Quality measures for ETL processes: from goals to implementation

Extraction transformation loading (ETL) processes play an increasingly important role for the support of modern business operations. These business processes are centred around artifacts with high variability and diverse lifecycles, which correspond to key business entities. The apparent complexity of these activities has been examined through the prism of business process management, mainly focusing on functional requirements and performance optimization. However, the quality dimension has not yet been thoroughly investigated, and there is a need for a more human-centric approach to bring them closer to business-users requirements. In this paper, we take a first step towards this direction by defining a sound model for ETL process quality characteristics and quantitative measures for each characteristic, based on existing literature. Our model shows dependencies among quality characteristics and can provide the basis for subsequent analysis using goal modeling techniques. We showcase the use of goal modeling for ETL process design through a use case, where we employ the use of a goal model that includes quantitative components (i.e., indicators) for evaluation and analysis of alternative design decisions.Peer ReviewedPostprint (author's final draft

Contribution of geostatistics to predict bird diversity in Gouraya National Park (Algeria)

The present study emphasizes the contribution of geostatistics techniques in ornithology. We used kriging interpolation to predict avian diversity in the Gouraya National Park. The punctual index abundance method was used to census birds based on a grid network (250 m x 250 m). An exploratory analysis with the variogram has characterized the spatial variability of studied variable. The ordinary kriging was used to realize diversity map prediction which shows the spatial behaviour trend of this variable. The standard deviation map has given an assessment of the quality of the estimate. The diversity map prediction is thus an important tool for decision support directly applicable to the management and conservation of birds in Gouraya National ParkLa présente étude a fait ressortir l'apport des techniques géostatistiques en ornithologie. Pour ce faire, nous avons utilisé l'interpolation par krigeage pour prédire la diversité avienne sur l'ensemble du territoire du parc national de Gouraya (Algérie). La méthode des indices ponctuels d'abondance a été utilisée pour le dénombrement des oiseaux sur la base d'un réseau à maille carrée de 250 m x 250 m. Une analyse exploratoire par le biais du variogramme a permis la modélisation du comportement spatial de la variable étudiée. Le krigeage ordinaire a été retenu pour la réalisation de la carte de prédiction de la diversité avienne. Cette carte fait apparaître les zones à forte diversité avienne. La carte des écarts-types a donné une appréciation de la qualité de l'estimation. La carte de prédiction de la diversité avienne constitue ainsi un outil important d'aide à la décision directement applicable en matière de gestion et de conservation de l'avifaune du parc national de Gouraya

Structural and textural features of TiO2/SAPO-34 nanocomposite prepared by the sol–gel method

This paper focuses on the synthesis of nanocomposite materials, TiO2/SAPO-34, using the sol–gel method, which involves preparing a mixture between as-synthesized or calcined SAPO-34 zeolite and TiO2 gel under hydrothermal crystallization and then calcining it at 400 °C for the formation of the TiO2 anatase phase. The structural and textural features of the obtained materials were determined by various physico-chemical techniques such as thermogravimetric analysis, X-ray diffraction, scanning electronic microscopy, nitrogen sorption at 77 K, energy dispersive X-ray analysis and ultraviolet–visible spectrometry. The DRX results showed that calcination at 400 °C of the mixture between the calcined SAPO-34 and TiO2 gel led to the collapse of the original framework of zeolite, but formed the anatase TiO2 in a nano-spherical morphology; however, the use of as-synthesized SAPO-34 supports provides a mixture phase between SAPO-34 and TiO2 anatase after calcination. The photocatalytic properties of the SAPO-34/TiO2 and TiO2-type materials were tested for the removal of methylene blue (MB) dye. The MB degradation proved to increase as a function of contact time, catalyst mass and the initial concentration of MB.The authors thank Generalitat Valenciana (PROMETEOII/2014/010) for financial support

OPTASSIST: A RELATIONAL DATA WAREHOUSE OPTIMIZATION ADVISOR

Data warehouses store large amounts of data usually accessed by complex decision making queries with many selection, join and aggregation operations. To optimize the performance of the data warehouse, the administrator has to make a physical design. During physical designphase, the Data Warehouse Administrator has to select some optimization techniques to speed up queries. He must make many choices as optimization techniques to perform,their selection algorithms, parametersof these algorithms and the attributes and tables used by some of these techniques. We describe in this paper the nature of the difficulties encountered by the administrator during physical design. We subsequently present a tool which helps the administrator to make the right choicesfor optimization. We demonstrate the interactive use of this tool using a relational data warehouse created and populated from the APB-1 Benchmark

Study of the Molecular Biodiversity of the Saharan Bread Wheat in Algeria

Climate change has significantly affected wheat yield. Many studies have suggested that rising temperatures could be harmful to cereals around the world. Thus, the valorization of the desert wheat resources is essential to improve the resistance of this species to climate change. In this context, twenty-eight different local Saharan bread wheat (Triticumaestivum L.) genotypes were described using ten preselected SSR markers. The tested SSRs produced a total number of 20 alleles with an allelic size ranged from 100 pb (WMC261) to 400 pb (WMC257). The allele frequency varied from 0.1 for the allele 230 pb (WMC156) to 1 for the alleles 187 pb, 310 pb (WMC97, WMC168). Likewise, the PIC values ranged from 0 (WMC97, WMC168) to 0.5 (WMC327, WMC233), with an average of 0.34 and the observed heterozygosity (Ho) from 0 to 0.88, with an average of 0.55. The molecular variance (AMOVA) revealed the highest level of intra-population differentiation of local Saharan bread wheat (97%) and the statistical geometric distributions based on PCoA, NJ method and structure analysis confirmed the existence of four major classes of bread wheat. These results substantiate the previous researches based on the morphological markers and contribute for the first time in Algeria to create the genetic fingerprint of the Saharan bread wheat resources and to valorize their drought resistance potential through breeding programs

Interoperability framework for supporting information-based assistance in the factory

The aim of this paper is to propose new interoperability solution, based on Info-Engine framework and web services technology to support data exchange and extraction from PLM system, specially the Windchill tool. This solution will be implemented as a connector module of more generic framework, named Digital Factory Assistant (DFA). The DFA framework aims to provide factory workers by a set of knowledge and information based decision support to improve their activity performance

Sorting improves word-aligned bitmap indexes

Bitmap indexes must be compressed to reduce input/output costs and minimize CPU usage. To accelerate logical operations (AND, OR, XOR) over bitmaps, we use techniques based on run-length encoding (RLE), such as Word-Aligned Hybrid (WAH) compression. These techniques are sensitive to the order of the rows: a simple lexicographical sort can divide the index size by 9 and make indexes several times faster. We investigate row-reordering heuristics. Simply permuting the columns of the table can increase the sorting efficiency by 40%. Secondary contributions include efficient algorithms to construct and aggregate bitmaps. The effect of word length is also reviewed by constructing 16-bit, 32-bit and 64-bit indexes. Using 64-bit CPUs, we find that 64-bit indexes are slightly faster than 32-bit indexes despite being nearly twice as large

Impact of credibility on opinion analysis in social media

© 2018 IOS Press. All rights reserved. In conjunction with the rapid growth and adoption of social media, people are more and more willing to share their personal experiences and opinions about products and/or services with the community. Opinions could be the basis of developing systems that would advise future users on how to proceed with any purchase without risking any disappointment. Unfortunately, opinions are not always genuine due to for instance, biased users as well as mixed feedback coming from the same users (i.e., multi-identity). This paper presents an approach for opinion analysis using credibility as a decisive criterion for supporting future users make sound decisions. The effectiveness of this approach has been tested using opinions posted on Twitter

Databases and Information Systems in the AI Era: Contributions from ADBIS, TPDL and EDA 2020 Workshops and Doctoral Consortium

Research on database and information technologies has been rapidly evolving over the last couple of years. This evolution was lead by three major forces: Big Data, AI and Connected World that open the door to innovative research directions and challenges, yet exploiting four main areas: (i) computational and storage resource modeling and organization; (ii) new programming models, (iii) processing power and (iv) new applications that emerge related to health, environment, education, Cultural Heritage, Banking, etc. The 24th East-European Conference on Advances in Databases and Information Systems (ADBIS 2020), the 24th International Conference on Theory and Practice of Digital Libraries (TPDL 2020) and the 16th Workshop on Business Intelligence and Big Data (EDA 2020), held during August 25–27, 2020, at Lyon, France, and associated satellite events aimed at covering some emerging issues related to database and information system research in these areas. The aim of this paper is to present such events, their motivations, and topics of interest, as well as briefly outline the papers selected for presentations. The selected papers will then be included in the remainder of this volume

Data Warehousing Design and Advanced Engineering Applications: Methods for Complex Construction

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