2,743 research outputs found
HOW SUCCESSFUL ARE GOVERNMENT INTERVENTIONS IN FOOD MARKETS? INSIGHTS FROM THE PHILIPPINE RICE MARKET
We investigate the Philippine government's price stabilization policy for rice. Seemingly Unrelated Regressions are used to examine the effectiveness of the program at regional and national levels over a 21-year period (January 1983 to December 2003). Results of the regional analysis indicate some NFA-induced spatial and temporal differences in terms of producer prices. The NFA successfully increased producer prices in 5 of 13 regions through stock accumulation and paddy rice purchase at floor prices. NFA stock releases do not correlate strongly with retail prices at the national level, although results from the regional model indicate that NFA stock releases reduced retail prices in five regions, leading to perceptible spatial and temporal differences between regions. Although the NFA support price appears to have been moderately successful in increasing producer prices at a national level, on average, the support price led to an increase in consumer prices in ten regions and contributed little to price stabilization. Overall, therefore, our results indicate very limited success on the part of the NFA to achieve its major objectives at either regional or national level. We suggest the NFA should concentrate its resources in the poorest areas of the country, where it might exert greater and more useful influence in smaller and locally thin rice markets.Marketing,
The Value of Backyard Biodiversity in New Zealand
New Zealand's biodiversity consists of over 80,000 types of native plants, animals and fungi, a considerable number of which are indigenous and located on private property. To preserve and enhance native biodiversity and discourage activities that may deplete it, economic values can be calculated which can, in turn, guide the use of policy tools, such as incentives, that can be used. This can support behavioural changes by encouraging individual self-interest to coincide with social interest. In this project, we used the contingent valuation, choice modelling and well-being approaches to estimate native biodiversity values for Wellington residents. In this paper, we present a summary of our initial results.New Zealand, biodiversity, non-market valuation, well-being, native species, private landholders, Resource /Energy Economics and Policy,
Valuing Avoided Soil Erosion by Considering Private and Public Net Benefits
The population in New Zealand is expected to increase to over five million by the mid 2020’s from the current level of 4.3 million (Statistics New Zealand, 2009). An increasing demand for primary produce as a result may put pressure on marginal land to be farmed. Understanding the economic value of avoided erosion in New Zealand is therefore an important factor in policy making to optimise the soil related activities in the economy. Establishing a methodology for estimating the economic value of avoided soil erosion is the first step in assessing the problem. This study uses the future forest scenarios developed by Scion to identify potential afforestation areas and thereby compare the current erosion/sedimentation status under current land-use (non woody vegetation) with potential future afforestation. The study aims to quantify the incremental public and private net benefits from the change in scenario. The notion has come under different headings in the literature, such as on-site and off-site erosion effects or sediment and soil erosion effects, all of which recognize the importance of separation of effects to avoid double-counting. The separation into public and private benefits and costs in this case, while avoiding double-counting, will also help identify appropriate policy instruments to avoid soil erosion damage using the private and public net benefit framework (Pannell, 2008).Environmental Economics and Policy, Land Economics/Use,
Coordination-controlled electrodeposition of palladium/copper thin films onto a pyridine-terminated self-assembled monolayer
Support by the Chinese Scholarship Council and the University of St Andrews for a stipend (Z. Y.) are gratefully acknowledged. Electron microscopy was carried out at the Electron Microscopy Facility, School of Chemistry, University of St Andrews and we acknowledge recent funding for the Facility from the EPSRC (EP/T019298/1, EP/L017008/1) and the EPSRC Strategic Resources Grant (EP/R023751/1).A scheme for the electrodeposition of ultrathin bimetallic layers on top of a self-assembled monolayer (SAM) is investigated which combines the deposition of one metal (Pd) coordinated to a functionalized SAM (3-(4-pyridine-4-yl-phenyl)-propane-1-thiol, PyP3) on Au/mica with another metal (Cu) from the bulk electrolyte. The coordination-controlled electrodeposition (CCED) is a four-phase process comprising (i) Pd2+ coordination to the terminal pyridine units of the SAM, (ii) reduction of Pd and nanoparticle formation, (iii) formation of an intermixed shell of Pd and Cu, and (iv) deposition of bulk Cu. Chronoamperometry reveals a fast nucleation phase where Pd nanoparticles form within a few milliseconds and seed the Cu deposition. The Pd-Cu core-shell nature of deposited nanoparticles is confirmed by transmission electron microscopy (TEM). Harnessing the selective coordination of Pd2+ to PyP3, a one-pot procedure is further developed using electrolytes containing both Pd2+ and Cu2+ ions. Thus simplifying complexation and reduction, continuous Pd/Cu films are obtained in a multistep process as verified by scanning tunneling microscopy (STM). With a percolation threshold below 3 nm, CCED, as a SAM-controlled deposition strategy, offers an avenue for generation of ultrathin films.Publisher PDFPeer reviewe
Electronic structure of optimally doped pnictide BaKFeAs: a comprehensive ARPES investigation
We have conducted a comprehensive angle-resolved photoemission study on the
normal state electronic structure of the Fe-based superconductor
BaKFeAs. We have identified four dispersive bands which
cross the Fermi level and form two hole-like Fermi surfaces around and
two electron-like Fermi surfaces around M. There are two nearly nested Fermi
surface pockets connected by an antiferromagnetic (, ) wavevector.
The observed Fermi surfaces show small dispersion and a total volume
consistent with Luttinger theorem. Compared to band structure calculations, the
overall bandwidth is reduced by a factor of 2. However, many low energy
dispersions display stronger mass renormalization by a factor of 4,
indicating possible orbital (energy) dependent correlation effects. Using an
effective tight banding model, we fitted the band structure and the Fermi
surfaces to obtain band parameters reliable for theoretical modeling and
calculations of the important physical quantities, such as the specific heat
coefficient.Comment: 13 pages, 4 figure
Non-locality and Communication Complexity
Quantum information processing is the emerging field that defines and
realizes computing devices that make use of quantum mechanical principles, like
the superposition principle, entanglement, and interference. In this review we
study the information counterpart of computing. The abstract form of the
distributed computing setting is called communication complexity. It studies
the amount of information, in terms of bits or in our case qubits, that two
spatially separated computing devices need to exchange in order to perform some
computational task. Surprisingly, quantum mechanics can be used to obtain
dramatic advantages for such tasks.
We review the area of quantum communication complexity, and show how it
connects the foundational physics questions regarding non-locality with those
of communication complexity studied in theoretical computer science. The first
examples exhibiting the advantage of the use of qubits in distributed
information-processing tasks were based on non-locality tests. However, by now
the field has produced strong and interesting quantum protocols and algorithms
of its own that demonstrate that entanglement, although it cannot be used to
replace communication, can be used to reduce the communication exponentially.
In turn, these new advances yield a new outlook on the foundations of physics,
and could even yield new proposals for experiments that test the foundations of
physics.Comment: Survey paper, 63 pages LaTeX. A reformatted version will appear in
Reviews of Modern Physic
Current models of the observable consequences of cosmic reionization and their detectability
A number of large current experiments aim to detect the signatures of the cosmic reionization at redshifts z > 6. Their success depends crucially on understanding the character of the reionization process and its observable consequences and designing the best strategies to use. We use large-scale simulations of cosmic reionization to evaluate the reionization signatures at redshifted 21-cm and small-scale cosmic microwave background (CMB) anisotropies in the best current model for the background universe, with fundamental cosmological parameters given by Wilkinson Microwave Anisotropy Probe three-year results. We find that the optimal frequency range for observing the `global step of the 21-cm emission is 120150 MHz, while statistical studies should aim at 140160 MHz, observable by GMRT. Some strongly non-Gaussian brightness features should be detectable at frequencies up to ~190 MHz. In terms of sensitivity-signal trade-off relatively low resolutions, corresponding to beams of at least a few arcminutes, are preferable. The CMB anisotropy signal from the kinetic SunyaevZel'dovich effect from reionized patches peaks at tens of K at arcminute scales and has an rms of ~1 K, and should be observable by the Atacama Cosmology Telescope and the South Pole Telescope. We discuss the various observational issues and the uncertainties involved, mostly related to the poorly known reionization parameters and, to a lesser extend, to the uncertainties in the background cosmology
Socio-economic vision graph generation and handover in distributed smart camera networks
In this article we present an approach to object tracking handover in a network of smart cameras, based on self-interested autonomous agents, which exchange responsibility for tracking objects in a market mechanism, in order to maximise their own utility. A novel ant-colony inspired mechanism is used to learn the vision graph, that is, the camera neighbourhood relations, during runtime, which may then be used to optimise communication between cameras. The key benefits of our completely decentralised approach are on the one hand generating the vision graph online, enabling efficient deployment in unknown scenarios and camera network topologies, and on the other hand relying only on local information, increasing the robustness of the system. Since our market-based approach does not rely on a priori topology information, the need for any multicamera calibration can be avoided. We have evaluated our approach both in a simulation study and in network of real distributed smart cameras
A Dynamic Knowledge Management Framework for the High Value Manufacturing Industry
Dynamic Knowledge Management (KM) is a combination of cultural and technological factors, including the cultural factors of people and their motivations, technological factors of content and infrastructure and, where these both come together, interface factors. In this paper a Dynamic KM framework is described in the context of employees being motivated to create profit for their company through product development in high value manufacturing. It is reported how the framework was discussed during a meeting of the collaborating company’s (BAE Systems) project stakeholders. Participants agreed the framework would have most benefit at the start of the product lifecycle before key decisions were made. The framework has been designed to support organisational learning and to reward employees that improve the position of the company in the market place
VLASS tidal disruption events with optical flares I: the sample and a comparison to optically-selected TDEs
In this work, we use the Jansky VLA Sky Survey (VLASS) to compile the first
sample of six radio-selected tidal disruption events (TDEs) with transient
optical counterparts. While we still lack the statistics to do detailed
population studies of radio-selected TDEs, we use these events to suggest
trends in host galaxy and optical light curve properties that may correlate
with the presence of radio emission, and hence can inform optically-selected
TDE radio follow-up campaigns. We find that radio-selected TDEs tend to have
faint and cool optical flares, as well as host galaxies with low SMBH masses.
Our radio-selected TDEs also tend to have more energetic, larger radio emitting
regions than radio-detected, optically-selected TDEs. We consider possible
explanations for these trends, including by invoking super-Eddington accretion
and enhanced circumnuclear media. Finally, we constrain the radio-emitting TDE
rate to be Gpc yr.Comment: 26 pages, 5 tables, 11 figures, submitted to Ap
- …