results and fused results using geometrical principles. In such a framework, score-based data fusion becomes a deterministic problem. Several interesting features of the centroid-based data fusion method and the linear combination method are discussed. Nevertheless, in retrieval evaluation, ranking-based measures are the most popular. Therefore, this paper investigates the relation and correlation between the Euclidean distance and several typical ranking-based measures. We indeed find that a very strong correlation exists between these. It means that the theorems and observations obtained using the Euclidean distance remain valid when ranking-based measures are used. The proposed framework enables us to have a better understanding of score-based data fusion and use score-based data fusion methods more precisely and effectively in various ways. 相似文献
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《Calphad》2019
The C-Co-Mo-W and C-Mo-Ni-W quaternary systems have been critically evaluated by means of the CALPHAD approach, in which the Co-Mo-W system was readjusted to ensure the model consistency. The thermodynamic models of Gibbs energies for individual phases in the ternary and quaternary systems are described, including substitutional solution model, sublattice model and linear compound model. The modeling covers the whole temperature and composition ranges, and a set of self-consistent thermodynamic parameters for the C-Co-Mo-W and C-Mo-Ni-W quaternary systems is obtained. According to the comprehensive comparisons between the reported and calculated phase diagram data, the reliable equilibria information is satisfactorily accounted for by the modeling. Based on the present work together with the previously reported assessments of binary, ternary and quaternary sub-systems, a thermodynamic database for the C-Co-Mo-Ni-W quinary system is constructed and applied to calculate the sintering region phase equilibria of the (W,Mo)C-(Co,Ni) cemented carbides. 相似文献
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Elastodynamic scattering matrices are known to contain geometrical information about a given scatterer, such as its size and shape. Here, the extent to which this scattered information can be retrieved using an ultrasonic array and used to characterise defects for Non-Destructive Evaluation is explored. Experimentally measured defect scattering matrices are compared to a database of possible scatterers and the nearest neighbour used to characterise the defect's geometry in terms of crack length and orientation. As an example, a database of scattering matrices for small (lengths 0.2–2.0 mm) cracks at a range of frequencies (2–20 MHz) is formed. The short range similarity (i.e. that between close neighbours) and the long range similarity (i.e. uniqueness) are used to understand the uncertainties inherent in this approach. In addition, the effect of spatially coherent noise, such as grain scattering in a polycrystalline metal, on the scattered information content is quantified. It is shown that as the noise level or frequency increases, so the information retrievable from a given crack is reduced, setting bounds on the accuracy of characterisation possible from a given ultrasonic dataset. 相似文献
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Bitmap indexes are commonly used in data warehousing applications such as on-line analytic processing (OLAP). Storing the bitmaps in compressed form has been shown to be effective not only for low cardinality attributes, as conventional wisdom would suggest, but also for high cardinality attributes. Compressed bitmap indexes, such as Byte-aligned Bitmap Compression (BBC), Word-Aligned Hybrid (WAH) and several of their variants have been shown to be efficient in terms of both time and space, compared to traditional database indexes. In this paper, we propose a new technique for compressed bitmap indexing, called Super Byte-aligned Hybrid (SBH) bitmap compression, which improves upon the current state-of-the-art compression schemes. In our empirical evaluation, the query processing time of SBH was about five times faster than that of WAH, while the size of its compressed bitmap indexes was retained nearly close to that of BBC. 相似文献