1,721,048 research outputs found
Studio dell'interazione della "generazione distribuita" con possibili futuri assetti della rete di distribuzione
No full textThe aim of this work is to study the course of the distribution network with connected generators in order to improve the electric service provided by the supplier. In this research we have realized a control system which is able to check carefully the voltage profile and to adjust it by modifying the distributed generation and TAP.
The surplus of energy produced by the generators modifies the level of the node voltage and it can be used to supply other portion of the grid. For this purpose we have analized a type of device which allows the riconfiguration of the network (FACTS).
Anthother step of this work is to study how the dispersed generators could be exploited in order to improve the quality and the continuity of the power supply thus reducing the outage events. We have realized a procedure which allows to locate the portion of the distribution network that can be isolated from the main grid and which is able to self-supply itself for a long time.L’obiettivo di questo lavoro è lo studio del comportamento della rete di distribuzione in presenza di generatori allacciati al fine di migliorare il servizio elettrico fornito dal gestore. La ricerca ha portato alla realizzazione di un sistema di controllo che permette di monitorare il profilo di tensione delle dorsali e di regolare quest’ultimo agendo sia sui generatori dispersi che sul variatore sottocarico.
L’esubero di energia prodotta dai generatori, oltre a modificare il livello di tensione ai nodi, può essere utilizzato per alimentare altre zone della rete di distribuzione dove i carichi allacciati assorbono potenze troppo elevate; perché questo accada sono stati presi in considerazione alcuni dispositivi che permettono la riconfigurazione del sistema elettrico (FACTS).
Un ulteriore sviluppo della ricerca è quello di capire come sfruttare la risorsa dispersa di potenza per fornire agli utenti una continuità del servizio elettrico e, di conseguenza, ridurre i disservizi. A questo proposito è stato realizzato un sistema di calcolo che permette, sotto particolari condizioni, di determinare la più grande porzione di rete in grado di isolarsi dal sistema elettrico e di auto sostenersi per un lungo periodo di tempo
APOGEN: automatic page object generator for web testing
No full textModern web applications are characterized by ultra-rapid development cycles, and web testers tend to pay scant attention to the quality of their automated end-to-end test suites. Indeed, these quickly become hard to maintain, as the application under test evolves. As a result, end-to-end automated test suites are abandoned, despite their great potential for catching regressions. The use of the Page Object pattern has proven to be very effective in end-to-end web testing. Page objects are façade classes abstracting the internals of web pages into high-level business functions that can be invoked by the test cases. By decoupling test code from web page details, web test cases are more readable and maintainable. However, the manual development of such page objects requires substantial coding effort, which is paid off only later, during software evolution. In this paper, we describe a novel approach for the automatic generation of page objects for web applications. Our approach is implemented in the tool Apogen, which automatically derives a testing model by reverse engineering the target web application. It combines clustering and static analysis to identify meaningful page abstractions that are automatically turned into Java page objects for Selenium WebDriver. Our evaluation on an open-source web application shows that our approach is highly promising: Automatically generated page object methods cover most of the application functionalities and result in readable and meaningful code, which can be very useful to support the creation of more maintainable web test suites
Robula+: an algorithm for generating robust XPath locators for web testing
No full textAutomated test scripts are used with success in many web development projects, so as to automatically verify key functionalities of the web application under test, reveal possible regressions and run a large number of tests in short time. However, the adoption of automated web testing brings advantages but also novel problems, among which the test code fragility problem. During the evolution of the web application, existing test code may easily break and testers have to correct it. In the context of automated DOM-based web testing, one of the major costs for evolving the test code is the manual effort necessary to repair broken web page element locators – lines of source code identifying the web elements (e.g. form fields and buttons) to interact with.
In this work, we present robula+, a novel algorithm able to generate robust XPath-based locators – locators that are likely to work correctly on new releases of the web application. We compared robula+ with several state of the practice/art XPath locator generator tools/algorithms. Results show that XPath locators produced by robula+ are by far the most robust. Indeed, robula+ reduces the locators' fragility on average by 90% w.r.t. absolute locators and by 63% w.r.t. Selenium IDE locator
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
P<scp>esto</scp> : Automated migration of DOM-based Web tests towards the visual approach
No full textTest automation tools are widely adopted for testing complex Web applications. Three generations of tools exist: first, based on screen coordinates; second, based on DOM–based commands; and third, based on visual image recognition. In our previous work, we proposed Pesto, a tool able to migrate second‐generation Selenium WebDriver test suites towards third‐generation Sikuli ones. In this work, we extend Pesto to manage Web elements having (1) complex visual interactions and (2) multiple visual appearances. Pesto relies on aspect‐oriented programming, computer vision, and code transformations. Our new improved tool has been evaluated on two Web test suites developed by an independent tester. Experimental results show that Pesto manages and transforms correctly test suites with Web elements having complex visual interactions and multistate elements. By using Pesto, the migration of existing DOM–based test suites to the visual approach requires a low manual effort, since our approach proved to be very accurate
Three Open Problems in the Context of E2E Web Testing and a Vision: NEONATE
No full textWeb applications are critical assets of our society and thus assuring their quality is of undeniable importance. Despite the advances in software testing, the ever-increasing technological complexity of these applications makes it difficult to prevent errors. In this work, we provide a thorough description of the three open problems hindering web test automation: fragility problem, strong coupling and low cohesion problem, and incompleteness problem. We conjecture that a major breakthrough in test automation is needed, because the problems are closely correlated, and hence need to be attacked together rather than separately. To this aim, we describe NEONATE, a novel integrated testing environment specifically designed to empower the web tester. Our utmost purpose is to make the research community aware of the existence of the three problems and their correlation, so that more research effort can be directed in providing solutions and tools to advance the state of the art of web test automation
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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