Progettazione ed implementazione di un recommendation system di articoli scientifici basato su Apache Mahout

Il focus di questo elaborato è sui sistemi di recommendations e le relative caratteristiche. L'utilizzo di questi meccanism è sempre più forte e presente nel mondo del web, con un parallelo sviluppo di soluzioni sempre più accurate ed efficienti. Tra tutti gli approcci esistenti, si è deciso di prendere in esame quello affrontato in Apache Mahout. Questa libreria open source implementa il collaborative-filtering, basando il processo di recommendation sulle preferenze espresse dagli utenti riguardo ifferenti oggetti. Grazie ad Apache Mahout e ai principi base delle varie tipologie di recommendationè stato possibile realizzare un applicativo web che permette di produrre delle recommendations nell'ambito delle pubblicazioni scientifiche, selezionando quegli articoli che hanno un maggiore similarità con quelli pubblicati dall'utente corrente. La realizzazione di questo progetto ha portato alla definizione di un sistema ibrido. Infatti l'approccio alla recommendation di Apache Mahout non è completamente adattabile a questa situazione, per questo motivo le sue componenti sono state estese e modellate per il caso di studio. Siè cercato quindi di combinare il collaborative filtering e il content-based in un unico approccio. Di Apache Mahout si è mantenuto l'algoritmo attraverso il quale esaminare i dati del data set, tralasciando completamente l'aspetto legato alle preferenze degli utenti, poichè essi non esprimono delle valutazioni sugli articoli. Del content-based si è utilizzata l'idea del confronto tra i titoli delle pubblicazioni. La valutazione di questo applicativo ha portato alla luce diversi limiti, ma anche possibili sviluppi futuri che potrebbero migliorare la qualità delle recommendations, ma soprattuto le prestazioni. Grazie per esempio ad Apache Hadoop sarebbe possibile una computazione distribuita che permetterebbe di elaborare migliaia di dati con dei risultati più che discreti.

Effective Length K-Factors For Flexural Buckling Strengths Of Web Members In Open Web Steel Joists

Open web steel joists are designed in the United States following the governing specification published by the Steel Joist Institute. For compression members in joists, this specification employs an effective length factor, or K-factor, in confirming their adequacy. In most cases, these K-factors have been conservatively assumed equal to 1.0 for compression web members, regardless of the fact that intuition and limited experimental work indicate that smaller values could be justified. Given that smaller K-factors could result in more economical designs without a loss in safety, the research presented in this thesis aims to suggest procedures for obtaining more rational values. Three different methods for computing in-plane and out-of-plane K-factors are investigated, including (1) a hand calculation method based on the use of alignment charts, (2) computational critical load (eigenvalue) analyses using uniformly distributed loads, and (3) computational analyses using a compressive strain approach. The latter method is novel and allows for computing the individual buckling load of a specific member within a system, such as a joist. Four different joist configurations are investigated, including an 18K3, 28K10, and two variations of a 32LH06. Based on these methods and the very limited number of joists studied, it appears promising that in-plane and out-of-plane K-factors of 0.75 and 0.85, respectively, could be used in computing the flexural buckling strength of web members in routine steel joist design. Recommendations for future work, which include systematically investigating a wider range of joist configurations and connection restraint, are provided.

THE EFFECTS OF WEB-BASED TECHNOLOGICAL RESOURCES IN A RURAL SCIENCE CLASSROOM

Today’s technology is evolving at an exponential rate. Everyday technology is finding more inroads into our education system. This study seeks to determine if having access to technology, including iPad tablets and a teacher's physical science webpage resources (videos, PowerPoint® presentations, and audio podcasts), assists ninth grade high school students in attaining greater comprehension and improved scientific literacy. Comprehension of the science concepts was measured by comparing current student pretest and post test scores on a teacher-written assessment. The current student post test scores were compared with prior classes’ (2010-2011 and 2009-2010) to determine if there was a difference in outcomes between the technology interventions and traditional instruction. Students entered responses to a technology survey that measured intervention usage and their perception of helpfulness of each intervention. The current year class’ mean composite scores, between the pretest and post test increased by 6.9 points (32.5%). Student composite scores also demonstrated that the interventions were successful in helping a majority of students (64.7%) attain the curriculum goals. The interventions were also successful in increasing student scientific literacy by meeting all of Bloom's cognitive levels that were assessed. When compared with prior 2010-2011 and 2009-2010 classes, the current class received a higher mean post test score indicating a positive effect of the use of technological interventions. The survey showed a majority of students utilized at least some of the technology interventions and perceived them as helpful, especially the videos and PowerPoint® presentations.

Integrating structured and unstructured data in a business-intelligence-system

The recent liberalization of the German energy market has forced the energy industry to develop and install new information systems to support agents on the energy trading floors in their analytical tasks. Besides classical approaches of building a data warehouse giving insight into the time series to understand market and pricing mechanisms, it is crucial to provide a variety of external data from the web. Weather information as well as political news or market rumors are relevant to give the appropriate interpretation to the variables of a volatile energy market. Starting from a multidimensional data model and a collection of buy and sell transactions a data warehouse is built that gives analytical support to the agents. Following the idea of web farming we harvest the web, match the external information sources after a filtering and evaluation process to the data warehouse objects, and present this qualified information on a user interface where market values are correlated with those external sources over the time axis.

Autorenwerkzeuge für digitale, multimediale und interaktive Lernbausteine im Web 2.0

Die vorliegende Forschungsarbeit siedelt sich im Dreieck der Erziehungswissenschaften, der Informatik und der Schulpraxis an und besitzt somit einen starken interdisziplinären Charakter. Aus Sicht der Erziehungswissenschaften handelt es sich um ein Forschungsprojekt aus den Bereichen E-Learning und Multimedia Learning und der Fragestellung nach geeigneten Informatiksystemen für die Herstellung und den Austausch von digitalen, multimedialen und interaktiven Lernbausteinen. Dazu wurden zunächst methodisch-didaktische Vorteile digitaler Lerninhalte gegenüber klassischen Medien wie Buch und Papier zusammengetragen und mögliche Potentiale im Zusammenhang mit neuen Web 2.0-Technologien aufgezeigt. Darauf aufbauend wurde für existierende Autorenwerkzeuge zur Herstellung digitaler Lernbausteine und bestehende Austauschplattformen analysiert, inwieweit diese bereits Web 2.0-Technologien unterstützen und nutzen. Aus Sicht der Informatik ergab sich aus der Analyse bestehender Systeme ein Anforderungsprofil für ein neues Autorenwerkzeug und eine neue Austauschplattform für digitale Lernbausteine. Das neue System wurde nach dem Ansatz des Design Science Research in einem iterativen Entwicklungsprozess in Form der Webapplikation LearningApps.org realisiert und stetig mit Lehrpersonen aus der Schulpraxis evaluiert. Bei der Entwicklung kamen aktuelle Web-Technologien zur Anwendung. Das Ergebnis der Forschungsarbeit ist ein produktives Informatiksystem, welches bereits von tausenden Nutzern in verschiedenen Ländern sowohl in Schulen als auch in der Wirtschaft eingesetzt wird. In einer empirischen Studie konnte das mit der Systementwicklung angestrebte Ziel, die Herstellung und den Austausch von digitalen Lernbausteinen zu vereinfachen, bestätigt werden. Aus Sicht der Schulpraxis liefert LearningApps.org einen Beitrag zur Methodenvielfalt und zur Nutzung von ICT im Unterricht. Die Ausrichtung des Werkzeugs auf mobile Endgeräte und 1:1-Computing entspricht dem allgemeinen Trend im Bildungswesen. Durch die Verknüpfung des Werkzeugs mit aktuellen Software-Entwicklungen zur Herstellung von digitalen Schulbüchern werden auch Lehrmittelverlage als Zielgruppe angesprochen.

Key Aspects Affecting Students’ Perception Regarding the Instructional Quality of Online and Web Based Courses

This study assessed the perceptions of college students regarding the instructional quality of online and web based courses via a content management system. [See PDF for complete abstract]

A Web Services architecture for UMLS Knowledge Sources.

A web service is a collection of industry standards to enable reusability of services and interoperability of heterogeneous applications. The UMLS Knowledge Source (UMLSKS) Server provides remote access to the UMLSKS and related resources. We propose a Web Services Architecture that encapsulates UMLSKS-API and makes it available in distributed and heterogeneous environments. This is the first step towards intelligent and automatic UMLS services discovery and invocation by computer systems in distributed environments such as web.

Development, implementation, and evaluation of a structured reporting web tool for abdominal aortic aneurysms

BACKGROUND The majority of radiological reports are lacking a standard structure. Even within a specialized area of radiology, each report has its individual structure with regards to details and order, often containing too much of non-relevant information the referring physician is not interested in. For gathering relevant clinical key parameters in an efficient way or to support long-term therapy monitoring, structured reporting might be advantageous. OBJECTIVE Despite of new technologies in medical information systems, medical reporting is still not dynamic. To improve the quality of communication in radiology reports, a new structured reporting system was developed for abdominal aortic aneurysms (AAA), intended to enhance professional communication by providing the pertinent clinical information in a predefined standard. METHODS Actual state analysis was performed within the departments of radiology and vascular surgery by developing a Technology Acceptance Model. The SWOT (strengths, weaknesses, opportunities, and threats) analysis focused on optimization of the radiology reporting of patients with AAA. Definition of clinical parameters was achieved by interviewing experienced clinicians in radiology and vascular surgery. For evaluation, a focus group (4 radiologists) looked at the reports of 16 patients. The usability and reliability of the method was validated in a real-world test environment in the field of radiology. RESULTS A Web-based application for radiological "structured reporting" (SR) was successfully standardized for AAA. Its organization comprises three main categories: characteristics of pathology and adjacent anatomy, measurements, and additional findings. Using different graphical widgets (eg, drop-down menus) in each category facilitate predefined data entries. Measurement parameters shown in a diagram can be defined for clinical monitoring and be adducted for quick adjudications. Figures for optional use to guide and standardize the reporting are embedded. Analysis of variance shows decreased average time required with SR to obtain a radiological report compared to free-text reporting (P=.0001). Questionnaire responses confirm a high acceptance rate by the user. CONCLUSIONS The new SR system may support efficient radiological reporting for initial diagnosis and follow-up for AAA. Perceived advantages of our SR platform are ease of use, which may lead to more accurate decision support. The new system is open to communicate not only with clinical partners but also with Radiology Information and Hospital Information Systems.

Concepts of Bitemporal Database Theory and the Evolution of Web-Documents

A vast amount of temporal information is provided on the Web. Even though many facts expressed in documents are time-related, the temporal properties of Web presentations have not received much attention. In database research, temporal databases have become a mainstream topic in recent years. In Web documents, temporal data may exist as meta data in the header and as user-directed data in the body of a document. Whereas temporal data can easily be identified in the semi-structured meta data, it is more difficult to determine temporal data and its role in the body. We propose procedures for maintaining temporal integrity of Web pages and outline different approaches of applying bitemporal data concepts for Web documents. In particular, we regard desirable functionalities of Web repositories and other Web-related tools that may support the Webmasters in managing the temporal data of their Web documents. Some properties of a prototype environment are described.

Experiences with a voluntary surveillance system for early detection of equine diseases in Switzerland

Clinical observations made by practitioners and reported using web- and mobile-based technologies may benefit disease surveillance by improving the timeliness of outbreak detection. Equinella is a voluntary electronic reporting and information system established for the early detection of infectious equine diseases in Switzerland. Sentinel veterinary practitioners have been able to report cases of non-notifiable diseases and clinical symptoms to an internet-based platform since November 2013. Telephone interviews were carried out during the first year to understand the motivating and constraining factors affecting voluntary reporting and the use of mobile devices in a sentinel network. We found that non-monetary incentives attract sentinel practitioners; however, insufficient understanding of the reporting system and of its relevance, as well as concerns over the electronic dissemination of health data were identified as potential challenges to sustainable reporting. Many practitioners are not yet aware of the advantages of mobile-based surveillance and may require some time to become accustomed to novel reporting methods. Finally, our study highlights the need for continued information feedback loops within voluntary sentinel networks.

Federally regulated institutional review boards: The aspects of a "model" IRB---Is the current system in need of a tune up or complete overhaul?

Institutional Review Boards (IRBs) are the primary gatekeepers for the protection of ethical standards of federally regulated research on human subjects in this country. This paper focuses on what general, broad measures that may be instituted or enhanced to exemplify a "model IRB". This is done by examining the current regulatory standards of federally regulated IRBs, not private or commercial boards, and how many of those standards have been found either inadequate or not generally understood or followed. The analysis includes suggestions on how to bring about changes in order to make the IRB process more efficient, less subject to litigation, and create standardized educational protocols for members. The paper also considers how to include better oversight for multi-center research, increased centralization of IRBs, utilization of Data Safety Monitoring Boards when necessary, payment for research protocol review, voluntary accreditation, and the institution of evaluation/quality assurance programs. ^ This is a policy study utilizing secondary analysis of publicly available data. Therefore, the research for this paper focuses on scholarly medical/legal journals, web information from the Department of Health and Human Services, Federal Drug Administration, and the Office of the Inspector General, Accreditation Programs, law review articles, and current regulations applicable to the relevant portions of the paper. ^ Two issues are found to be consistently cited by the literature as major concerns. One is a need for basic, standardized educational requirements across all IRBs and its members, and secondly, much stricter and more informed management of continuing research. There is no federally regulated formal education system currently in place for IRB members, except for certain NIH-based trials. Also, IRBs are not keeping up with research once a study has begun, and although regulated to do so, it does not appear to be a great priority. This is the area most in danger of increased litigation. Other issues such as voluntary accreditation and outcomes evaluation are slowing gaining steam as the processes are becoming more available and more sought after, such as JCAHO accrediting of hospitals. ^ Adopting the principles discussed in this paper should promote better use of a local IRBs time, money, and expertise for protecting the vulnerable population in their care. Without further improvements to the system, there is concern that private and commercial IRBs will attempt to create a monopoly on much of the clinical research in the future as they are not as heavily regulated and can therefore offer companies quicker and more convenient reviews. IRBs need to consider the advantages of charging for their unique and important services as a cost of doing business. More importantly, there must be a minimum standard of education for all IRB members in the area of the ethical standards of human research and a greater emphasis placed on the follow-up of ongoing research as this is the most critical time for study participants and may soon lead to the largest area for litigation. Additionally, there should be a centralized IRB for multi-site trials or a study website with important information affecting the trial in real time. There needs to be development of standards and metrics to assess the performance of the IRBs for quality assurance and outcome evaluations. The boards should not be content to run the business of human subjects' research without determining how well that function is actually being carried out. It is important that federally regulated IRBs provide excellence in human research and promote those values most important to the public at large.^

Visibilidad de los repositorios institucionales argentinos en la Web : Indicadores y buenas prácticas

Se aborda el estudio de la evaluación de los repositorios institucionales desde una perspectiva cibermétrica. En primer lugar se presenta la sede online universitaria como un sistema complejo y rico documentalmente, analizable desde un punto de vista tanto sistémico como cuantitativo. Tras ello, se sitúa el repositorio institucional como una sede independiente alojada dentro de la sede académica, con unos objetivos y características propios, y que pueden ser igualmente analizados desde un punto de vista cibermétrico. A continuación se exponen los indicadores cibermétricos más importantes utilizados en el análisis de repositorios institucionales (aplicando su uso a SeDICI, repositorio institucional de la Universidad Nacional de la Plata). Se finaliza con la presentación del Ranking Web de Repositorios del Mundo, en el que se aplican diversos indicadores cibermétricos, analizando la presencia de los repositorios institucionales argentinos en el mismo.

Arquitectura de sitios Web de bibliotecas universitarias : El sistema de bibliotecas de la Universidad Nacional de La Plata, Argentina

Este trabajo descriptivo exploratorio se propone analizar la arquitectura de información (AI) de sitios Web de bibliotecas de la Universidad Nacional de La Plata (UNLP), Argentina. Se analizaron 17 bibliotecas y se aplicó una grilla para recabar 10 aspectos relevantes. Los resultados fueron: 1. Ubicación del sitio Web de la biblioteca: 9 sitios incluidos en la página principal de la facultad. 2. Etiquetado de contenidos: terminología simple, sin jergas; no hay homogeneidad entre las bibliotecas. 3. Capacidad de búsqueda: 62 por ciento positiva, 38 por ciento negativa. 4. Sistema de búsqueda: simple 43 por ciento, compleja 10 por ciento, con ayudas 10 por ciento, ninguno 38 por ciento. 5. Sistemas de navegación: globales 5 por ciento, jerárquicos 79 por ciento, locales 5 por ciento, ninguno 11 por ciento. 6. Herramientas de navegación: barras 16 por ciento, frames o marcos 30 por ciento, índices 2 por ciento, mapas de sitio 7 por ciento, menús horizontales 9 por ciento, menús verticales 35 por ciento. 7. Sindicación de contenidos RSS: 3 sitios. 8. Otros servicios: chat 7 por ciento, descarga de documentos 16 por ciento, envío de formularios 14 por ciento, instructivos 21 por ciento, links a otras páginas 23 por ciento, tutoriales 5 por ciento, otros 14 por ciento. 9. Accesibilidad Web: 1 sitio. 10. Otras observaciones: ninguna. Se concluye que el desarrollo de los sitios es dispar y se recomienda considerar pautas de AI como parte de la cooperación en la red de bibliotecas de la UNLP