How Scale Affects Structure in Java Programs

Many internal software metrics and external quality attributes of Java programs correlate strongly with program size. This knowledge has been used pervasively in quantitative studies of software through practices such as normalization on size metrics. This paper reports size-related super- and sublinear effects that have not been known before. Findings obtained on a very large collection of Java programs -- 30,911 projects hosted at Google Code as of Summer 2011 -- unveils how certain characteristics of programs vary disproportionately with program size, sometimes even non-monotonically. Many of the specific parameters of nonlinear relations are reported. This result gives further insights for the differences of "programming in the small" vs. "programming in the large." The reported findings carry important consequences for OO software metrics, and software research in general: metrics that have been known to correlate with size can now be properly normalized so that all the information that is left in them is size-independent.Comment: ACM Conference on Object-Oriented Programming, Systems, Languages and Applications (OOPSLA), October 2015. (Preprint

SourcererCC: Scaling Code Clone Detection to Big Code

Despite a decade of active research, there is a marked lack in clone detectors that scale to very large repositories of source code, in particular for detecting near-miss clones where significant editing activities may take place in the cloned code. We present SourcererCC, a token-based clone detector that targets three clone types, and exploits an index to achieve scalability to large inter-project repositories using a standard workstation. SourcererCC uses an optimized inverted-index to quickly query the potential clones of a given code block. Filtering heuristics based on token ordering are used to significantly reduce the size of the index, the number of code-block comparisons needed to detect the clones, as well as the number of required token-comparisons needed to judge a potential clone. We evaluate the scalability, execution time, recall and precision of SourcererCC, and compare it to four publicly available and state-of-the-art tools. To measure recall, we use two recent benchmarks, (1) a large benchmark of real clones, BigCloneBench, and (2) a Mutation/Injection-based framework of thousands of fine-grained artificial clones. We find SourcererCC has both high recall and precision, and is able to scale to a large inter-project repository (250MLOC) using a standard workstation.Comment: Accepted for publication at ICSE'16 (preprint, unrevised

PRT simulation in an immersive virtual world

Immersive virtual world environments, such as Second LifeTM (SL), have the potential to dramatically improve the process of analyzing usability within technically correct system simulations, long before the system is built. We report our findings with the SL simulation of a Personal Rapid Transit (PRT) system. The SL model and simulation were done according to the original technical specifications. In interacting with this simulation, the system designers were able to identify several usability issues that would have gone unnoticed in a non-immersive simulation environment. Namely: (1) a problem with the design of the offramp to the station; (2) further requirements for the design of the top of the vehicles, so that the suspended track is out of direct sight of the people inside; (3) further safety requirements for dealing with unexpected obstacles along the path. While all of these issues would have been identified upon deployment of the physical prototype, the contribution of our work is to show how usability issues like these can now be identified much earlier, using simulations in a virtual world. Copyright © 2008 ICST

Comparing "pick and place" task in spatial Augmented Reality versus non-immersive Virtual Reality for rehabilitation setting.

Introducing computer games to the rehabilitation market led to development of numerous Virtual Reality (VR) training applications. Although VR has provided tremendous benefit to the patients and caregivers, it has inherent limitations, some of which might be solved by replacing it with Augmented Reality (AR). The task of pick-and-place, which is part of many activities of daily living (ADL's), is one of the major affected functions stroke patients mainly expect to recover. We developed an exercise consisting of moving an object between various points, following a flash light that indicates the next target. The results show superior performance of subjects in spatial AR versus non-immersive VR setting. This could be due to the extraneous hand-eye coordination which exists in VR whereas it is eliminated in spatial AR

A qualitative study about college students' attitudes, knowledge and perceptions regarding sugar intake

Excessive sugar intake has been associated with multiple health conditions (e.g., higher risk for non-communicable diseases). Hence, health organizations have issued guidelines defining the maximum daily intake of free or added sugars. However, data from several countries suggests that these guidelines are rarely met, particularly by young adults. For example, almost half of Portuguese adolescents and young adults exceed the recommended sugar intake. In this work, we aim to further explore college students' attitudes, knowledge, and perceptions about sugar intake, as well as about sugar intake guidelines. A thematic analysis on data from five focus groups (N = 40) indicated that participants reported difficulty in the comprehension of added/free sugars definition and sugar intake recommendations. Overall, attitudes toward sugar were ambivalent. Sugar was simultaneously perceived as pleasurable and needed, but also as addictive and harmful. Although aware of the potential negative health outcomes associated with excessive sugar intake, most participants did not perceive being at risk due to their youth, exercise habits, or type of diet. The few concerns expressed were mostly associated with the negative impact of high sugar intake on body image (e.g., weight gain). The main barriers to reducing sugar intake identified were environmental (e.g., time restrictions, food available at the university). Still, participants could identify several individual strategies to effectively regulate sugar intake. By identifying knowledge gaps and sources of bias related to sugar consumption, our findings are useful to inform future interventions aiming to address the problem of high sugar intake among university students.info:eu-repo/semantics/acceptedVersio