791 research outputs found
Reinforcement learning for Order Acceptance on a shared resource
Order acceptance (OA) is one of the main functions in business control. Basically, OA involves for each order a reject/accept decision. Always accepting an order when capacity is available could disable the system to accept more convenient orders in the future with opportunity losses as a consequence. Another important aspect is the availability of information to the decision-maker. We use the stochastic modeling approach, Markov decision theory and learning methods from artificial intelligence to find decision policies, even under uncertain information. Reinforcement learning (RL) is a quite new approach in OA. It is capable of learning both the decision policy and incomplete information, simultaneously. It is shown here that RL works well compared with heuristics. Finding good heuristics in a complex situation is a delicate art. It is demonstrated that a RL trained agent can be used to support the detection of good heuristics
Investment provisions in trade and investment treaties: the need for reform
This repository item contains a policy brief from the Boston University Global Economic Governance Initiative. The Global Economic Governance Initiative (GEGI) is a research program of the Center for Finance, Law & Policy, the Frederick S. Pardee Center for the Study of the Longer-Range Future, and the Frederick S. Pardee School of Global Studies. It was founded in 2008 to advance policy-relevant knowledge about governance for financial stability, human development, and the environment.Nations of the world are currently negotiating a
variety of significant trade and investment treaties
that cover upwards of eighty percent of the world
economy. The Trans-Pacific Partnership (TPP)
would further integrate a number of Pacific-Rim
nations; the Trans-Atlantic Trade and Investment
Partnership (TTIP) would be a treaty between
the United States and European countries. The
United States and others are also negotiating major
bilateral investment treaties (BITs) with China and
India
Establishing cost-effectiveness of genetic targeting of cancer therapies
The clinical benefit of a new genomic instrument, the 70-gene signature for breast cancer patients, is being evaluated in a randomised clinical trial. The early, controlled implementation process is supported by a Constructive Technology Assessment to help decision-making in an uncertain time of development
Establishing cost-effectiveness of genetic targeting of cancer therapies\ud
The clinical benefit of a new genomic instrument, the 70-gene signature\ud
for breast cancer patients, is being evaluated in a randomised clinical\ud
trial. The early, controlled implementation process is supported by a\ud
Constructive Technology Assessment to help decision-making in an\ud
uncertain time of developmen
On the Divergence-Free Condition in Godunov-Type Schemes for Ideal Magnetohydrodynamics: the Upwind Constrained Transport Method
We present a general framework to design Godunov-type schemes for
multidimensional ideal magnetohydrodynamic (MHD) systems, having the
divergence-free relation and the related properties of the magnetic field B as
built-in conditions. Our approach mostly relies on the 'Constrained Transport'
(CT) discretization technique for the magnetic field components, originally
developed for the linear induction equation, which assures div(B)=0 and its
preservation in time to within machine accuracy in a finite-volume setting. We
show that the CT formalism, when fully exploited, can be used as a general
guideline to design the reconstruction procedures of the B vector field, to
adapt standard upwind procedures for the momentum and energy equations,
avoiding the onset of numerical monopoles of O(1) size, and to formulate
approximate Riemann solvers for the induction equation. This general framework
will be named here 'Upwind Constrained Transport' (UCT). To demonstrate the
versatility of our method, we apply it to a variety of schemes, which are
finally validated numerically and compared: a novel implementation for the MHD
case of the second order Roe-type positive scheme by Liu and Lax (J. Comp.
Fluid Dynam. 5, 133, 1996), and both the second and third order versions of a
central-type MHD scheme presented by Londrillo and Del Zanna (Astrophys. J.
530, 508, 2000), where the basic UCT strategies have been first outlined
On the Nonlinearity of Modern Shock-Capturing Schemes
The development is reviewed of shock capturing methods, paying special attention to the increasing nonlinearity in the design of numerical schemes. The nature is studies of this nonlinearity and its relation to upwind differencing is examined. This nonlinearity of the modern shock capturing methods is essential, in the sense that linear analysis is not justified and may lead to wrong conclusions. Examples to demonstrate this point are given
High Order Upwind Schemes for Multidimensional Magnetohydrodynamics
A general method for constructing high order upwind schemes for
multidimensional magnetohydrodynamics (MHD), having as a main built-in
condition the divergence-free constraint \divb=0 for the magnetic field
vector \bb, is proposed. The suggested procedure is based on {\em
consistency} arguments, by taking into account the specific operator structure
of MHD equations with respect to the reference Euler equations of gas-dynamics.
This approach leads in a natural way to a staggered representation of the \bb
field numerical data where the divergence-free condition in the cell-averaged
form, corresponding to second order accurate numerical derivatives, is exactly
fulfilled. To extend this property to higher order schemes, we then give
general prescriptions to satisfy a order accurate \divb=0
relation for any numerical \bb field having a order interpolation
accuracy. Consistency arguments lead also to a proper formulation of the upwind
procedures needed to integrate the induction equations, assuring the exact
conservation in time of the divergence-free condition and the related
continuity properties for the \bb vector components. As an application, a
third order code to simulate multidimensional MHD flows of astrophysical
interest is developed using ENO-based reconstruction algorithms. Several test
problems to illustrate and validate the proposed approach are finally
presented.Comment: 34 pages, including 14 figure
The future of North American trade policy: lessons from NAFTA
This repository item contains a single issue of the Pardee Center Task Force Reports, a publication series that began publishing in 2009 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future.This Task Force Report written by an international group of trade policy experts calls for significant reforms to address adverse economic, environmental, labor and societal impacts created by the 1994 North American Free Trade Agreement (NAFTA).
The report is intended to contribute to the discussion and decisions stemming from ongoing reviews of proposed reforms to NAFTA as well as to help shape future trade agreements. It offers detailed proposals on topics including services, manufacturing, agriculture, investment, intellectual property, labor, environment, and migration.
Fifteen years after NAFTA was enacted, there is widespread agreement that the trade treaty among the United States, Canada and Mexico has fallen short of its stated goals. While proponents credit the agreement with stimulating the flow of goods, services, and investment among the North American countries, critics in all three countries argue that this has not brought improvements in the standards of living of most people. Rather than triggering a convergence across the three nations, NAFTA has accentuated the economic and regulatory asymmetries that had existed among the three countries. [TRUNCATED
Candidate Gene-Based Association Study of Antipsychotic-Induced Movement Disorders in Long-Stay Psychiatric Patients: A Prospective Study
OBJECTIVE: Four types of antipsychotic-induced movement disorders: tardive dyskinesia (TD), parkinsonism, akathisia and tardive dystonia, subtypes of TD (orofacial and limb truncal dyskinesia), subtypes of parkinsonism (rest tremor, rigidity, and bradykinesia), as well as a principal-factor of the movement disorders and their subtypes, were examined for association with variation in 10 candidate genes (PPP1R1B, BDNF, DRD3, DRD2, HTR2A, HTR2C, COMT, MnSOD, CYP1A2, and RGS2). METHODS: Naturalistic study of 168 white long-stay patients with chronic mental illness requiring long-term antipsychotic treatment, examined by the same rater at least two times over a 4-year period, with a mean follow-up time of 1.1 years, with validated scales for TD, parkinsonism, akathisia, and tardive dystonia. The authors genotyped 31 SNPs, associated with movement disorders or schizophrenia in previous studies. Genotype and allele frequency comparisons were performed with multiple regression methods for continuous movement disorders. RESULTS: VARIOUS SNPS REACHED NOMINAL SIGNIFICANCE: TD and orofacial dyskinesia with rs6265 and rs988748, limb truncal dyskinesia with rs6314, rest tremor with rs6275, rigidity with rs6265 and rs4680, bradykinesia with rs4795390, akathisia with rs4680, tardive dystonia with rs1799732, rs4880 and rs1152746. After controlling for multiple testing, no significant results remained. CONCLUSIONS: The findings suggest that selected SNPs are not associated with a susceptibility to movement disorders. However, as the sample size was small and previous studies show inconsistent results, definite conclusions cannot be made. Replication is needed in larger study samples, preferably in longitudinal studies which take the fluctuating course of movement disorders and gene-environment interactions into account
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