An ergonomic study on plate shears, applying physical, physiological and psychophysical methods

An ergonomic evaluation model for hand tools was developed and applied in a project aiming at assessment of work with plate shears. Measurement variables were physical, physiological and psychophysical. They included tool force and opening angle, wrist movements, muscular strain and fatigue, subjective rating of symptoms, and localization of symptoms, in a group of male professional platers. Different hand grips were studied in a series of cutting tasks (4.2 m cutting length). Results showed that working with conventional plate shears is extremely physically demanding. The peak force required was in the range of 26 to 72 per cent of the subjects' maximal hand grip force. There was ample localized muscle fatigue in the forearm. Psychophysical and electrophysiological data agreed with respect to aspects of muscular strain and fatigue. Workers' preferences in the short run seemed to focus on productivity rather than on ergonomic quality. There is a need for development of improved tools, based on formulated requirements.     

Optimizing the execution of XSLT stylesheets for querying transformed XML data

We have to deal with different data formats whenever data formats evolve or data must be integrated from heterogeneous systems. These data when implemented in XML for data exchange cannot be shared freely among applications without data transformation. A common approach to solve this problem is to convert the entire XML data from their source format to the applications’ target formats using the transformations rules specified in XSLT stylesheets. However, in many cases, not all XML data are required to be transformed except for a smaller part described by a user’s query (application). In this paper, we present an approach that optimizes the execution time of an XSLT stylesheet for answering a given XPath query by modifying the XSLT stylesheet in such a way that it would (a) capture only the parts in the XML data that are relevant to the query and (b) process only those XSLT instructions that are relevant to the query. We prove the correctness of our optimization approach, analyze its complexity and present experimental results. The experimental results show that our approach performs the best in terms of execution time, especially when many cost-intensive XSLT instructions can be excluded in the XSLT stylesheet.     

Web-scale provenance reconstruction of implicit information diffusion on social media

Fast, massive, and viral data diffused on social media affects a large share of the online population, and thus, the (prospective) information diffusion mechanisms behind it are of great interest to researchers. The (retrospective) provenance of such data is equally important because it contributes to the understanding of the relevance and trustworthiness of the information. Furthermore, computing provenance in a timely way is crucial for particular use cases and practitioners, such as online journalists that promptly need to assess specific pieces of information. Social media currently provide insufficient mechanisms for provenance tracking, publication and generation, while state-of-the-art on social media research focuses mainly on explicit diffusion mechanisms (like retweets in Twitter or reshares in Facebook).The implicit diffusion mechanisms remain understudied due to the difficulties of being captured and properly understood. From a technical side, the state of the art for provenance reconstruction evaluates small datasets after the fact, sidestepping requirements for scale and speed of current social media data. In this paper, we investigate the mechanisms of implicit information diffusion by computing its fine-grained provenance. We prove that explicit mechanisms are insufficient to capture influence and our analysis unravels a significant part of implicit interactions and influence in social media. Our approach works incrementally and can be scaled up to cover a truly Web-scale scenario like major events. We can process datasets consisting of up to several millions of messages on a single machine at rates that cover bursty behaviour, without compromising result quality. By doing that, we provide to online journalists and social media users in general, fine grained provenance reconstruction which sheds lights on implicit interactions not captured by social media providers. These results are provided in an online fashion which also allows for fast relevance and trustworthiness assessment.     

Giving too much social support: social overload on social networking sites

As the number of messages and social relationships embedded in social networking sites (SNS) increases, the amount of social information demanding a reaction from individuals increases as well. We observe that, as a consequence, SNS users feel they are giving too much social support to other SNS users. Drawing on social support theory (SST), we call this negative association with SNS usage ‘social overload’ and develop a latent variable to measure it. We then identify the theoretical antecedents and consequences of social overload and evaluate the social overload model empirically using interviews with 12 and a survey of 571 Facebook users. The results show that extent of usage, number of friends, subjective social support norms, and type of relationship (online-only vs offline friends) are factors that directly contribute to social overload while age has only an indirect effect. The psychological and behavioral consequences of social overload include feelings of SNS exhaustion by users, low levels of user satisfaction, and a high intention to reduce or even stop using SNS. The resulting theoretical implications for SST and SNS acceptance research are discussed and practical implications for organizations, SNS providers, and SNS users are drawn.     

Socio-technical IS design science research: developing design theory for IS integration management

Design science research is an essential part of IS research since the field should not only try to understand how the world is, but also how to change it. We argue that the aim of IS design science research should be to develop practical knowledge not only for the design of novel information technology (IT), but also for IS governance and management. Whereas at least some methodological support exists for researchers engaged in IT-centric design science research, limited support is available for researchers who want to develop design knowledge and theory for IS governance and management. To overcome this shortcoming, we suggest a socio-technical IS design science research approach. The approach has four main activities: (1) identifying problem situations and desired outcomes, (2) reviewing extant theories, knowledge and data, (3) proposing/refining design theory and knowledge, and (4) testing design theory and knowledge. The applicability and usefulness of the proposed approach is shown by means of a design science research project concerning IS integration management in the context of mergers and acquisitions.