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31.
We investigate quantitative extensions of modal logic and the modal μ-calculus, and study the question whether the tight connection between logic and games can be lifted from the qualitative
logics to their quantitative counterparts. It turns out that, if the quantitative μ-calculus is defined in an appropriate way respecting the duality properties between the logical operators, then its model
checking problem can indeed be characterised by a quantitative variant of parity games. However, these quantitative games
have quite different properties than their classical counterparts, in particular they are, in general, not positionally determined.
The correspondence between the logic and the games goes both ways: the value of a formula on a quantitative transition system
coincides with the value of the associated quantitative game, and conversely, the values of quantitative parity games are
definable in the quantitative μ-calculus. 相似文献
32.
Standard path control laws of autonomous vehicles use the shortest distance between the vehicle’s position and the path as a control error. In order to determine this distance, the projection point onto the path needs to be determined continuously. This requires fast algorithms that feature high numerical reliability in the field of vehicle application.This paper presents two different observer-based approaches for the projection problem. The identity observer reconstructs all states of interest for path control. The second one, a reduced observer, only possesses the curve parameter as a state and calculates the other values by algebraic formulas. Both algorithms consider the continuous movement of the vehicle, the run of the curve, and work without any approximation of the curve. Furthermore, they are applicable for arbitrary parameterized smooth curves, guarantee the required numerical stability, have short calculating time, and show good statistical properties. The performance is shown in several simulations as well as under real conditions. 相似文献
33.
This paper reexamines the construction of indicators of standards of living, by focussing on the challenges raised by the
subjectivity and the multidimensionality of living conditions. For that purpose, we apply Choquet integral-based multiattribute
value theory to the elicitation, from rankings of multiattribute hypothetical societies, of individual preferences on different
dimensions of living conditions. A simple application of the proposed approach highlights that preferences on multiattribute
societies cannot, in general, be represented by an additive value model, as there exist complementarities and redundancies
between different dimensions of standards of living. Our elicitation exercise reveals also a strong heterogeneity of individual
preferences on hypothetical societies. Finally, we explore how elicited preferences can be used to cast a new light on the
ranking of actual societies. 相似文献
34.
The study evaluated the efficiency of two heat dissipation strategies under simulated desert patrol missions. Ten men participated in four trials, during which they walked on a treadmill (45°C, 20% relative humidity), carrying a load of 35 kg; two 50-min walks were separated by a 20-min rest. Cooling strategies, provided by an ambient air-ventilated vest (active cooling condition, AC), or water spraying of the skin during the rest (passive cooling condition, PC), in addition to reduced clothing and open zippers, were compared to conditions with full protective (FP) clothing and naked condition (NC). Skin temperature was higher during NC (37.9 ± 0.4°C; p < 0.001), and rectal temperature and heart rate were higher during FP (38.6 ± 0.4°C, p < 0.001 and 145 ± 12, p < 0.001, respectively), compared to other conditions. Four subjects terminated the trial prematurely due to signs of heat exhaustion in FP. Both cooling strategies substantially improved evaporative cooling. 相似文献
35.
36.
Termeer M Oliván Bescós J Breeuwer M Vilanova A Gerritsen F Gröller ME Nagel E 《IEEE transactions on visualization and computer graphics》2008,14(6):1595-1602
Visually assessing the effect of the coronary artery anatomy on the perfusion of the heart muscle in patients with coronary artery disease remains a challenging task. We explore the feasibility of visualizing this effect on perfusion using a numerical approach. We perform a computational simulation of the way blood is perfused throughout the myocardium purely based on information from a three-dimensional anatomical tomographic scan. The results are subsequently visualized using both three-dimensional visualizations and bull's eye plots, partially inspired by approaches currently common in medical practice. Our approach results in a comprehensive visualization of the coronary anatomy that compares well to visualizations commonly used for other scanning technologies. We demonstrate techniques giving detailed insight in blood supply, coronary territories and feeding coronary arteries of a selected region. We demonstrate the advantages of our approach through visualizations that show information which commonly cannot be directly observed in scanning data, such as a separate visualization of the supply from each coronary artery. We thus show that the results of a computational simulation can be effectively visualized and facilitate visually correlating these results to for example perfusion data. 相似文献
37.
Behavioral detection differs from appearance detection in that it identifies the actions performed by the malware rather than
syntactic markers. Identifying these malicious actions and interpreting their final purpose is a complex reasoning process.
This paper draws up a survey of the different reasoning techniques deployed among the behavioral detectors. These detectors
have been classified according to a new taxonomy introduced inside the paper. Strongly inspired from the domain of program
testing, this taxonomy divides the behavioral detectors into two main families: simulation-based and formal detectors. Inside
these families, ramifications are then derived according to the data collection mechanisms the data interpretation, the adopted
model and its generation, and the decision support. 相似文献
38.
Langlotz U Grützner PA Bernsmann K Kowal JH Tannast M Caversaccio M Nolte LP 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2007,221(7):739-753
Computer assisted orthopaedic surgery (CAOS) technology has recently been introduced to overcome problems resulting from acetabular component malpositioning in total hip arthroplasty. Available navigation modules can conceptually be categorized as computer tomography (CT) based, fluoroscopy based, or image-free. The current study presents a comprehensive accuracy analysis on the computer assisted placement accuracy of acetabular cups. It combines analyses using mathematical approaches, in vitro testing environments, and an in vivo clinical trial. A hybrid navigation approach combining image-free with fluoroscopic technology was chosen as the best compromise to CT-based systems. It introduces pointer-based digitization for easily assessable points and bi-planar fluoroscopy for deep-seated landmarks. From the in vitro data maximum deviations were found to be 3.6 degrees for inclination and 3.8 degrees for anteversion relative to a pre-defined test position. The maximum difference between intraoperatively calculated cup inclination and anteversion with the postoperatively measured position was 4 degrees and 5 degrees, respectively. These data coincide with worst cases scenario predictions applying a statistical simulation model. The proper use of navigation technology can reduce variability of cup placement well within the surgical safe zone. Surgeons have to concentrate on a variety of error sources during the procedure, which may explain the reported strong learning curves for CAOS technologies. 相似文献
39.
Larsen L Griffin LD Grässel D Witte OW Axer H 《Microscopy research and technique》2007,70(10):851-863
Polarized light imaging (PLI) is a method to image fiber orientation in gross histological brain sections based on the birefringent properties of the myelin sheaths. The method uses the transmission of polarized light to quantitatively estimate the fiber orientation and inclination angles at every point of the imaged section. Multiple sections can be assembled into a 3D volume, from which the 3D extent of fiber tracts can be extracted. This article describes the physical principles of PLI and describes two major applications of the method: the imaging of white matter orientation of the rat brain and the generation of fiber orientation maps of the human brain in white and gray matter. The strengths and weaknesses of the method are set out. 相似文献
40.
This contribution provides an introduction to the Common Information Model CIM which is an international standard maintained by the International Electrotechnical Commission IEC. Today’s market requirements towards the model are discussed, furthermore, we give an introduction to the history of the CIM, its serializations and scope of application. The contribution concludes with an overview of future use of the CIM for both science and commerce. Briefly, we focus on: Message-based loose coupling of information systems Exchange of power grid topologies with minimal communication and data overhead Data quality assurance using ontology-based meta annotations and Integration of heterogeneous standards in the utility domain. The contribution presents solutions to the use cases providing a better information management for the utility utilizing the Common Information Model. 相似文献