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61.
Laura Hollink Véronique Malaisé Guus Schreiber 《Multimedia Tools and Applications》2010,49(1):235-257
It is common practice in audiovisual archives to disclose documents using metadata from a structured vocabulary or thesaurus.
Many of these thesauri have limited or no structure. The objective of this paper is to find out whether retrieval of audiovisual
resources from a collection indexed with an in-house thesaurus can be improved by enriching the thesaurus structure. We propose
a method to add structure to a thesaurus by anchoring it to an external, semantically richer thesaurus. We investigate the
added value of this enrichment for retrieval purposes. We first anchor the thesaurus to an external resource, WordNet. From
this anchoring we infer relations between pairs of terms in the thesaurus that were previously unrelated. We employ the enriched
thesaurus in a retrieval experiment on a TRECVID 2007 dataset. The results are promising: with simple techniques we are able
to enrich a thesaurus in such a way that it adds to retrieval performance. 相似文献
62.
Giacomo Bucci Laura Carnevali Lorenzo Ridi Enrico Vicario 《International Journal on Software Tools for Technology Transfer (STTT)》2010,12(5):391-403
Oris is a tool for qualitative verification and quantitative evaluation of reactive timed systems, which supports modeling
and analysis of various classes of timed extensions of Petri Nets. As most characterizing features, Oris implements symbolic
state space analysis of preemptive Time Petri Nets, which enable schedulability analysis of real-time systems running under
priority preemptive scheduling; and stochastic Time Petri Nets, which enable an integrated approach to qualitative verification
and quantitative evaluation. In this paper, we present the current version of the tool and we illustrate its application to
two different case studies in the areas of qualitative verification and quantitative evaluation, respectively. 相似文献
63.
64.
Laura H. Ikuma Maury A. Nussbaum Kari L. Babski-Reeves 《International Journal of Industrial Ergonomics》2009,39(5):813-820
Responses to physical and psychosocial exposures can be measured using diverse methods, but their reliability, particularly under multiple exposures, is largely unknown. Five classes of methods were used to assess physiological and subjective responses among 24 participants to four combinations of physical and psychosocial exposures while performing two identical sessions of a simulated overhead manufacturing task. As an exploratory analysis, test–retest reliability was quantified using intraclass correlation coefficients (ICC) and coefficients of variation (CV). Discomfort ratings were reliable under less favorable exposures, and ratings of the psychosocial environment were most reliable under favorable social support. Workload ratings were most reliable with high physical exposure and favorable social support, and task performance was reliable overall. EMG and heart rate had relatively low reliability. Slightly less than half of the variables were considered reliable, but reliability depended on exposure conditions.Relevance to industry: The study provides information on the reliability of commonly used exposure measurement methods. The results can guide the selection of physiological and psychological work outcome measurements in future studies and work evaluations. 相似文献
65.
66.
Manuel Pedro Rodríguez Bolívar Laura Alcaide Muñoz Antonio M. López Hernández 《Information Technology for Development》2016,22(1):36-74
Many countries have implemented changes in public-sector management models, based on the strategic and intensive use of new information and communication technologies. From a critical standpoint, this paper analyzes and characterizes the contributions made by research in the field of e-government, identifying future areas of interest and potentially valuable methodologies. In addition, it compares research efforts focused on developing countries with those concerning developed economies, in order to identify research gaps and possibilities for improvement in the context of e-government research in developing countries. Diverse scientometric approaches are employed in this analysis of papers published by international journals listed in the SSCI index in the fields of Public Administration and of Information Science & Library Science. Our findings reveal the existence of various research gaps and highlight areas that should be addressed in future research, especially in developing countries. Indeed, the research approach to e-government remains immature, focusing on particular cases or dimensions, while little has been done to produce theories or models to clarify and explain the political processes of e-government. In addition, significant differences are found between the impact of scientific output and patterns of scientific production as regards developing and developed countries. 相似文献
67.
Laura Sánchez-González Félix García Francisco Ruiz Mario Piattini 《Software and Systems Modeling》2017,16(3):759-788
Organizations are increasingly concerned about business process model improvement in their efforts to guarantee improved operational efficiency. Quality assurance of business process models should be addressed in the most objective manner, e.g., through the application of measures, but the assessment of measurement results is not a straightforward task and it requires the identification of relevant indicators and threshold values, which are able to distinguish different levels of process model quality. Furthermore, indicators must support the improvements of the models by using suitable guidelines. In this paper, we present a case study to evaluate the BPMIMA framework for BP model improvement. This framework is composed of empirically validated measures related to quality characteristics of the models, a set of indicators with validated thresholds associated with modeling guidelines and a prototype supporting tool. The obtained data suggest that the redesign by applying guidelines driven by the indicator results was successful, as the understandability and modifiability of the models were improved. In addition, the changes in the models according to guidelines were perceived as acceptable by the practitioners who participated in the case study. 相似文献
68.
We investigate the complexity of preorder checking when the specification is a flat finite-state system whereas the implementation is either a non-flat finite-state system or a standard timed automaton. In both cases, we show that simulation checking is Exptime-hard, and for the case of a non-flat implementation, the result holds even if there is no synchronization between the parallel components and their alphabets of actions are pairwise disjoint. Moreover, we show that the considered problems become Pspace-complete when the specification is assumed to be deterministic. Additionally, we establish that comparing a synchronous non-flat system with no hiding and a flat system is Pspace-hard for any relation between trace containment and bisimulation equivalence, even if the flat system is assumed to be fixed. 相似文献
69.
Hadwiger M Laura F Rezk-Salama C Höllt T Geier G Pabel T 《IEEE transactions on visualization and computer graphics》2008,14(6):1507-1514
This paper presents a novel method for interactive exploration of industrial CT volumes such as cast metal parts, with the goal of interactively detecting, classifying, and quantifying features using a visualization-driven approach. The standard approach for defect detection builds on region growing, which requires manually tuning parameters such as target ranges for density and size, variance, as well as the specification of seed points. If the results are not satisfactory, region growing must be performed again with different parameters. In contrast, our method allows interactive exploration of the parameter space, completely separated from region growing in an unattended pre-processing stage. The pre-computed feature volume tracks a feature size curve for each voxel over time, which is identified with the main region growing parameter such as variance. A novel 3D transfer function domain over (density, feature size, time) allows for interactive exploration of feature classes. Features and feature size curves can also be explored individually, which helps with transfer function specification and allows coloring individual features and disabling features resulting from CT artifacts. Based on the classification obtained through exploration, the classified features can be quantified immediately. 相似文献
70.
Interfacing human and computer with wireless body area sensor networks: the WiMoCA solution 总被引:1,自引:0,他引:1
Elisabetta Farella Augusto Pieracci Luca Benini Laura Rocchi Andrea Acquaviva 《Multimedia Tools and Applications》2008,38(3):337-363
Wireless Body Area Sensor Networks (WBASN) are an emerging technology enabling the design of natural human–computer interfaces
(HCI). Automatic recognition of human motion, gestures, and activities is studied in several contexts. For example, mobile
computing technology is being considered as a replacement of traditional input systems. Moreover, body posture and activity
monitoring can be used for entertainment and health-care applications. However, until now, little work has been done to develop
flexible and efficient WBASN solutions suitable for a wide range of applications. Their requirements pose new challenges for
sensor network designs, such as optimizing traditional solutions for use as environmental monitoring-like applications and
developing on-the-field stress tests. In this paper, we demonstrate the flexibility of a custom-designed WBASN called WiMoCA
with respect to a wide range of posture and activity recognition applications by means of practical implementation and on-the-field
testing. Nodes of the network mounted on different parts of the human body exploit tri-axial accelerometers to detect its
movements. The advanced digital Micro-electro-mechanical system (MEMS) based inertial sensor has been chosen for WiMoCA because
it demonstrated high flexibility of use in many different situations, providing the chance to exploit both static and dynamic
acceleration components for different purposes. Furthermore, the sensibility and accuracy of the sensing element is perfectly
adequate for monitoring human movement, while keeping cost low and size compact, thus meeting our requirements. We implemented
three types of applications, stressing the WBASN in many aspects. In fact, they are characterized by different requirements
in terms of accuracy, timeliness, and computation distributed on sensing nodes. For each application, we describe its implementation,
and we discuss results about performance and power consumption.
相似文献
Andrea AcquavivaEmail: |