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Stephan Simmuteit Frank-Michael Schleif Thomas Villmann Barbara Hammer 《Knowledge and Information Systems》2010,25(2):327-343
In this paper, we investigate the application of Evolving Trees (ET) for the analysis of mass spectrometric data of bacteria.
Evolving Trees are extensions of self-organizing maps (SOMs) developed for hierarchical classification systems. Therefore,
they are well suited for taxonomic problems such as the identification of bacteria. Here, we focus on three topics, an appropriate
pre-processing and encoding of the spectra, an adequate data model by means of a hierarchical Evolving Tree and an interpretable
visualization. First, the high dimensionality of the data is reduced by a compact representation. Here, we employ sparse coding,
specifically tailored for the processing of mass spectra. In the second step, the topographic information which is expected
in the fingerprints is used for advanced tree evaluation and analysis. We adapted the original topographic product for SOMs
for ET to achieve a judgment of topography. Additionally we transferred the concept of U-matrix for evaluation of the separability
of SOMs to their analog in ET. We demonstrate these extensions for two mass spectrometric data sets of bacteria fingerprints
and show their classification and evaluation capabilities in comparison to state of the art techniques. 相似文献
44.
This study explores how distributing the controls of a video game among multiple players affects the sociality and engagement experienced in game play. A video game was developed in which the distribution of game controls among the players could be varied, thereby affecting the abilities of the individual players to control the game. An experiment was set up in which eight groups of three players were asked to play the video game while the distribution of the game controls was increased in three steps. After each playing session, the players’ experiences of sociality and engagement were assessed using questionnaires. The results showed that distributing game control among the players increased the level of experienced sociality and reduced the level of experienced control. The game in which the controls were partly distributed led to the highest levels of experienced engagement, because the game allowed social play while still giving the players a sense of autonomy. The implications for interaction design are discussed. 相似文献
45.
Service orientation has been a major buzz-word in recent years. While the buzz is on a decline, organizations are slowly, but steadily moving towards service oriented designs. However, service orientation turns out to be as much of a managerial challenge as of a technical one. The most important complexity drivers in the service oriented design of information systems seem to be (a) inconsistent design goals of stakeholders and (b) the pursuit of exhaustive service orientation coverage. This research focuses on the following two questions: (1) What are the characteristics of successful implementations of service oriented information systems, and (2) what are the critical success factors influencing, driving and/or determining these characteristics? Data of an empirical analysis is used to test a set of cause-effect relationship hypotheses based on nine latent variables. In the core of this model we differentiate the variables ??overall service orientation infrastructure success?? and ??service orientation project success??. The hypothesized interrelationships between the nine variables lead to a causal model which is proven to hold. 相似文献
46.
Stephan Dürr 《Computer Physics Communications》2009,180(8):1338-1357
A Lie-algebra based recipe for smoothing gauge links in lattice field theory is presented, building on the matrix logarithm. With or without hypercubic nesting, this LOG/HYL smearing yields fat links which are differentiable with respect to the original ones. This is essential for defining UV-filtered (“fat link”) fermion actions which may be simulated with a HMC-type algorithm. The effect of this smearing on the distribution of plaquettes and on the residual mass of tree-level O(a)-improved clover fermions in quenched QCD is studied. 相似文献
47.
Grüne Computer 总被引:1,自引:1,他引:0
Stephan W. Eder 《WIRTSCHAFTSINFORMATIK》2009,51(1):145-147
Ohne Zusammenfassung
This article is also available in English via http://www.springerlink.com and http://www.bise-journal.org: Eder SW (2008)
Green Computers. Bus Inf Syst Eng. doi: . 相似文献
48.
Tomasz Fałat Kazimierz Friedel Norman Marenco Stephan Warnat 《Microsystem Technologies》2009,15(1):181-190
The current paper focuses on several mechanical aspects of a waferlevel packaging approach using a direct face-to-face Chip-to-Wafer
(C2W) bonding of a MEMS device on an ASIC substrate wafer. Requirements of minimized inherent stress from packaging and good
decoupling from forces applied in manufacturing and application are discussed with particular attention to the presence of
through-silicon vias (TSV) in the substrate wafer. The paper deals with FEM analysis of temperature excursion, pressure during
molding, materials used and handling load influence on mechanical stress within the TSV system and on wafer level, which can
be large enough to disintegrate the system. 相似文献
49.
Milosavljevic S Gregory DE Pal P Carman AB Milburn PD Callaghan JP 《Applied ergonomics》2011,42(6):801-806
Wool handling is an important rural occupation where workers process 200 or more fleeces daily, separating them into various quality components. Loads and postures they experience carry substantial risk of low back pain (LBP). Although a formal skill training structure exists, interaction with loads and LBP is unknown. We examined whether skill and LBP influenced trunk postures and loads of 60 wool handlers representing 3 skill levels. LBP prevalence ranged from 20% for junior (lowest skill) to 45% for open class (highest skill) wool handlers. Open class wool handlers demonstrated increased lateral bend and more axially twisted postures, generating greater medio-lateral shear forces and lateral bend and axial twist moments. LBP was associated with open class wool handlers spending more time in severe axially twisted postures. These findings suggest that skill-based training needs to be reviewed to reduce the quantity of axially twisted posture which may help reduce the prevalence of LBP in this workforce. 相似文献
50.