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21.
In this paper, a method for environmental observation network design using the framework of spatial modeling with copulas is proposed. The methodology is developed to enlarge or redesign an existing monitoring network by taking the configuration which would increase the expected gain defined in a utility function. The utility function takes the estimation uncertainty, critical threshold value and gain-loss of a certain decision into account. In this approach, the studied spatial variable is considered as a random field in where variations in time is neglected and the variable of interest is static in nature. The uniqueness of this approach lies in the fact that the uncertainty estimation at the unsampled location is based on the full conditional distribution calculated as conditional copula in this study. Unlike the traditional Kriging variance which is a function of mere measurements density and spatial configuration of data points, the conditional copula account for the influence from data values. This is important specially if we are interested in purpose oriented network design (pond) as for example the detection of noncompliance with water quality standards, the detection of higher quantiles in the marginal probability distributions at ungauged locations, the presence or absence of a geophysical variable as soil contaminants, hydrocarbons, golds and so on. An application of the methodology to the groundwater quality parameters in the South-West region of Germany shows its potential.  相似文献   
22.
Link analysis (LA) is a popular ergonomic tool for studying and improving the layout of workspaces. It uses a data (event) recording method to input interactions of human behavior with their environment. The traditional “pen and paper'' method of LA is cumbersome, time consuming, and gives limited outputs. To address these limitations, the computerized link analysis (CLA) system was developed and tested in laboratory and real‐world environments. CLA offers an integrated task analysis tool, including traditional LA functions (layout, event recording) with more detail for operator activities, time‐motion functions, and multioperator data recording. As well as the conventional LA results (link diagrams and link tables), there are additional outputs for time‐event lists (start/end time, duration, chronology, additional notes, importance, and operator ID), and processed link diagrams with the link direction and frequency. © 2012 Wiley Periodicals, Inc.  相似文献   
23.
观测几何对目标探测性能影响的仿真分析   总被引:1,自引:0,他引:1  
在光电武器作战探测目标性能问题的研究中,不同大气/气溶胶模式、不同观测几何条件下的光电武器作战效能差异显著.针对上述问题,通过分析大气传输和观测几何对视在对比度的影响,建立了视在对比度传递模型,结合TIP准则提出了观测几何对目标探测性能的影响模型.利用Modtran软件离线计算的基础数据,提出了探测性能模型快速仿真计算方法,实现了典型地区、全天时、不同观测几何和观测距离条件下的成像系统探测性能的快速仿真计算.采用快速仿真计算方法,选取典型参数,计算并分析了不同大气/气溶胶模式、观测几何等因素对视在对比度、探测概率和探测距离等指标的影响.结果表明:观测几何对目标探测性能影响显著,50%探测概率条件下,顺光探测距离是逆光探测距离的1.38 ~1.7倍;不同大气/气溶胶模式条件下,观测几何对探测距离影响差异明显,海洋性气溶胶模式下影响较大,乡村型气溶胶模式下影响较小.文中提出了观测几何对目标探测性能的影响模型和快速仿真计算方法,为光电武器系统任务规划和作战效能评估提供了理论和技术支持.  相似文献   
24.
本文从泛系的观点来分析了Linux操作系统中观控的思想,辩异同的思想,以及形影关系。旨在通过这些实例来说明这些思想,为我们在认识复杂的计算机系统方面寻求理论上的支持。  相似文献   
25.
Contrary to common belief, back pain amongst young people is a frequent phenomenon. Epidemiological studies have found high prevalence rates of back pain amongst schoolchildren. The investigation reported here aims to validate children's self-reporting and the observation of sitting postures to establish the intensity, duration and frequency of exposure in the classroom. The sitting postures of 18 children were recorded using three methods, the portable ergonomic observation method (PEO), video analysis and self-report. The three methods were compared. PEO was significantly correlated with video analysis of the sitting postures after development of the method. Self-report was not significantly correlated with video analysis of the sitting postures. Therefore PEO was selected as the main observation tool in further analysis of children's sitting posture in schools in South-East England as part of a large research programme investigating back pain amongst schoolchildren.  相似文献   
26.
标记迁移系统是一种在计算机辅助设计和验证中得到广泛使用的形式模型。当系统中的模块比较多时,系统的整体模型有可能出现状态空间的指数级爆炸,组合可达性分析是缓解这一问题的一种有效方法。已有的工作缺乏对该方法基本原理的清晰描述和精确表达。本文对其基本原理进行了分析和概括,并作了形式化陈述,证明了相关结论。本文的工作有助于深入理解和澄清组合可达性分析的内部工作机制。  相似文献   
27.
陈贵  杨浩 《煤矿开采》2003,8(4):55-58,61
通过现场观测,分析了朱仙庄矿高地应力特厚极软煤层轻放开采工作面支架支护阻力变化、巷道变形及顶煤顶板运移规律。认为该条件下所选轻放支架工作阻力合理,支承压力峰值点、顶煤顶板始动点与一般综放工作面相比,均前移,巷道变形严重。  相似文献   
28.
On the path to high-level vehicle automation, the degree of surveillance both inside and outside the car increases significantly. Consequently, ethical considerations are becoming central to questions around surveillance regimes and data privacy implicit in level 3 and 4 vehicle automation. In this paper, we focus on outputs from the EU Horizon 2020 project Vision Inspired Driver Assistance Systems (VI-DAS). In particular, we assess the VI-DAS 720-degree observation technology, critical to ensuring a safe Human Machine Interaction (HMI), from multiple theoretical perspectives to contribute to a better understanding of the phenomena of privacy. As a synonym for surveillance, we started our evaluation with Bentham's ideation of the panopticon. From there, it is a relatively short step to radical Foucauldian critiques that offered more dystopian technologies of power. However, both theorems demonstrate a limited understanding of the issue of data privacy in the context of safe transportation along the evolution of highly automated vehicles. Thus, to allow the debate to move beyond more binary discussions on privacy versus control/power and to a certain degree escape the shadow of the panopticon, we applied the Nissenbaum four theses framework of Contextual Integrity (CI). Her decision heuristic allowed us to introduce structure and a degree of precision in our thinking on the matter of privacy that represents a step forward to phenomena of privacy in a specific context. Our approach concludes that the VI-DAS 720-degree observation technology can respect the user's privacy through an appropriate flow of personal information. However, the flows of personal data must be strongly regulated to ensure that data is seen as a value in terms of a commodity to protect human life and not seen as an asset that needs to be turned into value in terms of capital or the facilitation of asymmetric power-relations.  相似文献   
29.
本文介绍了一种用于EAS观测阵列的在面积闪烁计数器的标定。对系统脉冲幅度通道及快速时间通道的标定均采用了NIM/CAMAC电子学系统。  相似文献   
30.
The problem of what is observable in general relativity is investigated.It is proposed that what is observable in curved spacetime is Lorentz quantity instead of Riemann quantity,With the help of Landau‘s observable space interval,the observational frames for individual observers are also established.  相似文献   
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