Data mining techniques for portal participants profiling

Recently, a large number of virtual learning communities appeared in the Web, however,keeping them up occurs to be problematic and information accessibility is one of the factors thatmay influence their sustainability. This feature may be achieved by dividing users into groupsaccording to their information needs and by adapting properly the portal contents. In the paperapplication for data mining algorithms, for finding patterns together with different groups ofpreferences is considered. We base our research on the data contained in log files. Combination ofsequential pattern mining and clustering techniques is proposed. We describe the data preparationprocess. The experiments conducted for real data log files are discussed

Automatic Keyphrase Extraction

Increasing number of documents in the Web caused the growth of needs for tools supporting automatic search and classification of texts. Keywords are one of characteristic features of documents that may be used as criteria in automatic document management. In the paper we describe the technique for automatic keyphrase extraction based on the KEA algorithm [1]. The main modifications consist in changes in the stemming method and simplification of the discretization technique. Besides, in the presented algorithm the keyphrase list may contain proper names, and the candidate phrase list may contain number sequences. We describe experiments, that were done on the set of English language documents available in the Internet and that allow for optimization of extraction parameters. The comparison of the efficiency of the algorithm with the KEA technique is presented

Assessment of various diagnostic methods of ureaplasma respiratory tract infections in newborns

We compared three methods used microbial culturing for detection of ureaplasmas in endotracheal aspirate from 500 prematurely born neonates with respiratory disturbances: BioMerieux test, PCR and microbial culturing. Ureaplasmas were detected in respiratory tracts of 79 (16%) newborns. Correlation of the results of culture with those obtained with the BioMerieux kit, culture with PCR and BioMerieux kit with PCR was 97%, 89% and 90%, respectively. Sensitivity and specificity of PCR in comparison with culture was 86% and 98%, respectively, and of the BioMerieux kit 96% and 98%. PCR can be recommended in rapid diagnostics of respiratory infections in newborns suffering from respiratory disorders. It allows the detection of ureaplasmas in case of parallel infections and identification of their species

Evaluation of vertical transmission of two species of Ureaplasmas in term newborns without respiratory disorders – a preliminary study

Abstract Pregnancy promotes ureaplasma vaginal colonization. This creates the possibility of vertical transmission of these organisms to the child. These microorganisms can cause complications during pregnancy and poor condition of newborn. Objectives: Objectives of this study were to analyze the vertical transmission of different species of ureaplasmas in term newborns without respiratory distress. Materials and Methods: The study included 50 mothers and 50 of their newborn children. Swabs were obtained from swabs of the cervix in women and tracheal aspirates from neonates. The presence of ureaplasmas was confirmed by culture and PCR. Ureaplasmas species identification was performed using PCR. Results: infection of ureaplasmas was found in 21 women (42%). Predominant species was U.parvum, which was found in 18 women. In 3 patients only the presence of U.urealyticum was confirmed. Ureaplasma infection in mother and her newborn baby was confirmed in 8 (17.4%) mother-child pairs, including 6 of these cases showing the presence of U.parvum and 2 U.urealyticum. The incidence of vertical transmission of ureaplasma infection was assessed at 33% for U.parvum and 67% for U.urealyticum, and the total for both species at 38%. It should be noted that in the group of 18 women infected with U.parvum, in 12 cases there was no transmission of infection to the child. However, in 3 women infected with U.urealyticum 2 cases of transmission from mother to child were observed (67%). Although the group infected with U.urealyticum accounted for only 3 women, our preliminary observations may suggest that this species is probably more likely to be transferred from mother to child. Conclusions: Infection with U.urealyticum may be more frequently transferred from the genital tract of mother to child

Eksploracja danych w modelowaniu użytkowników edukacyjnych systemów internetowych

[...] Celem monografii jest prezentacja zagadnień dotyczących zastosowania algorytmów eksploracji danych do modelowania użytkowników na potrzeby edukacyjnych systemów internetowych. W rozważanej dziedzinie eksploracja danych służy do przekształcania surowych danych w wiedzę, która umożliwi poznanie cech charakterystycznych studentów bądź predykcję ich zachowania w celu właściwego dopasowania systemów wspomagających nauczanie do ich potrzeb, jak również zwiększenia efektywności procesu dydaktycznego. W przeciwieństwie do większości zastosowań, gdzie wymagania dotyczące własności algorytmów eksploracji danych są głównie związane z ich wydajnością i elastycznością, w systemach nauczania na odległość nacisk kładzie się na prostotę stosowanej techniki, gdyż edukatorzy powinni rozumieć metody, których używają. W monografii rozważono podejście oparte na budowaniu grup studentów i ich modeli oraz na wykorzystaniu do tego celu technik eksploracji danych. Szczególną uwagę zwrócono na zastosowanie klasyfikacji bez nadzoru do tworzenia grup studentów.[...

Zastosowanie technik eksploracji danych do budowania grup studenckich

Finding student groups of similar preferences enables to adjust e-learning systems according to their needs. In the paper, it is compared usage of different data mining techniques for creating learners’ groups. It is considered application of supervised and unsupervised classification as well as frequent pattern mining.Znalezienie grup studentów o podobnych preferencjach umożliwi dopasowanie do ich potrzeb systemu nauczania na odległość. Celem pracy jest porównanie różnych technik eksploracji danych do budowania grup. Rozważa się zastosowanie klasyfikacji bez nadzoru oraz po nadzorem, jak również wykrywania wzorców sekwencji