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排序方式: 共有3568条查询结果,搜索用时 406 毫秒
61.
Claire M. Côte Chris J. Moran Christopher J. Hedemann Christian Koch 《Environmental Modelling & Software》2010,25(12):1664-1671
Concerns about the difficulties in securing water have led the Australian coal mining industry to seek innovative ways to improve its water management and to adopt novel strategies that will lead to less water being used and more water being reused. Simulation tools are essential to assess current water management performance and to predict the efficiency of potential strategies. As water systems on coal mines are complex and consist of various inter-connected elements, a systems approach was selected, which views mine site water management as a system that obtains water from various sources (surface, groundwater), provides sufficient water of suitable quality to the mining tasks (coal beneficiation, dust suppression, underground operations) and maintains environmental performance. In this paper, the model is described and its calibration is illustrated. The results of applying the model for the comparison of the water balances of 7 coal mines in the northern Bowen Basin (Queensland, Australia) are presented. The model is used to assess the impact of applying specific water management strategies. Results show that a simple systems model is an appropriate tool for assessing site performance, for providing guidance to improve performance through strategic planning, and for guiding adoption of site objectives. 相似文献
62.
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
63.
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
64.
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
65.
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
66.
67.
Philippe Coni Jean‐Luc Bardon Aude Gueguen Matthieu Grossetête 《Journal of the Society for Information Display》2017,25(3):158-166
A 3D stereoscopic head‐up display using a tunable bandpass filter to perform left and right image spectral separation is presented. Using a single filter reduces the size and the cost of the head‐up display optical engine and enables each spectral band to be accurately tuned. Experiments performed on the first prototype demonstrate the ability to continuously tune the bandpass frequency on 30‐nm range while keeping a 20‐nm bandwidth. Such a system avoids the use of a bulky and costly rotating wheel and enables the use of holographic optical elements known to be wavelength selective. 相似文献
68.
Huth J Buchholz M Kraus JM Mølhave K Gradinaru C v Wichert G Gress TM Neumann H Kestler HA 《Computer methods and programs in biomedicine》2011,104(2):227-234
The direct observation of cells over time using time-lapse microscopy can provide deep insights into many important biological processes. Reliable analyses of motility, proliferation, invasive potential or mortality of cells are essential to many studies involving live cell imaging and can aid in biomarker discovery and diagnostic decisions. Given the vast amount of image- and time-series data produced by modern microscopes, automated analysis is a key feature to capitalize the potential of time-lapse imaging devices. To provide fast and reproducible analyses of multiple aspects of cell behaviour, we developed TimeLapseAnalyzer. Apart from general purpose image enhancements and segmentation procedures, this extensible, self-contained, modular cross-platform package provides dedicated modalities for fast and reliable analysis of multi-target cell tracking, scratch wound healing analysis, cell counting and tube formation analysis in high throughput screening of live-cell experiments. TimeLapseAnalyzer is freely available (MATLAB, Open Source) at http://www.informatik.uni-ulm.de/ni/mitarbeiter/HKestler/tla. 相似文献
69.
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
70.
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