Because ports are considered to be the heart of the maritime transportation system, thereby assessing port performance is necessary for a nation’s development and economic success. This study proposes a novel metric, namely, “_port performance index (PPI)_”, to determine the overall performance and utilization of inland waterway ports based on six criteria,_ port facility, port availability, port economics, port service, port connectivity, and port environment_. Unlike existing literature, which mainly ranks ports based on quantitative factors, this study utilizes a Bayesian (...) Network (BN) model that focuses on both quantitative and qualitative factors to rank a port. The assessment of inland waterway port performance is further analyzed based on different advanced techniques such as sensitivity analysis and belief propagation. Insights drawn from the study show that all the six criteria are necessary to predict PPI. The study also showed that port service has the highest impact while port economics has the lowest impact among the six criteria on PPI for inland waterway ports. (shrink)

Data and metrics play an unmistakably powerful role in today's society. Over the years, their use has expanded to cover almost every sphere of everyday life. This book provides a critical investigation into what we can call a ""metric culture"" in which practices of self-tracking and quantification have become more popular than ever before.

In a number of publications A.N. Prior considered the use of what he called ‘metric tense logic’. This is a tense logic in which the past and future operators P and F have an index representing a temporal distance, so that Pnα means that α was true n -much ago, and Fn α means that α will be true n -much hence. The paper investigates the use of metric predicate tense logic in formalising phenomena ormally treated by such devices as (...) multiple indexing or quantification over times. (shrink)

This paper examines one aspect of the legacy of the Value-Free Ideal in conservation science: the view that measurements and metrics in conservation are value-free epistemic tools detached from ideological, ethical, social, and, generally, non-epistemic considerations. Contrary to this view, I will argue that traditional measurement practices entrenched in conservation are in fact permeated with non-epistemic values. I challenge the received view by revealing three non-epistemic assumptions underlying traditional metrics: 1) a human-environment demarcation, 2) the desirability of a (...) people-free landscape, and 3) the exclusion of cultural diversity from biodiversity. I also draw a connection between arguments for retaining traditional metrics to “scientific colonialism,” exemplified by a fortress conservation model. I conclude by advocating for abandoning the myth of the intrinsic value-freedom of measurement practices and embracing metrics aligned with societal and scientific goals. (shrink)

What has the dispositional analysis of properties and laws (e.g. Molnar, Powers, Oxford University Press, Oxford, 2003; Mumford, Laws in nature, Routledge London, 2004; Bird, Nature’s metaphysics, Clarendon Press, Oxford, 2007) to offer to the scientific understanding of physical properties?—The article provides an answer to this question for the case of spacetime points and their metrical properties in General Relativity. The analysis shows that metrical properties are not ‘powers’, i.e. they cannot be understood as producing the effects of spacetime on (...) matter with metaphysical necessity. Instead they possess categorical characteristics which, in connection with specific laws, explain those effects. Thus, the properties of spacetime do not favor the metaphysics of powers with respect to properties and laws. (shrink)

Metrics shape our social worlds in many and more ways. Everyday quantifications of our preferences, our behaviors and our relationships, alter us and the institutions that we constitute. This essay takes a brief look at the metrics of business ethics through two analytic devices. Representation explains the notion that metrics can capture or demonstrate ethics and performativity explains the notion that metrics can shape or constitute ethics. The analytic distinction between representation and performativity is obscured in (...) practice when metrics become targets, indeed much of the social power of metrics comes from their use as targets. Hence, we should pay attention to the world of practice in which measuring and doing are entangled. However, we should not lose sight of the limitations of measurement and the possibility that there are areas of ethical life best left unmeasured. (shrink)

De Marchi and Lorenzetti :253-261, 2016) have recently argued that in fields where the journal impact factor is not calculated, such as in the humanities, it is key to find other indicators that would allow the relevant community to assess the quality of scholarly journals and the research outputs that are published in them. The authors' suggestion is that information concerning the journal's rejection rate and the number of subscriptions sold is important and should be used for such assessment. The (...) question addressed by the authors is very important, yet their proposed solutions are problematic. Here I point to some of these problems and illustrate them by considering as a case in point the field of philosophy. Specifically, here I argue for four main claims. First, even assuming that IF provides a reliable indicator of the quality of journals for the assessment of research outputs, De Marchi and Lorenzetti have failed to validate their suggested indicators and proxies. Second, it has not been clarified why, in absence of IF, other journal-based metrics that are currently available should not be used. Third, the relationship between IF and rejection rate is more complex than the authors suggest. Fourth, accepting the number of sold subscriptions as a proxy would result in discrimination against open access journals. The upshot of my analysis is that the question of how to assess journals and research outputs in the humanities is still far from resolved. (shrink)

The idea that sentences can be closer or further apart in meaning is highly intuitive. Not only that, it is also a pillar of logic, semantic theory and the philosophy of science, and follows from other commitments about similarity. The present paper proposes a novel way of comparing the ‘distance’ between two pairs of propositions. We define ‘\ is closer in meaning to \ than \ is to \’ and thereby give a precise account of comparative propositional similarity facts. Notably, (...) our definition eschews metric assumptions, which are unrealistic in most applications of interest. (shrink)

The core aims of the Global Health Impact Project include incentivizing pharmaceutical companies for socially conscious production and promoting socially conscious consumption among consumers. Its backbone is a metric that computes the amount of illness burden alleviated by a pharmaceutical drug. This essay aims to assess the connection between values and numbers in the Global Health Impact Project. Specifically, I concentrate on two issues, the anonymity of illness burden and the distribution of health benefits. The former issue asks whether we (...) should treat the illness burden of every person the same. The latter issue asks among whom health benefits should be fairly distributed. Examination of these issues begs for clarification of some of the key concepts of the Global Health Impact Project, such as the definition of essential medicines and the significance of national borders. Although this essay focuses on the two particular metric issues in the Global Health Impact Project, its core argument is applicable to other metrics for ethically motivated initiatives—to construct a metric for an ethically motivated initiative, it is not only important to articulate underlying concepts and values, but it is also important to operationalize them, so they are consistently reflected in the metric. (shrink)

It is shown that for compact metric spaces the following statements are pairwise equivalent: “X is Loeb”, “X is separable”, “X has a we ordered dense subset”, “X is second countable”, and “X has a dense set G = ∪{Gn : n ∈ ω}, ∣Gn∣ < ω, with limn→∞ diam = 0”. Further, it is shown that the statement: “Compact metric spaces are weakly Loeb” is not provable in ZF0 , the Zermelo-Fraenkel set theory without the axiom of regularity, and (...) that the countable axiom of choice for families of finite sets CACfin does not imply the statement “Compact metric spaces are separable”. (shrink)

§ 1. Introduction. In this communication we present some recent results on the classification of Polish metric spaces up to isometry and on the isometry groups of Polish metric spaces. A Polish metric space is a complete separable metric space.Our first goal is to determine the exact complexity of the classification problem of general Polish metric spaces up to isometry. This work was motivated by a paper of Vershik [1998], where he remarks : “The classification of Polish spaces up to (...) isometry is an enormous task. More precisely, this classification is not ‘smooth’ in the modern terminology.” Our Theorem 2.1 below quantifies precisely the enormity of this task.After doing this, we turn to special classes of Polish metric spaces and investigate the classification problems associated with them. Note that these classification problems are in principle no more complicated than the general one above. However, the determination of their exact complexity is not necessarily easier.The investigation of the classification problems naturally leads to some interesting results on the groups of isometries of Polish metric spaces. We shall also present these results below.The rest of this section is devoted to an introduction of some basic ideas of a theory of complexity for classification problems, which will help to put our results in perspective. Detailed expositions of this general theory can be found, e.g., in Hjorth [2000], Kechris [1999], [2001]. (shrink)

We prove that each ∀1 free amalgamation class K over a finite relational language L admits a countable generic structure M isometrically embedding all countable structuresin K relative to a fixed metric. We expand L by infinitely many binary predicates expressingdistance, and prove that the resulting expansion of K has a model companion axiomatizedby the first-order theory of M. The model companion is non-finitely axiomatizable, evenover a strong form of the axiom scheme of infinity.

We classify countable metrically homogeneous graphs of diameter 3.

We classify countable metrically homogeneous graphs of diameter 3.

The paper introduces a broad family of metrics applicable to finite and countably infinite strings, or, by extension, to formal structures serving as semantics for countable languages. The main focus is on applications to sets of pointed Kripke models, a semantics for modal logics. For the resulting metric spaces, the paper classifies topological properties including which metrics are topologically equivalent, providing sufficient conditions for compactness, characterizing clopen sets and isolated points, and characterizing the metrical topologies by a concept (...) of logical convergence. We then apply the approach to maps from dynamic epistemic logic, showing that product updates with action models yield continuous maps, hence allowing for an interpretation of the iterated updates as discrete time dynamical systems. (shrink)

Citation metrics are statistical measures of scientific output that draw on citation indexes. They purport to capture the impact of scientific articles and the journals in which they appear. As evaluative tools they are mostly used in the natural sciences, but they are also acquiring an important role in the humanities. While the strengths and weaknesses of citation metrics are extensively debated in a variety of fields, they have only recently started attracting attention in the philosophy of science. (...) This paper takes a further step in this direction and presents an analysis of citation metrics from the perspective of a Kuhnian model for the development of science. To do so, it assesses the argument made against the use of citation metrics for scientific research by Gillies (2008). According to Gillies, citations metrics tend to over-protect normal science at the expenses of revolutionary science–in other words, reinforce the status quo rather than supporting innovations and breakthroughs. Unlike Gillies, this paper focuses on the context of normal science and shows that citation metrics can in fact arbitrarily hinder its development when they do not take field-specific differences into account. In light of this, the paper cautions against their use for evaluative purposes. To argue for this conclusion, the paper shows that citation metrics fail to “carve science at its joints” and thus cannot be relied upon as indicators of scientific quality that can support the development of normal science. (shrink)

The issue of plagiarism—claiming credit for work that is not one’s own, rightly, continues to cause concern in the academic community. An analysis is presented that shows the effects that may arise from metrics-based assessments of research, when credit for an author’s outputs (chiefly publications) is given to an institution that did not support the research but which subsequently employs the author. The incentives for what is termed here “institutional plagiarism” are demonstrated with reference to the UK Research Assessment (...) Exercise in which submitting units of assessment are shown in some instances to derive around twice the credit for papers produced elsewhere by new recruits, compared to papers produced ‘in-house’. (shrink)

In the mid twenty-tens, many major food companies committed to sustainably source their priority ingredients, including North American commodity crops. With deadlines set for the decade’s end, companies joined multi-stakeholder initiatives and developed standards, metrics, and other assessment tools to help them track and drive progress. In short, they embarked on the sort of corporate supply chain governance that agri-food scholars have long studied. But how would this governance happen, especially in the commodity supply chains where companies knew and (...) controlled little about upstream production? Treating supply chain governance as not just a corporate undertaking but also the work of mid-level sustainability managers, this paper examines the practical skills and knowledge, or mētis, employed by managers in their efforts to win the support of colleagues, farmers, and other supply chain actors. This analysis provides insight into how and why food companies’ approaches to governing agricultural sustainability have changed since they set their 2020 sourcing goals. More broadly, it highlights the contingent nature of their governance. (shrink)

There is a long tradition in economics of evaluating social arrangements by the extent to which individuals' preferences are satisfied. This is the tradition of welfarism, which has developed from nineteenth-century utilitarianism. Increasingly, however, the presumption that preference-satisfaction is the appropriate standard for evaluating social arrangements is being challenged by an alternative view: that we should focus on the set of opportunities open to each individual.

General relativity poses serious problems for counterfactual propositions peculiar to it as a physical theory. Because these problems arise solely from the dynamical nature of spacetime geometry, they are shared by all schools of thought on how counterfactuals should be interpreted and understood. Given the role of counterfactuals in the characterization of, inter alia, many accounts of scientific laws, theory confirmation and causation, general relativity once again presents us with idiosyncratic puzzles any attempt to analyze and understand the nature of (...) scientific knowledge must face. (shrink)

Any theory of health justice requires an account of what areas of social life are important enough to be of public concern. What are the goods that ought to be provided as a matter of justice? This is what I will call the metric problem. The capabilities approach puts forward a particular solution to this problem. In this article I will discuss some issues of such an approach in relation to Sridhar Venkatapuram's well-known theory. Another problem I examine is how (...) to determine a threshold of provision within a theory of justice. What is enough in terms of health justice? I argue that we need such a threshold to avoid healthism, the expansion of the pursuit of health over and above the treatment and prevention of disease. This is an especially pertinent problem in public health, which is also the context of Venkatapuram's theory. (shrink)

We study conditions for a topological space to be metrizable, properties of metrizable spaces, and the role the axiom of choice plays in these matters.

What kind of Theory of Music and Theory of Metric was taught to the young Pindar or the young Sophocles? So far are we from an answer to this question that we do not even know how far extra study was necessary, or usual, for the professional poet as compared with the ordinary educated Greek citizen. The interdependence of music and metric in lyric poetry gave complexity to the word-rhythms but kept the study of music, the subordinate partner, theoretically simple. (...) Doubtless by the time the young poet had learnt by heart the words of past masters of lyric verse, sung or accompanied them on the lyre, and danced them in choir or κ⋯μος, he had absorbed by practice and somewhat rule-of-thumb methods of training a great deal of the τ⋯χενη which his calling would require. He would have to learn, in common with the χοροδιδ⋯σκαλος, how to read and write a simple score, and so he must know the symbols of pitch in such scales as were then in use. The notation of arsis and thesis may have been required too, and if we knew that this was so, and how he was taught to apply it, we might be in a much better position to assess the kind of theory he learnt. But of one thing we may be sure: genius apart, it was his practical training, as performer and spectator, rather than theoretical teaching which gave his ear its cunning and technical skill to compose new rhythms. (shrink)

Info-metrics is a framework for rational inference based on insufficient information. The complete info-metric framework, accompanied with many interdisciplinary examples and case studies, as well as graphical representations of the theory appear in the new book “Foundations of Info-Metrics: Modeling, Inference and Imperfect Information,” Oxford University Press, 2018. In this commentary, I describe that framework in general terms, demonstrate some of the ideas via simple examples, and provide arguments for using it to transform information into useful knowledge.

This work concerns constructive aspects of measure theory. By considering metric completions of Boolean algebras – an approach first suggested by Kolmogorov – one can give a very simple construction of e.g. the Lebesgue measure on the unit interval. The integration spaces of Bishop and Cheng turn out to give examples of such Boolean algebras. We analyse next the notion of Borel subsets. We show that the algebra of such subsets can be characterised in a pointfree and constructive way by (...) an initiality condition. We then use our work to define in a purely inductive way the measure of Borel subsets. (shrink)

We show that the set of points of an overt closed subspace of a metric completion of a Bishop-locally compact metric space is located. Consequently, if the subspace is, moreover, compact, then its collection of points is Bishop-compact. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In this study a combination of computer tools for coupling and virtual screening is detailed, in 108 active molecules and 3620 decoys to find stabilizers for G quadruplex. To have more precise results, combinations of coupling programs with fifteen energy scoring functions were applied. The validation and evaluation of the metrics was done with the CompScore genetic algorithm. The results showed an increase in BEDROC and EF of 50% compared to other strategies, as well as reflecting early recognition of (...) active molecules. From these results it is possible to work with the molecules that showed a good early recognition and evaluate their effect as G4 stabilizers. This ensures more efficient and accurate results in the preclinical stage for the development of anticancer drugs. Keywords: Enrichment metrics; telomere; G quadruplex ; CompScore. References [1]M. Porru, P. Zizza, M. Franceschin, C. Leonetti and A. Biroccio. «EMICORON: A multi-targeting G4 ligand with a promising preclinical profile» 2017. Biochimica et Biophysica Acta - General Subjects, 1861, 1362–1370. [Online]. Available: https://doi.org/10.1007/s00294-018-0836-6. [2]K. Tomita. «How long does telomerase extend telomeres? Regulation of telomerase release and telomere length homeostasis». Current Genetics, 64, 1177–1181. 2018. [Online]. Available: https://doi.org/10.1016/j.bbagen. 2016.11.010. [3]M. Jafri, S. Ansari, M. Alqahtani and J. Shay. «Roles of telomeres and telomerase in cancer, and advances in telomerase-targeted therapies. Genome Medicine., 2016. [Online]. Available: https://doi.org/10.3390/ijms19020482. [4]J. Huppert and S. Balasubramanian. «G-quadruplexes in promoters throughout the human genome». 35, 406–413. 2007. [Online]. Available: https://doi.org/10.1016/j.bbapap.2017.06.012. [5]S. Joy, Vijayakumar, S. Choi and H. Sunhye. «Role of computer-aided drug design in modern drug discovery». Archives of Pharmacal Research. 2015. [Online]. Available: https://doi.org/10.1007/s12272-015-0640-5. [6]S. Asamitsu, S. Obata, Z. Yu, T. Bando and H. Sugiyama. «Recent Progress of Targeted G-Quadruplex-Preferred Ligands Toward Cancer Therapy». Molecules, 24, 429. 2019. [En línea]. Available: https://doi.org/10.3390/molecules24030429. [7]R. Monsen and J. Trent. «Biochimie G-quadruplex virtual drug screening : A review». Biochimie, 152, 134–148. 2018. [Online]. Available: https://doi.org/10.1039/c9cc06748e. [8]J. Beauvarlet, P. Bensadoun, E. Darbo, G. Labrunie, E. Richard, I. Draskovic and M. Djavaheri-mergny. «Modulation of the ATM / autophagy pathway by a G-quadruplex ligand tips the balance between senescence and apoptosis in cancer cells». 1–18. 2019. [Online]. Available: https://doi.org/10.1093/nar/gkz095. [9].Z. Crees, J. Girard, Z. Rios, G. Botting, K. Harrington and C. Shearrow. « Oligonucleotides and G-quadruplex stabilizers: targeting telomeres and telomerase in cancer therapy».2014. [Online]. Available: https://doi.org/10.2174/1381612820666140630100702. [10].M. Meier, A. Moya-torres, N. Krahn, M. Mcdougall, L. Orriss, E. Mcrae and T. Patel. «Structure and hydrodynamics of a DNA Gquadruplex with a cytosine bulge»., 1–13. 2018. [Online]. Available: https://doi.org/10.1093/nar/gky307. (shrink)

Fix an integer $r \ge 3$. We consider metric spaces on n points such that the distance between any two points lies in $\left\{ {1, \ldots,r} \right\}$. Our main result describes their approximate structure for large n. As a consequence, we show that the number of these metric spaces is $\left\lceil {{{r + 1} \over 2}} \right\rceil ^{\left + o\left}.$Related results in the continuous setting have recently been proved by Kozma, Meyerovitch, Peled, and Samotij [34]. When r is even, our (...) structural characterization is more precise and implies that almost all such metric spaces have all distances at least $r/2$. As an easy consequence, when r is even, we improve the error term above from $o\left$ to $o\left$, and also show a labeled first-order 0-1 law in the language ${\cal L}_r $, consisting of r binary relations, one for each element of $[r]$. In particular, we show the almost sure theory T is the theory of the Fraïssé limit of the class of all finite simple complete edge-colored graphs with edge colors in $\left\{ {r/2, \ldots,r} \right\}$.Our work can be viewed as an extension of a long line of research in extremal combinatorics to the colored setting, as well as an addition to the collection of known structures that admit logical 0-1 laws. (shrink)

I Assume that in Latin there was a stress accent which, in the time of Lucretius, was governed by the well-known ‘law of the penultimate’; also that in Latin poetry, although the metre is determined by the quantity of the syllable, nevertheless the stress accent must not be ignored. In fact, the inter-relation of the ictus of the quantitative metre with the stress accent is a most important factor in determining the rhythm of the verse. It is well known that (...) in the Latin hexameter special importance was attached to the coincidence of ictus and accent in the fifth and sixth feet, so as to secure a characteristic and definite ending to the line. But the coincidence or clash of ictus and accent has its effect in every foot, although to a less extent. Particularly in the fourth foot is it important. There is an obvious difference between a line in which stress accent reinforces the ictus in the fourth, fifth, and sixth feet, and a line in which conflict occurs between ictus and accent in the fourth foot. W. F. J . Knight refers to these lines as homodyned and heterodyned. Each foot of the hexameter could be examined for the effect of homodyne and heterodyne; I am limiting this discussion to the fourth foot. In classifying fourth feet as homodyned or heterodyned, I have described as homodyned a foot in which a stress accent coincides with the ictus; all other feet are heterodyned. It must be realized, however, that there are possible varieties of homodyned fourth feet. They may be spondaic or dactylic; they may be caused by the overlap of the last two syllables of a polysyllabic word, or they may consist of a single word or two words. There is a great difference of metrical effect. Heterodyned lines may again be differentiated between those which contain a stress accent clashing with the ictus, and those in which there is no stress accent at all. (shrink)

£ The existence of a model for a logic program is generally established by lattice-theoretic arguments. We present three examples to show that metric methods can often be used instead, generally in a direct, straightforward way. One example is a game program, which is not stratified or locally stratified, but which has a unique supported model whose existence is easily established using metric methods. The second example is a program without a unique supported model, but having a part that is (...) ‘well-behaved.’ The third example is a program in which one part depends on another, illustrating how modularity might be treated metrically. Finally we use ideas from this third example to prove a general result from [3]. The intention in presenting these examples and the theorem is to stimulate interest in.. (shrink)

Text, interpretation and metre present a tangled problem in this threnody, and the solutions of editors differ widely. The chief function of detailed metrical study in such corrupt passages of lyric is to weight the scales in favour of—or more often against—certain methods of handling the text. The positive results of this present attempt to apply metrical criteria are necessarily modest and tentative; negatively they are, I think, sometimes decisive.

I Am not proposing in this essay to treat at length and in detail of the metric of other lyric poets. In most cases questions of metre are intimately involved with questions of text, into which so many other considerations enter that in dealing with them proportion would be lost, while metrical analysis of such material would still remain largely speculative. What follows is therefore little more than a general account of the principles of composition which these poets appear to (...) me to follow; I have, however, indicated a few passages where emendations made purely on metrical grounds and widely accepted seem to me, in the absence of responsion, based on too ready a desire to reduce all poems to the best-known formulas of versification. (shrink)

What kind of Theory of Music and Theory of Metric was taught to the young Pindar or the young Sophocles? So far are we from an answer to this question that we do not even know how far extra study was necessary, or usual, for the professional poet as compared with the ordinary educated Greek citizen. The interdependence of music and metric in lyric poetry gave complexity to the word-rhythms but kept the study of music, the subordinate partner, theoretically simple. (...) Doubtless by the time the young poet had learnt by heart the words of past masters of lyric verse, sung or accompanied them on the lyre, and danced them in choir or κμος, he had absorbed by practice and somewhat rule-of-thumb methods of training a great deal of the τχενη which his calling would require. He would have to learn, in common with the χοροδιδσκαλος, how to read and write a simple score, and so he must know the symbols of pitch in such scales as were then in use. The notation of arsis and thesis may have been required too, and if we knew that this was so, and how he was taught to apply it, we might be in a much better position to assess the kind of theory he learnt. But of one thing we may be sure: genius apart, it was his practical training, as performer and spectator, rather than theoretical teaching which gave his ear its cunning and technical skill to compose new rhythms. (shrink)

I Am not proposing in this essay to treat at length and in detail of the metric of other lyric poets. In most cases questions of metre are intimately involved with questions of text, into which so many other considerations enter that in dealing with them proportion would be lost, while metrical analysis of such material would still remain largely speculative. What follows is therefore little more than a general account of the principles of composition which these poets appear to (...) me to follow; I have, however, indicated a few passages where emendations made purely on metrical grounds and widely accepted seem to me, in the absence of responsion, based on too ready a desire to reduce all poems to the best-known formulas of versification. (shrink)

If ${\mathfrak {F}}$ is a type-definable family of commensurable subsets, subgroups or subvector spaces in a metric structure, then there is an invariant subset, subgroup or subvector space commensurable with ${\mathfrak {F}}$. This in particular applies to type-definable or hyper-definable objects in a classical first-order structure.

We introduce a new Turing machine based concept of time complexity for functions on computable metric spaces. It generalizes the ordinary complexity of word functions and the complexity of real functions studied by Ko [19] et al. Although this definition of TIME as the maximum of a generally infinite family of numbers looks straightforward, at first glance, examples for which this maximum exists seem to be very rare. It is the main purpose of this paper to prove that, nevertheless, the (...) definition has a large number of important applications. Using the framework of TTE [40], we introduce computable metric spaces and computability on the compact subsets. We prove that every computable metric space has a c-proper c-admissible representation. We prove that Turing machine time complexity of a function computable relative to c-admissible c-proper representations has a computable bound on every computable compact subset. We prove that computably compact computable metric spaces have concise c-proper c-admissible representations and show by examples that many canonical representations are of this kind. Finally, we compare our definition with a similar one by Labhalla et al. [22]. Several examples illustrate the concepts. By these results natural and realistic definitions of computational complexity are now available for a variety of numerical problems such as image processing, integration, continuous Fourier transform or wave propagation. (shrink)

This essay defines Maoism as an experiment in intimate governance and an attempt—albeit a failed one—to dismantle the divide between political leaders and ordinary people. The Communist Party’s claim to intimacy with the people needs to be constantly reenacted in the relationship between party cadres and ordinary citizens––a cadre’s gestures, habits, and attitudes are magnified and scrutinized under the lens of party legitimacy. The special privileges (tequan, 特权) of party leaders are what I call metrics of exceptionality, which separate (...) the party from the people. The promise to govern on the basis of intimacy with the people did not eradicate ruling class entitlements and arrogance but delegitimized them and opened them up to public scrutiny. Although the process of eradicating privileges was always several steps behind their elaboration and intensification, the former was a normative goal that shaped how ordinary citizens perceived and interacted with party cadres. This dual movement in opposing directions still constitutes the fundamental contradiction of China’s political system as seen from within. This essay revisits and examines crucial historical junctures in the People’s Republic of China as framed by popular contestations of special privilege. The fact that in the post-Mao period, party leaders still speak in the language of intimacy, proximity, and distance indicates the aesthetic importance of this relationship in party ideology, despite public complaints regarding its absence. Even when intimacy as a political mode of communication is able to communicate nothing but its own failure, the proximity between the party and the people takes center stage as the aesthetic foundation of party legitimacy. (shrink)

We introduce a new way of defining metric temporal logic on a real-numbers flow of time. The idea is based on having semantics which allow us to refer to a single universal clock of arbitrary precision in order to impose metric constraints. This gives us a new metric temporal logic which is very expressive, is natural to use, can be applied in very general situations, affords a wide range of useful abbreviations and operators, has a PSPACE decision procedure, and has (...) the promise of being amenable to standard reasoning techniques. Thus it has many advantages over the existing metric temporal logics. We provide a decision procedure via conversion to a non-metric temporal logic, hence doing metric reasoning with no clocks. (shrink)

We study Polish spaces for which a set of possible distances $A \subseteq R^+$ is fixed in advance. We determine, depending on the properties of A, the complexity of the collection of all Polish metric spaces with distances in A, obtaining also example of sets in some Wadge classes where not many natural examples are known. Moreover we describe the properties that A must have in order that all Polish spaces with distances in that set belong to a given class, (...) such as zero-dimensional, locally compact, etc. These results lead us to give a fairly complete description of the complexity, with respect to Borel reducibility and again depending on the properties of A, of the relations of isometry and isometric embeddability between these Polish spaces. (shrink)

We show that metric abstract elementary classes are, in the sense of [15], coherent accessible categories with directed colimits, with concrete ℵ1-directed colimits and concrete monomorphisms. More broadly, we define a notion of κ-concrete AEC—an AEC-like category in which only the κ-directed colimits need be concrete—and develop the theory of such categories, beginning with a category-theoretic analogue of Shelah’s Presentation Theorem and a proof of the existence of an Ehrenfeucht–Mostowski functor in case the category is large. For mAECs in particular, (...) arguments refining those in [15] yield a proof that any categorical mAEC is μ-d-stable in many cardinals below the categoricity cardinal. (shrink)