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61.
In this paper, we present a method to monitor count data so as to be able to detect improvement when the counts are low enough to cause the lower limit to be zero. The method, which is proposed as an add-on to the conventional Shewhart control chart, consists in counting the number of samples in which zero defectives or zero defects per unit occur and signaling an increase in quality if k-in-a-row or 2-in-t samples have zero counts of defectives or zero defects per unit. This method enjoys some similarities to the very popular Shewhart control chart in that it is easy to design, understand and use. It is flexible, robust, and, like the Shewhart chart, yields detection frequencies that are optimal for very large shifts and good for other shifts. Some comparisons with traditional CUSUM charts are provided. Figures enabling Shewhart control chart users to easily design low-side add-on control charts are given for c and np charts. 相似文献
62.
Lucas D Introna 《欧洲信息系统杂志》2003,12(3):235-240
This paper provides a critical discussion of the ongoing concern of Information Systems (IS) academics on the status of IS as an academic discipline. The focal claim of the argument is that the status of IS as an ‘academic discipline’ is not an ontological or an epistemological question but rather a political one. In defending this claim the paper will draw on the work of Foucault, in particular his discussion on the relation between power and knowledge. The paper will conclude that the advice given by Paul (2002) and others may be appropriate but for very different reasons. It will claim that it is equally important, if not more so, to know the reasons why claims to legitimacy may succeed or not, for such claims to be effective as a political programme. 相似文献
63.
Mehrdad Boroushaki Mohammad B. Ghofrani Caro Lucas Mohammad J. Yazdanpanah Nasser Sadati 《Nuclear Engineering and Design》2004,227(3):285-300
Improved load following capability is one of the main technical performances of advanced PWR (APWR). Controlling the nuclear reactor core during load following operation encounters some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking, while the core is subject to large and sharp variation of local power density during transients. Axial offset (AO) is the parameter usually used to represent of core power peaking, in form of a practical parameter. This paper, proposes a new intelligent approach to AO control of PWR nuclear reactors core during load following operation. This method uses a neural network model of the core to predict the dynamic behavior of the core and a fuzzy critic based on the operator knowledge and experience for the purpose of decision-making during load following operations. Simulation results show that this method can use optimum control rod groups maneuver with variable overlapping and may improve the reactor load following capability. 相似文献
64.
In this paper, we attempt to show how phenomenology, in a traditional methodological form, can provide an interesting and novel basis for thinking about screens in a world where screens now pervade a great many aspects of human experience. In our analysis, we aim to give a phenomenological account of screen(ing), that is, of its fundamental and foundational meaning. In doing the phenomenological analysis, we ground our argument on the ontology of Heidegger's Being and Time. In doing this, we claim that the screen will only show itself, as that which it is, as a screen in-the-world, where screens already are or have their being ‘as screens’ for this and that purpose, activity or work. We claim, and aim to show, that our analysis provides many insights about the meaning of screens that would be difficult to gain through any other method of investigation. We also argue and show that, although our method is not empirical, its results have important implications for the empirical world. 相似文献
65.
M.R. Lucas D.M. Tilbury 《The International Journal of Advanced Manufacturing Technology》2005,26(5):436-447
Currently there is a wide variety of logic control design methodologies used in industrial logic design. These methodologies include ladder diagrams, function block diagrams, sequential function charts, and flow charts, but driven by a desire for verifiability, academics are developing additional logic control design methodologies, such as modular finite state machines and Petri nets. Using these, important properties of programs can be verified and some logic can be generated automatically from a part plan. The main contribution of this paper is to define methods for measuring programs written in different methodologies, so that the performance of the methodologies can be compared.We demonstrate these methods of measurement using four program samples that perform similar functions on the same machine, written in four logic control design methodologies: ladder diagrams, Petri nets, signal interpreted Petri nets and modular finite state machines. 相似文献
66.
A strategy for improving speed of the previously proposed evolving neuro-fuzzy model (ENFM) is presented in this paper to make it more appropriate for online applications. By considering a recursive extension of Gath?CGeva clustering, the ENFM takes advantage of elliptical clusters for defining validity region of its neurons which leads to better modeling with less number of neurons. But this necessitates the computing of reverse and determinant of the covariance matrices which are time consuming in online applications with large number of input variables. In this paper a strategy for recursive estimation of singular value decomposition components of covariance matrices is proposed which converts the burdensome computations to calculating reverse and determinant of a diagonal matrix while keeping the advantages of elliptical clusters. The proposed method is applied to online detection of epileptic seizures in addition to prediction of Mackey?CGlass time series and modeling a time varying heat exchanger. Simulation results show that required time for training and test of fast ENFM is far less than its basic model. Moreover its modeling ability is similar to the ENFM which is superior to other online modeling approaches. 相似文献
67.
Sustainable intensification (SI) has been proposed as a solution to meeting the challenge of feeding a growing global population under increasing land pressure. This paper explores the level of ambivalence felt towards SI and towards experts promoting SI based solutions to meet food security. A web-based experiment was conducted with 600 respondents who had varying degrees of knowledge about food security issues. We found a diversity of public ambivalence towards sustainable intensification and a high level of felt ambivalence towards experts promoting SI as a solution to global food security. High levels of ambivalence towards experts seemed to influence how messages on global food security were accepted. Moreover, within the respondents here sustainable consumption and greater equity ranked higher than production based sustainable intensification solutions. This paper represents the first application of the psychological construct of ambivalence applied to the topic of sustainable intensification and we argue this helps to localise the debate around SI as it offers the opportunity to capture or disentangle responses towards food security issues. 相似文献
68.
69.
Lucas Alves Da Silva Eric Dekneuvel Alexandre Lewicki Benjamin Nicolle Gilles Jacquemod 《Microelectronics Journal》2012,43(2):98-109
In this paper, we propose to develop a hierarchical library associated with various simulators that can be used in a single platform, called TrustMe-ViP, which enables a unique simulation framework and full model interoperability. Such platform is dedicated to complex SoC design, such as trusted personal devices where cost and time-to-market are very important constraints. To validate this methodology, we present the estimation of BER and power consumption for a Bluetooth transceiver. 相似文献
70.