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31.
Visualization of diversity in large multivariate data sets 总被引:1,自引:0,他引:1
Pham T Hess R Ju C Zhang E Metoyer R 《IEEE transactions on visualization and computer graphics》2010,16(6):1053-1062
Understanding the diversity of a set of multivariate objects is an important problem in many domains, including ecology, college admissions, investing, machine learning, and others. However, to date, very little work has been done to help users achieve this kind of understanding. Visual representation is especially appealing for this task because it offers the potential to allow users to efficiently observe the objects of interest in a direct and holistic way. Thus, in this paper, we attempt to formalize the problem of visualizing the diversity of a large (more than 1000 objects), multivariate (more than 5 attributes) data set as one worth deeper investigation by the information visualization community. In doing so, we contribute a precise definition of diversity, a set of requirements for diversity visualizations based on this definition, and a formal user study design intended to evaluate the capacity of a visual representation for communicating diversity information. Our primary contribution, however, is a visual representation, called the Diversity Map, for visualizing diversity. An evaluation of the Diversity Map using our study design shows that users can judge elements of diversity consistently and as or more accurately than when using the only other representation specifically designed to visualize diversity. 相似文献
32.
The flow of a model non-polar liquid through small carbon nanotubes is studied using non-equilibrium molecular dynamics simulation.
We explain how a membrane of small-diameter nanotubes can transport this liquid faster than a membrane consisting of larger-diameter
nanotubes. This effect is shown to be back-pressure dependent, and the reasons for this are explored. The flow through the
very smallest nanotubes is shown to depend strongly on the depth of the potential inside, suggesting atomic separation can
be based on carbon interaction strength as well as physical size. Finally, we demonstrate how increasing the back-pressure
can counter-intuitively result in lower exit velocities from a nanotube. Such studies are crucial for optimisation of nanotube
membranes. 相似文献
33.
Dr. Alexander Benlian Prof. Dr. Thomas Hess Prof. Dr. Peter Buxmann 《WIRTSCHAFTSINFORMATIK》2009,51(5):414-428
Software-as-a-Service (SaaS) is said to become an important cornerstone of the Internet of Services. However, while some market research and IT provider firms fervently support this point of view, others already conjure up the failure of this on-demand sourcing option. Oftentimes based on weak empirical data and shaky reasoning, these inconsistent perspectives lack scientific rigor and neglect to present a more differentiated picture of SaaS-adoption. This study seeks to deepen the understanding of factors driving the adoption of Software-as-a-Service (SaaS). Grounded in transaction cost theory, the resource-based view, and the theory of planned behavior, the authors develop a research model to assess SaaS-adoption at the application level. Survey data of 297 firms in Germany with 374 valid response items across different industries were collected to test the theoretical model. Our analysis revealed that patterns of the decision on SaaS-adoption differ across application types. Social influence, attitude toward SaaS-adoption, adoption uncertainty, and strategic value turned out to be the strongest and most consistent drivers across all application types. Furthermore, it was found that firm size does not matter in SaaS-adoption, since large enterprises and small- and medium-sized companies had similar adoptation rates. Overall, this study provides relevant findings that IT vendors can use to better appeal to potential companies that consider adopting SaaS. 相似文献
34.
Benno Stein 《International Journal on Software Tools for Technology Transfer (STTT)》2008,10(3):233-245
This paper is about tool support for knowledge-intensive engineering tasks. In particular, it introduces software technology
to assist the design of complex technical systems. There is a long tradition in automated design problem solving in the field
of artificial intelligence, where, especially in the early stages, the search paradigm dictated many approaches. Later, in
the so-called modern period, a better problem understanding led to the development of more adequate problem solving techniques.
However, search still constitutes an indispensable part in computer-based design problem solving—albeit many human problem
solvers get by without (almost). We tried to learn lessons from this observation, and one is presented in this paper. We introduce
design problem solving by functional abstraction which follows the motto: construct a poor solution with little search, which then must be repaired. For the domain of fluidic
engineering we have operationalized the paradigm by the combination of several high-level techniques. The red thread of this
paper is design automation, but the presented technology does also contribute in the following respects: (a) productivity
enhancement by relieving experts from auxiliary and routine tasks; (b) formulation, exchange, and documentation of knowledge
about design; (c) requirements engineering, feasibility analysis, and validation.
This research was supported by DFG grants Schw 120/56-3, KL 529/10-3, KL 529/7-3, and KL 529/10-1. 相似文献
35.
A beam of charged vortex rings is used to study the vorticity present downstream from an array of 2-m-diameter orifices through which a steady flow of superfluid 4He is driven at known velocity and pressure head p. From the measured attentuation of the beam at low p, we infer a density of vortex line less than predicted by the Feynman critical velocity model. Possible explanations are considered. We find evidence that an interconnected tangle of vortices is formed above a certain value of p, which is in reasonable agreement with theory, at least for one orifice plate. Charge transfer and transient attenuation measurements indicate that this tangle decays in part into small vortex rings. These results are compared with an earlier experiment of Gamota.Research supported in part by the National Science Foundation under grant DMR 72-02971. 相似文献
36.
37.
Hans-Ulrich Waiblinger Miriam Schillinger Norbert Hess 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2012,7(2):163-170
Here, we describe the procedure of a DNA extraction method from maize starch including the method??s validation by in-house and interlaboratory tests. The amplifiable amount of maize DNA tested by real-time PCR was used as parameter for evaluating our method. The practical (i.e. relative) limit of detection (LOD) was used as key criterion for assessing the suitability of the extraction method with respect to genetically modified organism analysis. In a round-robin test with ten participating laboratories, satisfactory results were achieved with practical LODs in the range of 0.1?% with three native maize starch materials. In-house tests showed that this protocol??with an additional purification step??can also be applied for extracting DNA from chemically or enzymatically modified starch. 相似文献
38.
Scientometrics - Although scientists, like many other professionals, aspire to fame and recognition, research in the emergent field of fame and celebrity has as yet neglected to explore their fame... 相似文献
39.
Mulloni Viviana Margesin Benno Farinelli Paola Marcelli Romolo Lucibello Andrea De Angelis Giorgio 《Microsystem Technologies》2017,23(9):3843-3850
Microsystem Technologies - Contact resistance is the main parameter used for assessing the high cycling reliability of RF microelectromechanical (RF-MEMS) switches. In this paper the use of a... 相似文献
40.
The Suspicion of Simulation. A Psychiatric Case History between Appropriation and Disciplinary Action at the End of the 19th
Century.
This case history explores how the question of agency was dealt with historically in two developing, normative orders of deviant
behaviour. Examining the institutional career of the supposed adulterer, marriage swindler, and craft baker, we can trace
the different observation regimes and systems of knowledge acquisition in the prison and in psychiatry. In both institutions
there was talk of simulated madness; the explanations, however, were different. For the prison doctors and civil servants,
the baker was a criminal; his deviant behaviour was a matter of consciously planned-out deception. For the examining psychiatrist,
on the other hand, he was mentally ill and could not be held responsible for his own behaviour. 相似文献