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31.
The race for creating an automated patch clamp has begun. Here, we present a novel technology to produce true gigaseals and whole cell preparations at a high rate. Suspended cells are flushed toward the tip of glass micropipettes. Seal, whole-cell break-in, and pipette/liquid handling are fully automated. Extremely stable seals and access resistance guarantee high recording quality. Data obtained from different cell types sealed inside pipettes show long-term stability, voltage clamp and seal quality, as well as block by compounds in the pM range. A flexible array of independent electrode positions minimizes consumables consumption at maximal throughput. Pulled micropipettes guarantee a proven gigaseal substrate with ultra clean and smooth surface at low cost. 相似文献
32.
The long-term variability of the fetal heart rate (FHR) provides valuable information on the fetal health status. The routine clinical FHR measurements are usually carried out by the means of ultrasound cardiography. Although the frequent FHR monitoring is recommendable, the high quality ultrasound devices are so expensive that they are not available for home care use. The passive and fully non-invasive acoustic recording called phonocardiography, provides an alternative low-cost measurement method. Unfortunately, the acoustic signal recorded on the maternal abdominal surface is heavily loaded by noise, thus the determination of the FHR raises serious signal processing issues. The development of an accurate and robust fetal phonocardiograph has been since long researched. This paper presents a novel two-channel phonocardiographic device and an advanced signal processing method for determination of the FHR. The developed system provided 83% accuracy compared to the simultaneously recorded reference ultrasound measurements. 相似文献
33.
Aggregate architectures are full-scale spatial formations made from loose granular matter. Especially if the individual grain is custom-designed, the range of behaviours can be calibrated to match a wide range of architectural and structural performance criteria. The aggregate becomes programmable matter. The relevance of loose granular systems for architecture is on the one hand their rapid re-configurability, allowing for a system not to be destroyed but rather to be recycled. On the other hand aggregates per se can be functionally graded either within one and the same particle type or through mixing different particle geometries. This enables the variation of architectural properties throughout one and the same material system, which is one of the core postulates of current architectural design research. However, very few examples of designed granular matter in architecture exist. The results presented here are thus one of the first coherent bodies of comprehensive research in this field compiled over a period of five years. Methodologically aggregate systems challenge conventional architectural design principles: whereas an architect generally precisely defines local and global geometry of a structure, in a designed granular system he can only calibrate the particle geometry in order to tune the overall behaviour of the aggregate formation. Thus new design methods have been developed throughout the research projects, which are informed by the related fields of granular physics and behaviour-based robotics. In this context the article provides an introduction to both designed particle systems and suitable fabrication approaches in an architectural context. Case study projects serve to verify the applicability of the concepts introduced. The research findings are discussed with regards to their practical, methodological and design theoretical contributions. To conclude, further directions of research are highlighted. 相似文献
34.
Codifying expert domain knowledge is a difficult and expensive task. To evaluate the quality of the outcome, often the same domain expert or a colleague of similar expertise is relied on to undertake a direct evaluation of the knowledge-based system or indirectly by preparing appropriate test data. During an incremental knowledge acquisition process, a data stream is available, and the knowledge base is observed and amended by an expert each time it produces an error. Using the kept record of the system’s performance, we propose an evaluation process to estimate its effectiveness as it gets evolved. We instantiate this process for an incremental knowledge acquisition methodology, Ripple Down Rules. We estimate the added value in each knowledge base update. Using these values, the decision makers in the organisation employing the knowledge-based information system can apply a cost-benefit analysis of the continuation of the incremental knowledge acquisition process. They can then determine when this process, involving keeping an expert online, should be terminated. As a result, the expert is not kept on-line longer than it is absolutely necessary. Hence, a major expense in deploying the information system—the cost of keeping a domain expert on-line—is reduced. 相似文献
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A semitheoretical equation of state has been used to correlate residual thermodynamic properties of heavy hydrocarbons. The correlation requires three characteristic molecular parameters obtained from liquid density and vapour pressure data. These parameters are presented for 61 hydrocarbons with molecular weights up to 560 and are correlated with molecular weight and structural features. The correlation is extended to narrow-boiling fractions. Molecular parameters for such fractions are obtained from experimental characterization data (molecular weight, aromaticity, naphthenicity and number of methyl groups per molecule). Calculated vapour pressures and liquid densities are in reasonable agreement with new experimental results obtained from Belridge crude oil. 相似文献
38.
An Al96.1–Cu3.9 to Al51.4–Cu48.6 material library was obtained by thermal co-deposition and characterized by EDX and XRD. The crystallographic data reveals the presence of Al2Cu and pure aluminium depending on the film composition and following the stoichiometry. Utilizing a scanning droplet cell setup, the zero current potential for anodization, the oxide formation factor and the dielectric constant of the oxide formed are presented with high resolution along the composition gradient.While the dielectric constant of the oxide formed remains nearly unaffected by the increasing copper content of the base material along the composition gradient, the zero current potential shows well defined steps between 6.9 and 8.5 at.% as well as between 20.9 and 26.7 at.% copper indicating an increased thickness of the native oxide present on the film. Additionally, starting around 25 at.% copper, oxygen evolution gradually superimposes the oxide growth and in turn significantly reduces the current efficiency for anodization. The formation of the intermetallic phase Al2Cu was linked to both phenomena as it promotes the growth of native oxides and current leakage by oxygen evolution. 相似文献
39.
This paper describes the system dimensioning and the radio network planning methodology for a third generation wcdma system. The applicability of each method is demonstrated using examples of likely system scenarios. The challenges of modeling the multiservice environment are described and the implications to the system performance simulations are introduced. 相似文献
40.
Aufgrund vieler Untersuchungen zur Standsicherheit von Eissporthallen wurde festgestellt, dass diese in unterschiedlichem Maße saniert werden müssen. Die Holzfeuchtigkeit der Tragkonstruktionen betrug meistens langanhaltend über 20 %. Daher wurden Untersuchungen zu den Ursachen hoher Holzfeuchten in Eissporthallen durchgeführt. Eine der Ursachen liegt in dem Strahlungsaustausch zwischen der Hallendecke und der Eisfläche. Zu dieser Problematik wurden Versuche durchgeführt und daraus mögliche Verbesserungsvorschläge für Eissporthallen abgeleitet. About the humidity problem in ice rinks. After expertising the structural safety of several ice rinks, it was detected that the constructions of several buildings have to be redeveloped. The long lasting wood moisture of the main structure was predominantly over 20 %. Therefore research into the reason of high wood moisture in ice rinks was made. One fact is the exchange of radiation between the ceiling and the ice. This problem was analysed in tests and suggestions for improvement are made. 相似文献