1,432 research outputs found
A Concept For Data-Driven Decision-Making During The Production Ramp-Up To Increase Resilience In Value Networks
Manufacturing companies are challenged by an increased number of production ramp-ups in shorter intervals due to shorter product life cycles and dynamically changing customer demands. The complexity of new products and the corresponding production systems, particularly in the value network, adds to this challenge. This complexity leads to an increased number of disruptions during the production ramp-up, to which manufacturing companies must be able to adapt flexibly. Although methodological support is available, there is a lack of data-driven approaches for adapting and reacting to potential disruptions during the production ramp-up in the value network. Therefore, this article presents a concept for a data-driven approach in value networks during production ramp-ups to flexibly adapt to disruptions. First, a method for describing and categorizing disruptions and corresponding mitigation decisions is developed based on the ISO/IEC 20000 1. Second, an application method for a generic simulation model is created to generate synthetic disruption production ramp-up data for a given value network configuration and corresponding disruptions. Third and parallel, a method for assessing a manufacturing company's resilience in the value network during the production ramp-up is developed. In the final step, the synthetic data is used to train a data-driven model. This model selects appropriate mitigation decisions for disruptions based on data and can evaluate the impact of disruptions and mitigation decisions on key performance indicators specific to production ramp-up. The possible increase in company-specific resilience is assessed using the developed assessment method
Kant's Argument that Existence is not a Determination
In this paper, I examine Kant's famous objection to the ontological argument: existence is not a determination. Previous commentators have not adequately explained what this claim means, how it undermines the ontological argument, or how Kant argues for it. I argue that the claim that existence is not a determination means that it is not possible for there to be non-existent objects; necessarily, there are only existent objects. I argue further that Kant's target is not merely ontological arguments as such but the larger ‘ontotheist’ metaphysics they presuppose: the view that God necessarily exists in virtue of his essence being contained in, or logically entailed by, his essence. I show that the ontotheist explanation of divine necessity requires the assumption that existence is a determination, and I show that Descartes and Leibniz are implicitly committed to this in their published versions of the ontological argument. I consider the philosophical motivations for the claim that existence is a determination and then I examine Kant's arguments in the Critique of Pure Reason against i
Equipment and procedure for determining the elastic modulus of carbon-epoxy composites
Method includes test device design and fabrication and standard Naval Ordnance Laboratory /NOL/ test ring as the test specimen. Technique provides accurate measurement of NOL ring elastic modulus, and adapts for use with fiber glass epoxy/rings
The Gamma-Ray Imaging Spectrometer (GRIS): A new balloon-borne experiment for gamma-ray line astronomy
High resolution gamma-ray spectroscopy is a relatively new field that holds great promise for further understanding of high energy astrophysical processes. When the high resolution gamma-ray spectrometer (GRSE) was removed from the GRO payload, a balloon program was initiated to permit continued development and improvement of instrumentation in this field, as well as continued scientific observations. The Gamma-Ray Imaging Spectrometer (GRIS) is one of the experiments selected as part of this program. The instrument contains a number of new and innovative features that are expected to produce a significant improvement in source location accuracy and sensitivity over previous balloon and satellite experiments
A coded aperture imaging system optimized for hard X-ray and gamma ray astronomy
A coded aperture imaging system was designed for the Gamma-Ray imaging spectrometer (GRIS). The system is optimized for imaging 511 keV positron-annihilation photons. For a galactic center 511-keV source strength of 0.001 sq/s, the source location accuracy is expected to be + or - 0.2 deg
A twenty-first century perspective on concepts of modern epidemiology in Ignaz Philipp Semmelweis’ work on puerperal sepsis
We aimed to review Semmelweis’s complete work on puerperal sepsis mortality in maternity wards in relation to exposure to cadavers and chlorine handwashing and other factors from the perspective of modern epidemiological methods. We reviewed Semmelweis' complete work and data as published by von Györy 1905 according to current standards. We paid particular attention to Semmelweis's definition of mortality in and of itself, to concepts of modern epidemiology that were already recognizable in Semmelweis's work, and to bias sources. We did several quantitative bias analyses to address selection bias and information bias from outcome measurement error. Semmelweis addressed biases that have become known to modern epidemiology, such as confounding, selection bias and bias from outcome misclassification. Our bias analysis shows that differential loss to follow-up is an unlikely explanation for his results. Bias due to outcome misclassification would only be relevant if misclassification differed between time periods. Confounding by health status was likely but could not be quantitatively addressed. Semmelweis was aware that cause-specific mortality is a function of incidence and prognosis. He reasoned in potential outcome terms to estimate the reduced number of deaths from an intervention. He advanced a hypothesis of clinic overcrowding as a risk factor for puerperal sepsis mortality that turns out to be wrong. Semmelweis’ data provide a great pool for illustrating the logic of scientific discovery by use of the numerical method. The explanatory power of his work was strong and Semmelweis was able to refute several previous causal explanations
Kant’s Regulative Metaphysics of God and the Systematic Lawfulness of Nature
In the ‘Appendix to the Transcendental Dialectic’ of the Critique of Pure Reason, Kant contends that the idea of God has a positive regulative role in the systematization of empirical knowledge. But why is this regulative role assigned to this specific idea? Kant’s account is rather opaque and this question has also not received much attention in the literature. In this paper I argue that an adequate understanding of the regulative role of the idea of God depends on the specific metaphysical content Kant attributes to it in the Critique and other writings. I show that neither a heuristic principle of conceptual systematicity, nor conceiving God as a hypothesis of an intelligent designer, can satisfy the demands of reason to make the unity and necessity of the laws of nature intelligible. Regarding the positive account about the metaphysical content of the idea of God, I support my argument by referring to Kant’s pre-critical discussion of the usefulness of the conception of God for the project of science, and by expounding Kant’s critical account of the necessity of the laws of nature. Thus my account sheds light on the continuity of Kant’s conception of God and his appropriation of his own rationalistic metaphysics
Computing the lower and upper bounds of Laplace eigenvalue problem: by combining conforming and nonconforming finite element methods
This article is devoted to computing the lower and upper bounds of the
Laplace eigenvalue problem. By using the special nonconforming finite elements,
i.e., enriched Crouzeix-Raviart element and extension , we get
the lower bound of the eigenvalue. Additionally, we also use conforming finite
elements to do the postprocessing to get the upper bound of the eigenvalue. The
postprocessing method need only to solve the corresponding source problems and
a small eigenvalue problem if higher order postprocessing method is
implemented. Thus, we can obtain the lower and upper bounds of the eigenvalues
simultaneously by solving eigenvalue problem only once. Some numerical results
are also presented to validate our theoretical analysis.Comment: 19 pages, 4 figure
Pseudo-Hermitian continuous-time quantum walks
In this paper we present a model exhibiting a new type of continuous-time
quantum walk (as a quantum mechanical transport process) on networks, which is
described by a non-Hermitian Hamiltonian possessing a real spectrum. We call it
pseudo-Hermitian continuous-time quantum walk. We introduce a method to obtain
the probability distribution of walk on any vertex and then study a specific
system. We observe that the probability distribution on certain vertices
increases compared to that of the Hermitian case. This formalism makes the
transport process faster and can be useful for search algorithms.Comment: 13 page, 7 figure
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