15,143 research outputs found

    The Optimal Rate of Decline of an Inefficient Industry

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    This paper considers the problem of the optimal time path of contraction of an industry which has been hit by foreign competition, and shows that in general, along the optimal path, a production subsidy is warranted. The optimal subsidy trades off the benefit of unemployment in speeding up the approach to the new long-run equilibrium against the cost of lost output in the ‘inefficient’ industry. The dynamic shadow price of labour in this industry is also derived and shown to be always positive, though below the industry wage rat

    Unbounded-error One-way Classical and Quantum Communication Complexity

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    This paper studies the gap between quantum one-way communication complexity Q(f)Q(f) and its classical counterpart C(f)C(f), under the {\em unbounded-error} setting, i.e., it is enough that the success probability is strictly greater than 1/2. It is proved that for {\em any} (total or partial) Boolean function ff, Q(f)=⌈C(f)/2⌉Q(f)=\lceil C(f)/2 \rceil, i.e., the former is always exactly one half as large as the latter. The result has an application to obtaining (again an exact) bound for the existence of (m,n,p)(m,n,p)-QRAC which is the nn-qubit random access coding that can recover any one of mm original bits with success probability ≥p\geq p. We can prove that (m,n,>1/2)(m,n,>1/2)-QRAC exists if and only if m≤22n−1m\leq 2^{2n}-1. Previously, only the construction of QRAC using one qubit, the existence of (O(n),n,>1/2)(O(n),n,>1/2)-RAC, and the non-existence of (22n,n,>1/2)(2^{2n},n,>1/2)-QRAC were known.Comment: 9 pages. To appear in Proc. ICALP 200

    Unbounded-Error Classical and Quantum Communication Complexity

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    Since the seminal work of Paturi and Simon \cite[FOCS'84 & JCSS'86]{PS86}, the unbounded-error classical communication complexity of a Boolean function has been studied based on the arrangement of points and hyperplanes. Recently, \cite[ICALP'07]{INRY07} found that the unbounded-error {\em quantum} communication complexity in the {\em one-way communication} model can also be investigated using the arrangement, and showed that it is exactly (without a difference of even one qubit) half of the classical one-way communication complexity. In this paper, we extend the arrangement argument to the {\em two-way} and {\em simultaneous message passing} (SMP) models. As a result, we show similarly tight bounds of the unbounded-error two-way/one-way/SMP quantum/classical communication complexities for {\em any} partial/total Boolean function, implying that all of them are equivalent up to a multiplicative constant of four. Moreover, the arrangement argument is also used to show that the gap between {\em weakly} unbounded-error quantum and classical communication complexities is at most a factor of three.Comment: 11 pages. To appear at Proc. ISAAC 200

    The Optimal Rate of Decline of an Inefficient Industry

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    This paper considers the problem of the optimal time path of contraction of an industry which has been hit by foreign competition, and shows that in general, along the optimal path, a production subsidy is warranted. The optimal subsidy trades off the benefit of unemployment in speeding up the approach to the new long-run equilibrium against the cost of lost output in the ‘inefficient’ industry. The dynamic shadow price of labour in this industry is also derived and shown to be always positive, though below the industry wage rate

    The engineering geology of the Nottingham area, UK

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    Nottingham was built near a crossing point on the River Trent in the East Midlands of England. Initially, the City developed on a low sandstone hill close to the north bank of the river, which provided a secure, well-drained location above the marshes that bordered the river. Geologically, Nottingham stands at the boundary between Palaeozoic rocks to the north and west, and Mesozoic and Cainozoic strata to the south and east. The area is underlain by coal-bearing Carboniferous Coal Measures, Permian dolomitic limestones, Permo-Triassic mudstones and weak sandstones, Jurassic clays and Quaternary glacial and alluvial deposits. Artificial deposits, resulting from the social, industrial and mineral extraction activities of the past cover the natural deposits over much of the area. This geological environment has underpinned the economic development of the area through the mining of coal (now largely ceased), oil extraction that was important during the Second World War, brickmaking from clays, alluvial sand and gravel extraction from the Trent Valley and gypsum extraction from the Permo-Triassic mudstones. The Permo-Triassic sandstone is a nationally important aquifer and has also been exploited at the surface and from shallow mines for sand. However, this history of the use and exploitation of mineral deposits has created a number of environmental problems including rising groundwater levels, abandoned mine shafts and mining subsidence, and, within the City itself, the occasional collapse of artificial cavities in the sandstone and contaminated land left by industrial activities. Natural constraints on development include gypsum dissolution, landslides, rockfalls, swell-shrink problems in Jurassic clays and flooding. Occasional minor earthquakes are attributed to movements due to coal mining or natural, deep geological structures. Thus, Nottingham’s geological context remains an important consideration when planning its future regeneration and development

    Paramagnonlike excitations and spin diffusion in magnetic resonance studies of copper oxide superconductors

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    The relaxation function theory for a doped two-dimensional Heisenberg antiferromagnetic system in the paramagnetic state for all wave vectors through the Brillouin zone is presented in view of low frequency response of high-TcT_c copper oxide superconductors. We deduced the regions of long lifetime [T≲400(1−4x)T \lesssim 400(1-4x) K] and "overdamped" [T≳700(1−4x)T \gtrsim 700(1-4x) K] paramagnonlike excitations in the temperature (TT)-doping index (xx) phase diagram from plane oxygen nuclear spin-lattice relaxation rate 17(1/T1)^{17}(1/T_1) data in up to optimally doped La2−x_{2-x}Srx_{x}CuO4_{4} thus providing the regimes for the spin wave concept and the ''overdamped'' mode.Comment: Physical Review B, accepted, in pres

    Fractional Operators, Dirichlet Averages, and Splines

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    Fractional differential and integral operators, Dirichlet averages, and splines of complex order are three seemingly distinct mathematical subject areas addressing different questions and employing different methodologies. It is the purpose of this paper to show that there are deep and interesting relationships between these three areas. First a brief introduction to fractional differential and integral operators defined on Lizorkin spaces is presented and some of their main properties exhibited. This particular approach has the advantage that several definitions of fractional derivatives and integrals coincide. We then introduce Dirichlet averages and extend their definition to an infinite-dimensional setting that is needed to exhibit the relationships to splines of complex order. Finally, we focus on splines of complex order and, in particular, on cardinal B-splines of complex order. The fundamental connections to fractional derivatives and integrals as well as Dirichlet averages are presented

    Violating Displaced Persons Human Rights And Impairing The Quality Of Human Resources

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    Each year wars force several millions of people to leave their homes to join the ranks of displaced persons (DPs). Displaced women and children are particularly vulnerable to risks of physical abuses. The loss in current and future human resource quality caused by abuses suffered by DPs is an extreme version of the well-known brain drain phenomenon. The paper considers the psychological damage inflicted upon DPs, the possible effects of Post-Traumatic Stress Disorder (PTSD) and the consequent damage to human resource quality

    Governance, Civil Conflict, And Refugee Protection In Sub-Saharan Africa: A Primer

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    This paper provides an introduction to the concepts of governance and state weakness, fragility or failure.  Selected indices of performance are presented with an emphasis on Sub-Saharan Africa. As noted by the 2005 UK Commission for Africa “The most extreme breakdown of governance is war.” The paper discusses the concepts and definitions of civil conflict and civil war, and the prevalence of civil war in Sub –Saharan Africa.  Among the costs of civil war are the people who are displaced due to their fear for life amidst the conflict.  If displaced persons exit the country they become refugees. The paper provides an introduction to the evolution of international humanitarian law since World War II to protect non-combatants, including refugees
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