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  1. Charles M. Harris (2012). Badness and Jump Inversion in the Enumeration Degrees. Archive for Mathematical Logic 51 (3-4):373-406.
    This paper continues the investigation into the relationship between good approximations and jump inversion initiated by Griffith. Firstly it is shown that there is a ${\Pi^{0}_{2}}$ set A whose enumeration degree a is bad—i.e. such that no set ${X \in a}$ is good approximable—and whose complement ${\overline{A}}$ has lowest possible jump, in other words is low2. This also ensures that the degrees y ≤ a only contain ${\Delta^{0}_{3}}$ sets and thus yields a tight lower bound for the complexity of both (...)
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  2. Charles M. Harris (2011). On the Jump Classes of Noncuppable Enumeration Degrees. Journal of Symbolic Logic 76 (1):177 - 197.
    We prove that for every ${\mathrm{\Sigma }}_{2}^{0}$ enumeration degree b there exists a noncuppable ${\mathrm{\Sigma }}_{2}^{0}$ degree a > 0 e such that b′ ≤ e a′ and a″ ≤ e b″. This allows us to deduce, from results on the high/low jump hierarchy in the local Turing degrees and the jump preserving properties of the standard embedding l: D T → D e , that there exist ${\mathrm{\Sigma }}_{2}^{0}$ noncuppable enumeration degrees at every possible—i.e., above low₁—level of the high/low (...)
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  3. Colleen Murphy, Paolo Gardoni & Charles Harris (2011). Classification and Moral Evaluation of Uncertainties in Engineering Modeling. Science and Engineering Ethics 17 (3):553-570.
    Engineers must deal with risks and uncertainties as a part of their professional work and, in particular, uncertainties are inherent to engineering models. Models play a central role in engineering. Models often represent an abstract and idealized version of the mathematical properties of a target. Using models, engineers can investigate and acquire understanding of how an object or phenomenon will perform under specified conditions. This paper defines the different stages of the modeling process in engineering, classifies the various sources of (...)
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  4. Charles M. Harris (2010). Goodness in the Enumeration and Singleton Degrees. Archive for Mathematical Logic 49 (6):673-691.
    We investigate and extend the notion of a good approximation with respect to the enumeration ${({\mathcal D}_{\rm e})}$ and singleton ${({\mathcal D}_{\rm s})}$ degrees. We refine two results by Griffith, on the inversion of the jump of sets with a good approximation, and we consider the relation between the double jump and index sets, in the context of enumeration reducibility. We study partial order embeddings ${\iota_s}$ and ${\hat{\iota}_s}$ of, respectively, ${{\mathcal D}_{\rm e}}$ and ${{\mathcal D}_{\rm T}}$ (the Turing degrees) into (...)
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  5. Charles E. Harris (2008). The Good Engineer: Giving Virtue its Due in Engineering Ethics. Science and Engineering Ethics 14 (2):153-164.
    During the past few decades, engineering ethics has been oriented towards protecting the public from professional misconduct by engineers and from the harmful effects of technology. This “preventive ethics” project has been accomplished primarily by means of the promulgation of negative rules. However, some aspects of engineering professionalism, such as (1) sensitivity to risk (2) awareness of the social context of technology, (3) respect for nature, and (4) commitment to the public good, cannot be adequately accounted for in terms of (...)
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  6. Charles M. Harris (2007). On the Symmetric Enumeration Degrees. Notre Dame Journal of Formal Logic 48 (2):175-204.
    A set A is symmetric enumeration (se-) reducible to a set B (A ≤\sb se B) if A is enumeration reducible to B and \barA is enumeration reducible to \barB. This reducibility gives rise to a degree structure (D\sb se) whose least element is the class of computable sets. We give a classification of ≤\sb se in terms of other standard reducibilities and we show that the natural embedding of the Turing degrees (D\sb T) into the enumeration degrees (D\sb e) (...)
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  7. Charles E. Harris (2005). Reflective Equilibrium as a Theory of Moral Change. Southwest Philosophy Review 21 (2):67-82.
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  8. Charles E. Harris (2001). Commentary On: “The Greening of Engineers: A Cross-Cultural Experience” (A. Ansari). Science and Engineering Ethics 7 (1):117-119.
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  9. Charles E. Harris (1998). Engineering Responsibilities in Lesser-Developed Nations: The Welfare Requirement. Science and Engineering Ethics 4 (3):321-331.
    Increasing numbers of engineers from developed countries are employed during some part of their careers in lesser-developed nations (LDN’s), or they may design products for use in LDN’s. Yet determining the implications of professional engineering codes for engineers’ conduct in such settings can be difficult. Conditions are often substantially different from those in developed countries, where the codes were formulated. In this paper I explore the implications of what I call the “welfare requirement” in engineering codes for professional engineering conduct (...)
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  10. Charles E. Harris Jr (1974). Rawls on Justification in Ethics. Southwestern Journal of Philosophy 5 (1):135-143.
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  11. Charles S. Harris & Ralph Norman Haber (1963). Selective Attention and Coding in Visual Perception. Journal of Experimental Psychology 65 (4):328.
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  12. Charles Harris (1927). First Steps in the Philosophy of Religion. London, Student Christian Movement.
     
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  13. Charles Reginald Schiller Harris (1927). Duns Scotus. Oxford, the Clarendon Press.
    --I. The place of Duns Scotus in medieval thought.--II. The philosophical doctrines of Duns Scotus.
     
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