Asian and OECD international R&D spillovers

Previous studies have demonstrated an empirical relationship between accumulated R&D expenditures and total factor productivity (TFP), and have shown that the benefits of R&D can spill across countries through trade. This paper extends these analyses to a sample of 15 OECD countries and six Asian countries, Chinese Taipei, India, Indonesia, Korea, Singapore and Thailand. An empirical model is estimated which relates TFP to domestic and foreign R&D activity, TFP catch-up and business cycle variables. Model estimates show that TFP and domestic R&D capital are positively related, and that domestic R&D has a relatively large impact on TFP growth in the NICs and LICs. Country-specific international R&D spillover elasticities are of mixed sign, and no apparent pattern by country group is evident. While this result does not change the earlier qualitative conclusions, it suggests that estimates of sample average R&D spillover elasticities should be cautiously interpreted.R&D activity; Asian and OECD spillovers

Advanced communications policy and adoption in rural Western Australia

Recent moves toward contestable universal service markets for rural areas raises issues of measuring the net cost of service provision. Measurement of net cost requires estimates of latent demand for advanced communications. This paper seeks for the first time to provide quantitative estimates of the magnitude of latent income pools available to carriers in rural WA. Estimates of latent expenditure on broadband services in rural WA are obtained using a combination of stated-preference and survey data. These expenditures increase with computer ownership, community isolation and information need. Further, the statistical model supports the commonly held belief that more distant populations have stronger information demands and are willing to pay for services. This finding suggests that carrier aversion to providing services to rural regions may not be justified on commercial grounds.Advanced communications; broadband service; internet rural access; universal service obligations

Performance Analysis Of Strapdown Systems

ABSTRACT This paper provides an overview of assorted analysis techniques associated with strapdown inertial navigation systems. The process of strapdown system algorithm validation is discussed. Closed-form analytical simulator drivers are described that can be used to exercise/validate various strapdown algorithm groups. Analytical methods are presented for analyzing the accuracy of strapdown attitude, velocity and position integration algorithms (including position algorithm folding effects) as a function of algorithm repetition rate and system vibration inputs. Included is a description of a simplified analytical model that can be used to translate system vibrations into inertial sensor inputs as a function of sensor assembly mounting imbalances. Strapdown system static drift and rotation test procedures/equations are described for determining strapdown sensor calibration coefficients. The paper overviews Kalman filter design and covariance analysis techniques and describes a general procedure for validating aided strapdown system Kalman filter configurations. Finally, the paper discusses the general process of system integration testing to verify that system functional operations are performed properly and accurately by all hardware, software and interface elements. COORDINATE FRAMES As used in this paper, a coordinate frame is an analytical abstraction defined by three mutually perpendicular unit vectors. A coordinate frame can be visualized as a set of three perpendicular lines (axes) passing through a common point (origin) with the unit vectors emanating from the origin along the axes. In this paper, the physical position of each coordinate frame's origin is arbitrary. The principal coordinate frames utilized are the following: B Frame = "Body" coordinate frame parallel to strapdown inertial sensor axes. 1 N Frame = "Navigation" coordinate frame having Z axis parallel to the upward vertical at the local position location. A "wander azimuth" N Frame has the horizontal X, Y axes rotating relative to non-rotating inertial space at the local vertical component of earth's rate about the Z axis. A "free azimuth" N Frame would have zero inertial rotation rate of the X, Y axes around the Z axis. A "geographic" N Frame would have the X, Y axes rotated around Z to maintain the Y axis parallel to local true north. E Frame = "Earth" referenced coordinate frame with fixed angular geometry relative to the earth. I Frame = "Inertial" non-rotating coordinate frame. NOTATION V = Vector without specific coordinate frame designation. A vector is a parameter that has length and direction. The vectors used in the paper are classified as "free vectors", hence, have no preferred location in coordinate frames in which they are analytically described

Interannual variability of tropospheric composition:the influence of changes in emissions, meteorology and clouds

We have run a chemistry transport model (CTM) to systematically examine the drivers of interannual variability of tropospheric composition during 1996-2000. This period was characterised by anomalous meteorological conditions associated with the strong El Nino of 1997-1998 and intense wildfires, which produced a large amount of pollution. On a global scale, changing meteorology (winds, temperatures, humidity and clouds) is found to be the most important factor driving interannual variability of NO2 and ozone on the timescales considered. Changes in stratosphere-troposphere exchange, which are largely driven by meteorological variability, are found to play a particularly important role in driving ozone changes. The strong influence of emissions on NO2 and ozone interannual variability is largely confined to areas where intense biomass burning events occur. For CO, interannual variability is almost solely driven by emission changes, while for OH meteorology dominates, with the radiative influence of clouds being a very strong contributor. Through a simple attribution analysis for 1996-2000 we conclude that changing cloudiness drives 25% of the interannual variability of OH over Europe by affecting shortwave radiation. Over Indonesia this figure is as high as 71%. Changes in cloudiness contribute a small but non-negligible amount (up to 6%) to the interannual variability of ozone over Europe and Indonesia. This suggests that future assessments of trends in tropospheric oxidizing capacity should account for interannual variability in cloudiness, a factor neglected in many previous studies

Silicon isotopes reveal recycled altered oceanic crust in the mantle sources of ocean island basalts

EP thanks the Chateaubriand STEM fellowship program for funding. FM thanks the European Research Council under the European Community’s H2020 framework program/ERC grant agreement #637503 (Pristine) and the Agence Nationale de la Recherche for a chaire d’Excellence Sorbonne Paris Cité (IDEX13C445) and for the UnivEarthS Labex program (ANR-10-LABX-0023 and ANR-11-IDEX-0005-02). PS thanks the support of the Marie Curie FP7-IOF fellowship “Isovolc”.The study of silicon (Si) isotopes in Ocean Island Basalts (OIB) has the potential to discern between different models for the origins of geochemical heterogeneities in the mantle. Relatively large (∼several per mil per atomic mass unit) Si isotope fractionation occurs in low-temperature environments during biochemical and geochemical precipitation of dissolved Si, where the precipitate is preferentially enriched in the lighter isotopes relative to the dissolved Si. In contrast, only a limited range (∼tenths of a per mil) of Si isotope fractionation has been observed from high-temperature igneous processes. Therefore, Si isotopes may be useful as tracers for the presence of crustal material within OIB mantle source regions that experienced relatively low-temperature surface processes in a manner similar to other stable isotope systems, such as oxygen. Characterizing the isotopic composition of the mantle is also of central importance to the use of the Si isotope system as a basis for comparisons with other planetary bodies (e.g., Moon, Mars, asteroids). Here we present the first comprehensive suite of high-precision Si isotope data obtained by MC-ICP-MS for a diverse suite of OIB. Samples originate from ocean islands in the Pacific, Atlantic, and Indian Ocean basins and include representative end-members for the EM-1, EM-2, and HIMU mantle components. On average, δ30Si values for OIB (−0.32 ± 0.09‰, 2 sd) are in general agreement with previous estimates for the δ30Si value of Bulk Silicate Earth (−0.29 ± 0.07‰, 2 sd; Savage et al., 2014). Nonetheless, some small systematic variations are present; specifically, most HIMU-type (Mangaia; Cape Verde; La Palma, Canary Islands) and Iceland OIB are enriched in the lighter isotopes of Si (δ30Si values lower than MORB), consistent with recycled altered oceanic crust and lithospheric mantle in their mantle sources.PostprintPeer reviewe

Asian and OECD international R&D spillovers

Previous studies have demonstrated an empirical relationship between accumulated R&D expenditures and total factor productivity (TFP), and have shown that the benefits of R&D can spill across countries through trade. This paper extends these analyses to a sample of 15 OECD countries and six Asian countries, Chinese Taipei, India, Indonesia, Korea, Singapore and Thailand. An empirical model is estimated which relates TFP to domestic and foreign R&D activity, TFP catch-up and business cycle variables. Model estimates show that TFP and domestic R&D capital are positively related, and that domestic R&D has a relatively large impact on TFP growth in the NICs and LICs. Country-specific international R&D spillover elasticities are of mixed sign, and no apparent pattern by country group is evident. While this result does not change the earlier qualitative conclusions, it suggests that estimates of sample average R&D spillover elasticities should be cautiously interpreted

Asian and OECD international R&D spillovers

Previous studies have demonstrated an empirical relationship between accumulated R&D expenditures and total factor productivity (TFP), and have shown that the benefits of R&D can spill across countries through trade. This paper extends these analyses to a sample of 15 OECD countries and six Asian countries, Chinese Taipei, India, Indonesia, Korea, Singapore and Thailand. An empirical model is estimated which relates TFP to domestic and foreign R&D activity, TFP catch-up and business cycle variables. Model estimates show that TFP and domestic R&D capital are positively related, and that domestic R&D has a relatively large impact on TFP growth in the NICs and LICs. Country-specific international R&D spillover elasticities are of mixed sign, and no apparent pattern by country group is evident. While this result does not change the earlier qualitative conclusions, it suggests that estimates of sample average R&D spillover elasticities should be cautiously interpreted