ICT Diffusion and Economic Growth in New Zealand

Two different theoretical treatments of technology diffusion in an economy are examined. The traditional model based on the aggregate production function approach first introduced by Solow (1957) assumes technology is unstructured and arrives as a continuous exogenous flow. This model predicts that the diffusion of new technologies will be contemporaneously correlated with growth in economic performance indicators. An alternative view explicitly models technological structure in the form of complementarities. It also incorporates the observation that new general purpose technologies (GPTs) invariably emerge in a crude form lacking many of the complementarities that enable them to become productive. This view predicts that when new technologies emerge costly investment in developing complementary technologies must take place and thus there will be a lag between the new technology’s introduction and observed growth in economic performance indicators. These two views articulate two general empirically testable hypotheses that are captured in a number of specific tests. One such test measures diffusion of information and communication technologies (ICT) as an independent phenomenon and compares its times series pattern to that of the growth of total factor productivity (TFP) in New Zealand. New Zealand’s experience in consistent with other OECD economies where the diffusion of ICT has occurred at the same time as a TFP slowdown. Another test measures relative ICT-skilled labour demand. Findings support the non-traditional view’s prediction that ICT-skilled labour will increase with the diffusion of ICT technology in New Zealand.ICT, Productivity, Diffusion Technology

A Millimeter-Wave Achromatic Half Wave Plate

We have constructed an achromatic half wave plate (AHWP) suitable for the millimeter wavelength band. The AHWP was made from a stack of three sapphire a-cut birefringent plates with the optical axes of the middle plate rotated by 50.5 degrees with respect to the aligned axes of the other plates. The measured modulation efficiency of the AHWP at 110 GHz was $96 \pm 1.5$%. In contrast, the modulation efficiency of a single sapphire plate of the same thickness was $43 \pm 4$%. Both results are in close agreement with theoretical predictions. The modulation efficiency of the AHWP was constant as a function of incidence angles between 0 and 15 degrees. We discuss design parameters of an AHWP in the context of astrophysical broad band polarimetry at the millimeter wavelength band.Comment: In print - Applied Optics, 14 pages, 7 figure

Implications of different spatial (and temporal) resolutions for integrated assessment modelling on the regional to local scale – nesting, coupling, or model integration?

Integrated assessment modelling (IAM) in general is currently applied to a range of environmental problems addressing aspects of air pollution and climate change, water pollution and many more. While different branches have emerged from applications within different disciplines, they share a similar view of the core features of IAM, i.e. multi-disciplinary approaches, integration across environmental compartments, and the application of models with the aim to provide decision support for complex problems. Examples of IAMs on a regional scale are the RAINS/GAINS model suite (International Institute for Applied Systems Analysis, IIASA), with versions for Europe and Asia. On a national scale, several European countries are currently developing and applying IAMs for policy development, in some cases using special adaptations of the IIASA RAINS/GAINS model (e.g. Italy), or own models (UK, Germany). IAMs have been extensively used in the preparation of the Multi-Effect Protocol (United Nations Convention on Long-Range Transboundary Air Pollution, CLRTAP) and the European Clean Air For Europe (CAFE) strategy. In these applications, target setting included a mixture of health and ecosystem related indicators. State-of-the-art IAMs are typically operating on rigid spatial scales, and in most cases do not take into account the temporal patterns of emissions and effects in their assessment approaches. IAM results are typically provided on national or regional level (e.g. control measures, costs, benefits due to reduced environmental and health impacts) and for annual indicators (e.g. critical load exceedances or morbidity/mortality effects. However, scientific evidence is today capable of providing a better foundation to identify major aspects for uncertainties in these larger scale assessments, for instance investigating the distinct temporal patterns of air quality throughout the year and the detailed modelling and mapping of human exposure to air pollutants beyond statistical average exposures on total population level. This requires a more advanced and flexible design of IAMs to better model the temporal and spatial domains which are of relevance for the key issues to be assessed. First steps towards bridging the gap between regional and national, respectively national and local scale models for integrated assessments have taken the route to derive parameters for e.g. the urban differential in ambient air quality outside of the models regular domain and integrate these parametric values into the IAMs assessments. While this approach is moderately labour intensive, the major flaw is the integration of static values into an intrinsically dynamic model. In other words, if input datasets and external drivers (e.g. meteorology, atmospheric composition and chemistry) change, all other parameters have to be recalculated and re-integrated. This paper will discuss emerging trends for IAMs with a specific focus on spatial and temporal aspects and aims to elaborate on the policy context which is a key driver for the development of IAMs. The growing understanding of how complex interactions e.g. between/within the nitrogen and carbon cycles, where both management options and effects arise/occur on different spatial scales and with different time scales, both feeds into and requires the development of next generation IAMs, which are capable of tackling these problems

Feynman graph polynomials

The integrand of any multi-loop integral is characterised after Feynman parametrisation by two polynomials. In this review we summarise the properties of these polynomials. Topics covered in this article include among others: Spanning trees and spanning forests, the all-minors matrix-tree theorem, recursion relations due to contraction and deletion of edges, Dodgson's identity and matroids.Comment: 35 pages, references adde

Atomic-scale compensation phenomena at polar interfaces

The interfacial screening charge that arises to compensate electric fields of dielectric or ferroelectric thin films is now recognized as the most important factor in determining the capacitance or polarization of ultrathin ferroelectrics. Here we investigate using aberration-corrected electron microscopy and density functional theory how interfaces cope with the need to terminate ferroelectric polarization. In one case, we show evidence for ionic screening, which has been predicted by theory but never observed. For a ferroelectric film on an insulating substrate, we found that compensation can be mediated by interfacial charge generated, for example, by oxygen vacancies.Comment: 3 figure

The economics of phosphorus supplementation of beef cattle grazing northern Australian rangelands

Context: Phosphorus (P) deficiency occurs in beef cattle grazing many rangeland regions with low-P soils, including in northern Australia, and may severely reduce cattle productivity in terms of growth, reproductive efficiency and mortality. However, adoption of effective P supplementation by cattle producers in northern Australia is low. This is likely to be due to lack of information and understanding of the profitability of P supplementation where cattle are P-deficient. Aims: The profitability of P supplementation was evaluated for two dissimilar regions of northern Australia, namely (1) the Katherine region of the Northern Territory, and (2) the Fitzroy Natural Resource Management (NRM) region of central Queensland. Methods: Property-level, regionally relevant herd models were used to determine whole-of-business productivity and profitability over 30 years. The estimated costs and benefits of P supplementation were obtained from collation of experimental data and expert opinion of persons with extensive experience of the industry. The economic consequences of P supplementation at the property level were assessed by comparison of base production without P supplementation with the expected production of P-supplemented herds, and included the implementation phase and changes over time in herd structure. In the Katherine region, it was assumed that the entire cattle herd (breeders and growing cattle) grazed acutely P-deficient land types and the consequences of (1) no P supplementation, or P supplementation during (2) the dry season, or (3) both the wet and dry seasons (i.e. 3 scenarios) were evaluated. In the Fitzroy NRM region, it was assumed that only the breeders grazed P-deficient land types with three categories of P deficiency (marginal, deficient and acutely deficient), each with either (1) no P supplementation, or P supplementation during (2) the wet season, (3) the dry season, or (4) both the wet and dry seasons (i.e. 12 scenarios). Key results: In the Katherine region, year-round P supplementation of the entire cattle herd (7400 adult equivalents) grazing acutely P-deficient pasture resulted in a large increase in annual business profit (+AU$500 000). Supplementing with P (and N) only in the dry season increased annual business profit by +AU$200 000. In the Fitzroy NRM region, P supplementation during any season of the breeder herd grazing deficient or acutely P-deficient pastures increased profit by +AU$2400–AU$45 000/annum (total cattle herd 1500 adult equivalents). Importantly, P supplementation during the wet season-only resulted in the greatest increases in profit within each category of P deficiency, comprising +AU$5600, AU$6300 and AU$45 000 additional profit per annum for marginal, deficient and acutely P-deficient herds respectively. Conclusions: The large economic benefits of P supplementation for northern beef enterprises estimated in the present study substantiate the current industry recommendation that effective P supplementation is highly profitable when cattle are grazing P-deficient land types. Implications: The contradiction of large economic benefits of P supplementation and the generally low adoption rates by the cattle industry in northern Australia suggests a need for targeted research and extension to identify the specific constraints to adoption, including potential high initial capital costs

Real world CO2 and NOx emissions from 149 Euro 5 and 6 diesel, gasoline and hybrid passenger cars.

In this study CO2 and NOx emissions from 149 Euro 5 and 6 diesel, gasoline and hybrid passenger cars were compared using a Portable Emissions Measurement System (PEMS). The models sampled accounted for 56% of all passenger cars sold in Europe in 2016. We found gasoline vehicles had CO2 emissions 13-66% higher than diesel. During urban driving, the average CO2 emission factor was 210.5 (sd. 47) gkm-1 for gasoline and 170.2 (sd. 34) gkm-1 for diesel. Half the gasoline vehicles tested were Gasoline Direct Injection (GDI). Euro 6 GDI engines <1.4ℓ delivered ~17% CO2 reduction compared to Port Fuel Injection (PFI). Gasoline vehicles delivered an 86-96% reduction in NOx emissions compared to diesel cars. The average urban NOx emission from Euro 6 diesel vehicles 0.44 (sd. 0.44) gkm-1 was 11 times higher than for gasoline 0.04 (sd. 0.04) gkm-1. We also analysed two gasoline-electric hybrids which out-performed both gasoline and diesel for NOx and CO2. We conclude action is required to mitigate the public health risk created by excessive NOx emissions from modern diesel vehicles. Replacing diesel with gasoline would incur a substantial CO2 penalty, however greater uptake of hybrid vehicles would likely reduce both CO2 and NOx emissions. Discrimination of vehicles on the basis of Euro standard is arbitrary and incentives should promote vehicles with the lowest real-world emissions of both NOx and CO2

Relations between M\"obius and coboundary polynomial

It is known that, in general, the coboundary polynomial and the M\"obius polynomial of a matroid do not determine each other. Less is known about more specific cases. In this paper, we will try to answer if it is possible that the M\"obius polynomial of a matroid, together with the M\"obius polynomial of the dual matroid, define the coboundary polynomial of the matroid. In some cases, the answer is affirmative, and we will give two constructions to determine the coboundary polynomial in these cases.Comment: 12 page

The EBEX Experiment

EBEX is a balloon-borne polarimeter designed to measure the intensity and polarization of the cosmic microwave background radiation. The measurements would probe the inflationary epoch that took place shortly after the big bang and would significantly improve constraints on the values of several cosmological parameters. EBEX is unique in its broad frequency coverage and in its ability to provide critical information about the level of polarized Galactic foregrounds which will be necessary for all future CMB polarization experiments. EBEX consists of a 1.5 m Dragone-type telescope that provides a resolution of less than 8 arcminutes over four focal planes each of 4 degree diffraction limited field of view at frequencies up to 450 GHz. The experiment is designed to accommodate 330 transition edge bolometric detectors per focal plane, for a total of up to 1320 detectors. EBEX will operate with frequency bands centered at 150, 250, 350, and 450 GHz. Polarimetry is achieved with a rotating achromatic half-wave plate. EBEX is currently in the design and construction phase, and first light is scheduled for 2008.Comment: 13 pages, 10 figures. Figure 1 is changed from the one which appeared in the Proceedings of the SPI