167 research outputs found
Crowdsourcing complex workflows under budget constraints
We consider the problem of task allocation in crowdsourcing systems with multiple complex workflows, each of which consists of a set of interdependent micro-tasks. We propose Budgeteer, an algorithm to solve this problem under a budget constraint. In particular, our algorithm first calculates an efficient way to allocate budget to each workflow. It then determines the number of inter-dependent micro-tasks and the price to pay for each task within each workflow, given the corresponding budget constraints. We empirically evaluate it on a well-known crowdsourcing-based text correction workflow using Amazon Mechanical Turk, and show that Budgeteer can achieve similar levels of accuracy to current benchmarks, but is on average 45% cheaper
Theoretical predictions of melting behaviors of hcp iron up to 4000 GPa
The high-pressure melting diagram of iron is a vital ingredient for the
geodynamic modeling of planetary interiors. Nonetheless, available data for
molten iron show an alarming discrepancy. Herein, we propose an efficient
one-phase approach to capture the solid-liquid transition of iron under extreme
conditions. Our basic idea is to extend the statistical moment method to
determine the density of iron in the TPa region. On that basis, we adapt the
work-heat equivalence principle to appropriately link equation-of-state
parameters with melting properties. This strategy allows explaining
cutting-edge experimental and ab initio results without massive computational
workloads. Our theoretical calculations would be helpful to constrain the
chemical composition, internal dynamics, and thermal evolution of the Earth and
super-Earths
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A Schrödinger Equation for Evolutionary Dynamics
We establish an analogy between the FokkerâPlanck equation describing evolutionary landscape dynamics and the Schrödinger equation which characterizes quantum mechanical particles, showing that a population with multiple genetic traits evolves analogously to a wavefunction under a multi-dimensional energy potential in imaginary time. Furthermore, we discover within this analogy that the stationary population distribution on the landscape corresponds exactly to the ground-state wavefunction. This mathematical equivalence grants entry to a wide range of analytical tools developed by the quantum mechanics community, such as the RayleighâRitz variational method and the RayleighâSchrödinger perturbation theory, allowing us not only the conduct of reasonable quantitative assessments but also exploration of fundamental biological inquiries. We demonstrate the effectiveness of these tools by estimating the population success on landscapes where precise answers are elusive, and unveiling the ecological consequences of stress-induced mutagenesisâa prevalent evolutionary mechanism in pathogenic and neoplastic systems. We show that, even in an unchanging environment, a sharp mutational burst resulting from stress can always be advantageous, while a gradual increase only enhances population size when the number of relevant evolving traits is limited. Our interdisciplinary approach offers novel insights, opening up new avenues for deeper understanding and predictive capability regarding the complex dynamics of evolving populations
A Schr\"odinger Equation for Evolutionary Dynamics
We establish an analogy between the Fokker-Planck equation describing
evolutionary landscape dynamics and the Schr\"{o}dinger equation which
characterizes quantum mechanical particles, showing how a population with
multiple genetic traits evolves analogously to a wavefunction under a
multi-dimensional energy potential in imaginary time. Furthermore, we discover
within this analogy that the stationary population distribution on the
landscape corresponds exactly to the ground-state wavefunction. This
mathematical equivalence grants entry to a wide range of analytical tools
developed by the quantum mechanics community, such as the Rayleigh-Ritz
variational method and the Rayleigh-Schr\"{o}dinger perturbation theory,
allowing us to not only make reasonable quantitative assessments but also
explore fundamental biological inquiries. We demonstrate the effectiveness of
these tools by estimating the population success on landscapes where precise
answers are elusive, and unveiling the ecological consequences of
stress-induced mutagenesis -- a prevalent evolutionary mechanism in pathogenic
and neoplastic systems. We show that, even in a unchanging environment, a sharp
mutational burst resulting from stress can always be advantageous, while a
gradual increase only enhances population size when the number of relevant
evolving traits is limited. Our interdisciplinary approach offers novel
insights, opening up new avenues for deeper understanding and predictive
capability regarding the complex dynamics of evolving populations
The Current State of Climate Change Perceptions and Policies in Vietnam: 2014 Report
This report was constructed to assess the current perceptions and policies regarding climate change in Vietnam. The report comprises a country report, outlining current policies relating to climate change, stakeholder mapping regarding climate change locally and nationally, and results from two stakeholder perception surveys conducted locally and nationally in Vietnam. A total of 50 stakeholders were interviewed, 25 locally and 25 nationally. The stakeholders in the survey represented government offices, universities, research institutions, NGOs, and farmersâ groups. Concerns about climate change impacts included drought, flooding, rainfall variation, and salinity intrusion. These concerns, as well as the methods in which stakeholders would like to receive climate information, varied between local and national stakeholders as well as by the type of institution that the stakeholder represented. This emphasizes a need for location- and user-specific responses to climate change
Gender Differences in Climate Change Perception and Adaptation Strategies: The Case of Three Provinces in Vietnamâs Mekong River Delta
The Policy Information and Response Platform on Climate Change and Rice in ASEAN and its
Member Countries Project (PIRCCA) is one of the trial projects funded under Flagship 4.
PIRCCA has an overarching goal to enable policymakers in ASEAN countries to make informed
decisions on (1) food security policies focusing on the supply and availability of rice, (2) climate
change adaptation policies, and (3) gender action plans
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