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101.
Walter Lang Frank Jakobs Elena Tolstosheeva Hannes Sturm Azat Ibragimov Antonia Kesel Dirk Lehmhus Ursula DickeAuthor vitae 《Sensors and actuators. A, Physical》2011,171(1):3-11
Ubiquitous computing is about to become part of our everyday lives by integrating hundreds of “invisible” to us computing devices in our environment, so that they can unobtrusively and constantly assist us. This will imply more and smaller “invisible” sensors, homogeneously distributed and at the same time densely packed in host materials, responding to various stimuli and immediately delivering information. In order to reach this aim, the embedded sensors should be integrated within the host material, heading towards sensorial materials. The first step is to omit all parts that are not needed for the sensorial task and to find new solutions for a gentle integration. This is what we call function scale integration. The paper discusses sensor embedding in the human hand as an example of integration in nature, new technological applications and main challenges associated with this approach. 相似文献
102.
Effects of differences in office chair controls, seat and backrest angle design in relation to tasks
Liesbeth Groenesteijn Peter Vink Michiel de Looze Frank Krause 《Applied ergonomics》2009,40(3):362-370
In this study the influence of chair characteristics on comfort, discomfort, adjustment time and seat interface pressure is investigated during VDU and non-VDU tasks: The two investigated office chairs, both designed according to European and Dutch standards are different regarding: 1) seat cushioning and shape, 2) backrest angle and 3) controls. Thirty subjects in total, both male and female, participated in two experiments: twenty in the first and ten in the second.Significant differences are found for ease of adjustment and adjustment time of controls, independent of the tasks. Related to tasks, a significant difference was found for the backrest range of motion. For non-VDU tasks a larger range of backrest motion was preferred by 70% of the subjects. The chair design differences were most clear for comfort and adjustment time of controls, followed by comfort of backrest angle. No differences are found between seat pan comfort and discomfort, first impressions and peak interface pressure. 相似文献
103.
104.
It is widely believed that systems development methodologies (SDMs) can help improve the software development process. Nevertheless, their deployment often encounters resistance from systems developers. Agile methodologies, the latest batch of SDMs that are most suitable in dealing with volatile business requirements, are likely to face the same challenge as they require developers to drastically change their work habits and acquire new skills. This paper addresses what can be done to overcome the challenge to agile methodologies acceptance. We provide a critical review of the extant literature on the acceptance of traditional SDMs and agile methodologies, and develop a conceptual framework for agile methodologies acceptance based on a knowledge management perspective. This framework can provide guidance for future research into acceptance of agile methodologies, and has implications for practitioners concerned with the effective deployment of agile methodologies. 相似文献
105.
Muhammad F. Mysorewala Dan O. Popa Frank L. Lewis 《Journal of Intelligent and Robotic Systems》2009,54(4):535-565
The use of robotics in distributed monitoring applications requires wireless sensors that are deployed efficiently. A very
important aspect of sensor deployment includes positioning them for sampling at locations most likely to yield information
about the spatio-temporal field of interest, for instance, the spread of a forest fire. In this paper, we use mobile robots
(agents) that estimate the time-varying spread of wildfires using a distributed multi-scale adaptive sampling strategy. The
proposed parametric sampling algorithm, “EKF-NN-GAS” is based on neural networks, the extended Kalman filter (EKF), and greedy heuristics. It combines measurements arriving
at different times, taken at different scale lengths, such as from ground, airborne, and spaceborne observation platforms.
One of the advantages of our algorithm is the ability to incorporate robot localization uncertainty in addition to sensor
measurement and field parameter uncertainty into the same EKF model. We employ potential fields, generated naturally from
the estimated fire field distribution, in order to generate fire-safe trajectories that could be used to rescue vehicles and
personnel. The covariance of the EKF is used as a quantitative information measure for sampling locations most likely to yield
optimal information about the sampled field distribution. Neural net training is used infrequently to generate initial low
resolution estimates of the fire spread parameters. We present simulation and experimental results for reconstructing complex
spatio-temporal forest fire fields “truth models”, approximated by radial basis function (RBF) parameterizations. When compared
to a conventional raster scan approach, our algorithm shows a significant reduction in the time necessary to map the fire
field. 相似文献
106.
In this study, we apply a step-by-step approach for the identification of standards for home networking. We develop a classification and we use this classification to categorize sixty-four (sets of) standards. By developing this categorization, we have brought order to the chaos of home networking standards. 相似文献
107.
This article deals with real-time critical systems modelling and verification. Real-time scheduling theory provides algebraic
methods and algorithms in order to make timing constraints verifications of these systems. Nevertheless, many industrial projects
do not perform analysis with real-time scheduling theory even if demand for use of this theory is large and the industrial
application field is wide (avionics, aerospace, automotive, autonomous systems, …). The Cheddar project investigates why real-time scheduling theory is not used and how its usability can be increased. The project was
launched at the University of Brest in 2002. In Lecture Notes on Computer Sciences, vol. 5026, pp. 240–253, 2008, we have presented a short overview of this project. This article is an extended presentation of the Cheddar project, its contributions and also its ongoing works. 相似文献
108.
Acar Esra Hopfgartner Frank Albayrak Sahin 《Multimedia Tools and Applications》2017,76(9):11809-11837
Multimedia Tools and Applications - In today’s society where audio-visual content such as professionally edited and user-generated videos is ubiquitous, automatic analysis of this content is... 相似文献
109.
Output synchronization of a network of heterogeneous linear state–space models under time-varying and directed interconnection structures is investigated. It is shown that, assuming stabilizability and detectability of the individual systems and imposing very mild connectedness assumptions on the interconnection structure, an internal model requirement is necessary and sufficient for synchronizability of the network to polynomially bounded trajectories. The resulting dynamic feedback couplings can be interpreted as a generalization of existing methods for identical linear systems. 相似文献
110.