10,046 research outputs found
Physical Simulation of Inarticulate Robots
In this note we study the structure and the behavior of inarticulate robots.
We introduce a robot that moves by successive revolvings. The robot's structure
is analyzed, simulated and discussed in detail
Ambulance service operational improvement
This document is the accepted manuscript version of a Published Work that appeared in final form in International Paramedic Practice copyright © MA Healthcare, after peer review and technical editing by the Publisher. To access the final edited version see http://www.internationaljpp.com/cgi-bin/go.pl/library/article.cgi?uid=100396;article=IPP_3_3_61_63Since the start of industrialisation in the beginning of the previous century, processes, and technology have evolved drastically. Technology that had been developed for a specific application was found to open new horizons in other domains. A good example is the use of sonar technology on military submarines which eventually found medical applications in medical imaging (Oakley, 1986). The paramedic profession is still considered to be a relatively young profession, and although the clinical scope of practice of ambulance staff has widened there have been few noticeable and significant changes in the way Ambulance Services operate as public service providers. There is, however, great variation in the way pre-hospital emergency care provision is delivered and organised from country to country due for example to historical, cultural, financial, and geographical factors. Other industries are significantly more driven by profit, hence efficiency and reliability are aspects that have a direct and measurable financial impact and it acts as a driver for further developments.Peer reviewedSubmitted Versio
Kitaev's Z_d-Codes Threshold Estimates
We study the quantum error correction threshold of Kitaev's toric code over
the group Z_d subject to a generalized bit-flip noise. This problem requires
novel decoding techniques, and for this purpose we generalize the
renormalization group method we previously introduced for Z_2 topological
codes.Comment: 5 pages, 5 figure
Making and breaking monetary policy rules: the experience of African countries
This paper analyses the experience with rule-based monetary policy in African countries which have participated in monetary unions (CFA Franc Zone, Eastern African Currency Board and Rand Monetary Area). We show that African countries have generally lacked the domestic political institutions which would allow individual governments to tie their hands by establishing such rules. Monetary unions have proved to be an alternative possibility for credible commitment to sound macroeconomic policies, but only in cases where exit from a union is made costly by the provision of side-payments (or sanctions) in other areas of regional co-operation, and only when governance structures have been designed so as to maximise chances for the enforcement of monetary rules. We conclude by making suggestions about the design of African monetary unions.
Improving Policy Credibility: Is There a Case for African Monetary Unions?
This paper analyses the experience with monetary policy in African countries which have participated in rule-based international monetary arrangements (CFA Franc Zone, Eastern African Currency Board and Rand Monetary Area). It argues that African countries have generally lack the political institutions necessary for governments to credibly commit through domestic institutions (exchange rate pegs or independent central banks). For such countries, monetary unions can provide an alternative source of credible commitment to sound macroeconomic policies, but only when exit from a union is made costly by the existence of parallel regional accords, and only when governance structures of monetary unions have been designed so as to maximise chances for the enforcement of monetary rules.
Fully polynomial FPT algorithms for some classes of bounded clique-width graphs
Parameterized complexity theory has enabled a refined classification of the
difficulty of NP-hard optimization problems on graphs with respect to key
structural properties, and so to a better understanding of their true
difficulties. More recently, hardness results for problems in P were achieved
using reasonable complexity theoretic assumptions such as: Strong Exponential
Time Hypothesis (SETH), 3SUM and All-Pairs Shortest-Paths (APSP). According to
these assumptions, many graph theoretic problems do not admit truly
subquadratic algorithms, nor even truly subcubic algorithms (Williams and
Williams, FOCS 2010 and Abboud, Grandoni, Williams, SODA 2015). A central
technique used to tackle the difficulty of the above mentioned problems is
fixed-parameter algorithms for polynomial-time problems with polynomial
dependency in the fixed parameter (P-FPT). This technique was introduced by
Abboud, Williams and Wang in SODA 2016 and continued by Husfeldt (IPEC 2016)
and Fomin et al. (SODA 2017), using the treewidth as a parameter. Applying this
technique to clique-width, another important graph parameter, remained to be
done. In this paper we study several graph theoretic problems for which
hardness results exist such as cycle problems (triangle detection, triangle
counting, girth, diameter), distance problems (diameter, eccentricities, Gromov
hyperbolicity, betweenness centrality) and maximum matching. We provide
hardness results and fully polynomial FPT algorithms, using clique-width and
some of its upper-bounds as parameters (split-width, modular-width and
-sparseness). We believe that our most important result is an -time algorithm for computing a maximum matching where
is either the modular-width or the -sparseness. The latter generalizes
many algorithms that have been introduced so far for specific subclasses such
as cographs, -lite graphs, -extendible graphs and -tidy
graphs. Our algorithms are based on preprocessing methods using modular
decomposition, split decomposition and primeval decomposition. Thus they can
also be generalized to some graph classes with unbounded clique-width
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