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51.
Cornelia Kappeler-Setz Franz Gravenhorst Johannes Schumm Bert Arnrich Gerhard Tröster 《Personal and Ubiquitous Computing》2013,17(2):261-271
Manic depression, also known as bipolar disorder, is a common and severe form of mental disorder. The European research project MONARCA aims at developing and validating mobile technologies for multi-parametric, long term monitoring of physiological and behavioral information relevant to bipolar disorder. One aspect of MONARCA is to investigate the long term monitoring of Electrodermal activity (EDA) to support the diagnosis and treatment of bipolar disorder patients. EDA is known as an indicator of the emotional state and the stress level of a person. To realize a long-term monitoring of the EDA, the integration of the sensor system in the shoe or sock is a promising approach. This paper presents a first step towards such a sensor system. In a feasibility study including 8 subjects, we investigate the correlation between EDA measurements at the fingers, which is the most established sensing site, with measurements of the EDA at the feet. The results indicate that 88% of the evoked skin conductance responses (SCRs) occur at both sensing sites. When using an action movie as psychophysiologically activating stimulus, we have found weaker reactivity in the foot than in the hand EDA. The results also suggest that the influence of moderate physical activity on EDA measurements is low and has a similar effect for both recording sites. This suggests that the foot recording location is suitable for recordings in daily life even in the presence of moderate movement. 相似文献
52.
TeraGrid Science Gateways and Their Impact on Science 总被引:1,自引:0,他引:1
Wilkins-Diehr Nancy Gannon Dennis Klimeck Gerhard Oster Scott Pamidighantam Sudhakar 《Computer》2008,41(11):32-41
The Science Gateways program seeks to provide researchers with easy access to TeraGrid's high-performance computing resources. A look at four successful gateways illustrates the program's goals, challenges, and opportunities. 相似文献
53.
Stella Clarke Gerhard Schillhuber Michael F. Zaeh Heinz Ulbrich 《Multimedia Systems》2008,13(4):253-261
The remote nature of telepresence scenarios can be seen as a strongpoint and also as a weakness. Although it enables the remote
control of robots in dangerous or inaccessible environments, it necessarily involves some kind of communication mechanism
for the transmission of control signals. This communication mechanism necessarily involves adverse network effects such as
delay. Three mechanisms aimed at improving the effects of network delay are presented in this paper: (1) Motion prediction
to partially compensate for network delays, (2) force prediction to learn a local force model, thereby reducing dependency
on delayed force signals, and (3) haptic data compression to reduce the required bandwidth of high frequency data. The utilized
motion prediction scheme was shown to improve operator performance, but had no influence on operator immersion. The force
prediction provided haptic feedback through synchronous forces from the local model, thereby stabilizing the control loop.
The developed haptic data compression scheme reduced the number of packets sent across the network by 90%, while improving
the quality of the haptic feedback. 相似文献
54.
Smart card technology has evolved over the last few years following notable improvements in the underlying hardware and software platforms. Advanced smart card microprocessors, along with robust smart card operating systems and platforms, contribute towards a broader acceptance of the technology. These improvements have eliminated some of the traditional smart card security concerns. However, researchers and hackers are constantly looking for new issues and vulnerabilities. In this article we provide a brief overview of the main smart card attack categories and their corresponding countermeasures. We also provide examples of well-documented attacks on systems that use smart card technology (e.g. satellite TV, EMV, proximity identification) in an attempt to highlight the importance of the security of the overall system rather than just the smart card. 相似文献
55.
For many years, public transportation systems have been an essential part of day-to-day life and so the principle of needing a “ticket” has been familiar to generations of travellers. However as technology has advanced it has become possible to make use of electronic tickets that have significant advantages both for travellers and for the transport system operators. There has been a lot of recent publicity regarding weaknesses in some electronic ticket solutions; which whilst based on some solid facts tend to suggest that transport ticket security and fraud control is primarily a smart card/RFID technology issue. However this cannot be the case as systems exist that do not use such technology; or use it along side legacy systems. This paper will consider technology problems, but will first establish the bigger picture of transport ticketing and will finally make suggestions for future evolution of such systems. 相似文献
56.
Hendrik Voigt Aaron Rigoni Evgeniy Boltynjuk Mohammed Reda Chellali Bonnie Tyler Harald Rösner Sergiy Divinski Horst Hahn Gerhard Wilde 《Advanced functional materials》2023,33(44):2302386
Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable. 相似文献
57.
58.
Optimized Photoinitiator for Fast Two‐Photon Absorption Polymerization of Polyester‐Macromers for Tissue Engineering 下载免费PDF全文
59.
Glass capillaries with a chemically sensitive coating on the inner surface are used as optical sensors for medical diagnostics. A capillary simultaneously serves as a sample compartment, a sensor element, and an inhomogeneous optical waveguide. Various detection schemes based on absorption, fluorescence intensity, or fluorescence lifetime are described. In absorption-based capillary waveguide optrodes the absorption in the sensor layer is analyte dependent; hence light transmission along the inhomogeneous waveguiding structure formed by the capillary wall and the sensing layer is a function of the analyte concentration. Similarly, in fluorescence-based capillary optrodes the fluorescence intensity or the fluorescence lifetime of an indicator dye fixed in the sensing layer is analyte dependent; thus the specific property of fluorescent light excited in the sensing layer and thereafter guided along the inhomogeneous waveguiding structure is a function of the analyte concentration. Both schemes are experimentally demonstrated, one with carbon dioxide as the analyte and the other one with oxygen. The device combines optical sensors with the standard glass capillaries usually applied to gather blood drops from fingertips, to yield a versatile diagnostic instrument, integrating the sample compartment, the optical sensor, and the light-collecting optics into a single piece. This ensures enhanced sensor performance as well as improved handling compared with other sensors. 相似文献
60.
Reasoning about change is a central issue in research on human and robot planning. We study an approach to reasoning about action and change in a dynamic logic setting and provide a solution to problems which are related to the Frame problem. Unlike most work on the frame problem the logic described in this paper is monotonic. It (implicitly) allows for the occurrence of actions of multiple agents by introducing non-stationary notions of waiting and test. The need to state a large number of frame axioms is alleviated by introducing a concept of chronological preservation to dynamic logic. As a side effect, this concept permits the encoding of temporal properties in a natural way. We compare the relative merits of our approach and non-monotonic approaches as regards different aspects of the frame problem. Technically, we show that the resulting extended systems of propositional dynamic logic preserve (weak) completeness, finite model property and decidability. 相似文献