1,720,978 research outputs found
Automatic repair of timestamp comparisons
Full text linkAutomated program repair has the potential to reduce the developers’ effort to fix errors in their code. In particular, modern programming languages, such as Java, C, and C#, represent time as integer variables that suffer from integer overflow, introducing subtle errors that are hard to discover and repair. Recent researches on automated program repair rely on test cases to discover failures to correct, making them suitable only for regression errors. We propose a new strategy to automatically repair programs that suffer from timestamp overflows that are manifested in comparison expressions. It unifies the benefits of static analysis and automatic program repair avoiding to depend on testing to identify and correct defected code. Our approach performs an abstract analysis over the time domain of a program using a Time Type System to identify the problematic comparison expressions. The repairing strategy rewrites the timestamp comparisons exploiting the binary representation of machine numbers to correct the code. We have validated the applicability of our approach with 20 open source Java projects. The results show that it is able to correctly repair all 246 identified errors. Furthermore, several patches for three open source projects have been acknowledged and accepted by their developers
Modeling time in Java programs for automatic error detection
Full text linkModern programming languages, such as Java, represent time as integer variables, called timestamps. Timestamps allow developers to tacitly model incorrect time values resulting in a program failure because any negative value or every positive value is not necessarily a valid time representation. Current approaches to automatically detect errors in programs, such as Randoop and FindBugs, cannot detect such errors because they treat timestamps as normal integer variables and test them with random values verifying if the program throws an exception. In this paper, we present an approach that considers the time semantics of the Java language to systematically detect time related errors in Java programs. With the formal time semantics, our approach determines which integer variables handle time and which statements use or alter their values. Based on this information, it translates these statements into an SMT model that is passed to an SMT solver. The solver formally verifies the correctness of the model and reports the violations of time properties in that program. For the evaluation, we have implemented our approach in a prototype tool and applied it to the source code of 20 Java open source projects. The results show that our approach is scalable and it is capable of detecting time errors precisely enough allowing its usability in real-world applications
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
Challenges in modelling applications for safe and resilient digital twins
No full textDigital twin-based modern smart city infrastructures are evolving into intelligent and distributed systems of autonomous entities operating in a dynamic cyber-physical environment to offer real-time and critical services. These services are typically implemented as software applications in various application domains, e.g., healthcare, cooperative robotic systems, and autonomous vehicles. However, to assure continued safe operations of the critical services with strict real-time requirements even when the service is under attack is an extremely challenging task mainly because the underlying operating environment for such applications is highly volatile yet distributed. To this end, first, we classify (as we call it) timed resilience requirements into computational and communication resilience and then discuss key challenges that hinder the modeling of such requirements to help develop rigorous distributed applications for real-time resilient autonomous systems. Finally, we demonstrate our vision to handle these challenges by introducing by-design and by-response approaches that consider security as a prerequisite of the safety and resilience of autonomous systems
Towards practical and formal security risk analysis of IoT (Internet of Things) applications
No full textWe present the initial results of developing a security risk analyzer for Internet of Things (IoT) applications that analyses both evitable and inevitable yet known and unknown cyber-attacks and as a result produces the adversarial strategies (multi-stages of attack) that can compromise the application. Our risk analyzer is rigorous and qualitative, performing technical analysis, as well as quantitative yet useful, identifying sub-attacks and their quantitative risks. In contrast, conventional security risk analyzers either provide too specific risk assessment or provide a too generic risk assessment of a given application. Such analyzers are typically not practical against constantly changing attacks of the variable extent and complex modern IoT applications. We demonstrate the usability of our methodology through the detection of an example attack model from a real-world incident in real-time
Middle Term Outcomes of Surgical Treatment of Developmental Dysplasia of the Hip in the Department of Orthopedic Surgery
No full textThe thesis on Developmental Dysplasia of the Hip (DDH) provides an in-depth analysis of the multifactorial causes and the crucial role of early diagnosis using clinical and radiological methods, particularly ultrasound. Highlighting the specific approach in Hungary, the study evaluates the outcomes of various treatments at the Department of Orthopedics in Debrecen. The research, involving 39 hips, demonstrates that initial closed reductions yield the best outcomes, with 100% satisfactory results and no cases of avascular necrosis (AVN). Conversely, the need for osteotomies correlates with worse outcomes and a higher incidence of AVN. The study emphasizes the importance of tension-free reductions to minimize complications, aligning with existing literature. Overall, this work underscores the complexity of DDH treatment and the necessity for individualized approaches to optimize patient outcomes.egységes, osztatlanáltalános orvosango
Urban Climate in Flux Investigating the Climatic Influence of Solar Panels and Agriculture in Cityscapes
No full textThis thesis investigates into the impacts of solar panels and urban agriculture on the urban climate. It also highlights that how these technologies influence the overall dynamics of urban
climate, environmental stability and energy balance of the atmosphere. There is a rapid change in climate due to rapid urbanization hence cities are in search of innovative ideas to cancel out negative effects these changes bring. These changes can be efficiently addressed by the use of renewable energy resource which provide clean energy and the introduction of vegetation which have promising effects in terms of mitigating the urban heat and pollution.BSc/BABsc. Earth Science
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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