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991.
992.
Model-based process-monitoring procedures are extremely useful in situations where an output variable of interest is impacted by one or more inputs to the process, and where there are multistage processes with multiple inputs and outputs. To build the model relating input and output variables, the procedure uses historical data, which often contain outliers. To accommodate the presence of these outliers, a robust fitting scheme is introduced for the Generalized Linear Model in process monitoring. Robust deviance residuals are defined and used as the basis of the monitoring procedure. An example and a simulation study for a gamma-distributed response are included. The average run length performance reveals that the procedure is effective for detecting small process shifts when outliers are present. 相似文献
993.
Ronald D. Snee 《技术计量学》2013,55(3):230-237
In this discussion, we give a short overview of some of the uses of artificial neural networks in practice. This is not intended to be an exhaustive list, but it includes some widely used industrial examples with which we are familiar. From our experience, we also attempt to point out why they are used and what the relative advantages and disadvantages of using a neural network over a traditional statistical method might be. 相似文献
994.
Qualitative locations describe the locations of spatial objects by relating them to a reference frame with qualitative relations. Existing models concerned with regional partitions are mainly topology-based and do not consider the effects of scale changes on locations. This study develops a direction-based multi-scale qualitative location (DMQL) model to fill this gap. First, a cell partition is defined by extending the borders of the minimum bounding rectangles of the regions in a regional partition. Relating spatial objects to all regions by a set of directions is equal to representing the objects as a set of cells in a cell partition. Second, due to the multiple cell representations of spatial objects and the changes in direction relations across scales, some approaches are presented to derive the direction changes between regions in different frames, between spatial objects and regions, and between spatial objects at different scales. Third, the location and relation consistencies of qualitative locations are evaluated based on the cell representations of spatial objects at multiple scales through a case study. The results indicate that the DMQL model can locate objects more precisely than the topology-based models. 相似文献
995.
996.
基于某炮瞄训练模拟系统的应用,系统以STC12C5AXXS2系列增强型单片机为基础构建了硬件部分,首先对系统进行简要介绍,设计了硬件的框架图,对各功能的具体电路进行说明,并用C语言程序实现其功能. 相似文献
997.
审计是经济活动中非常重要的环节,它承担着审查监督、揭露经济犯罪等重要任务。然而在面对几何增长的数据量的时候,审计人员很难找到数据中隐藏的重要信息,影响自己的判断力。基于如此宏大的数据量,提出将数据仓库、数据挖掘及其算法应用到审计中,分析当前数据,对后期数据进行预测评估,为审计人员的决策提供数据支持。 相似文献
998.
We designed and applied interactive visualisation techniques for investigating how social networks are embedded in time and space, using data collected from smartphone logs. Our interest in spatial aspects of social networks is that they may reveal associations between participants missed by simply making contact through smartphone devices. Four linked and co-ordinated views of spatial, temporal, individual and social network aspects of the data, along with demographic and attitudinal variables, helped add context to the behaviours we observed. Using these techniques, we were able to characterise spatial and temporal aspects of participants’ social networks and suggest explanations for some of them. This provides some validation of our techniques.Unexpected deficiencies in the data that became apparent prompted us to evaluate the dataset in more detail. Contrary to what we expected, we found significant gaps in participant records, particularly in terms of location, a poorly connected sample of participants and asymmetries in reciprocal call logs. Although the data captured are of high quality, deficiencies such as these remain and are likely to have a significant impact on interpretations relating to spatial aspects of the social network. We argue that appropriately-designed interactive visualisation techniques–afforded by our flexible prototyping approach–are effective in identifying and characterising data inconsistencies. Such deficiencies are likely to exist in other similar datasets, and although the visual approaches we discuss for identifying data problems may not be scalable, the categories of problems we identify may be used to inform attempts to systematically account for errors in larger smartphone datasets. 相似文献
999.
针对物联网协议EPcc1G2中反向链路数据的解码技术,以精简硬件资源和提高解码效率为目标,给出了基于MCU硬件平台,并利用其中TIMER模块和ADC模块实现反向链路数据解码技术的设计分析和实现思路,同时以实际运用中对FM0解码实现为实例,对解码效果、关键技术点进行了分析;还在结论中将此解码技术与常用技术方案进行了扼要比较,阐明了相关技术特点,得出了本技术的比较优势。 相似文献
1000.
This paper presents a production control approach for the testing and rework cell in a dynamic and stochastic computer integrated manufacturing (CIM) system. The proposed situation dependent decision selector (SDDS) observes the status of the system and jobs at every decision point, and makes its three different decisions on dispatching, pre-emption, and dispatching within pre-emption in real time. This paper also develops a new feature selection algorithm for the SDDS. Experimental results show that the SDDS is better than other static control rules and another dynamic control approach with respect to the number of tardy jobs. 相似文献