The Asymmetric Effects of Changes in Price and Income on Energy and Oil Demand

This paper estimates the effects on energy and oil demand of changes in income and oil prices, for 96 of the world's largest countries, in per-capita terms. We examine three important issues: the asymmetric effects on demand of increases and decreases in oil prices; the asymmetric effects on demand of increases and decreases in income; and the different speeds of demand adjustment to changes in price and in income. Its main conclusions are the following: (1) OECD demand responds much more to increases in oil prices than to decreases; ignoring this asymmetric price response will bias downward the estimated income elasticity; (2) demand's response to income decreases in many non-OECD countries is not necessarily symmetric to its response to income increases; ignoring this asymmetric income response will bias the estimated income elasticity; (3) the speed of demand adjustment is faster to changes in income than to changes in price; ignoring this difference will bias upward the estimated response to income changes. Using correctly specified equations for energy and oil demand, the long-run elasticity for increases in income is about 0.55 for OECD energy and oil, and 1.0 or higher for Non-OECD Oil Exporters, Income Growers and perhaps all Non-OECD countries. These income elasticity estimates are significantly higher than current estimates used by the US Department of Energy. Our estimates for the OECD countries are also higher than those estimated recently by Schmalensee-Stoker-Judson (1998) and Holtz-Eakin and Selden (1995), who ignore the asymmetric effects of prices on demand. Higher income elasticities, of course, will increase projections of energy and oil demand, and of carbon dioxide emissions.ENERGY DEMAND; OIL DEMAND; ASYMMETRY; IRREVERSIBILITY; INCOME ELASTICITY

What do faculty and students really think about e-books?

Purpose - The purpose of this article is to report on a large-scale survey that was carried Out to assess academic users' awareness, perceptions and existing levels of use of e-books. The survey also seeks to find out about the purposes to which electronic books were put, and to obtain an understanding of the most effective library marketing and communication channels.Design/methodology/approach - An e-mail invitation to participate in the survey was distributed to all UCL staff and students (approximately 27,000) in November 2006, and 1,818 completions were received, an effective response rate of at least 6.7 per cent. Statistical analyses were carried out on the data using Software Package for Social Sciences (SPSS).Findings - The survey findings point to various ways in which user uptake and acceptance of e-books may be encouraged. Book discovery behaviour, a key issue for publishers and librarians in both print and electronic environments, emerges as a critical focus for service delivery and enhancement.Originality/value - The survey is part of an action research project, CIBER's SuperBook, that will further investigate the issues raised in this initial benchmarking survey using deep log analysis and qualitative methods. The paper partly fills the gap in the literature on e-books which has mainly focused on usage and not the users

An Appraisal of FOPIM Fast-converging Perturbation Method

Appraisal of first order perturbation iteration fast converging metho

Diamond chemical vapor deposition on optical fibers for fluorescence waveguiding

A technique has been developed for depositing diamond crystals on the endfaces of optical fibers and capturing the fluorescence generated by optically active defects in the diamond into the fiber. This letter details the diamond growth on optical fibers and transmission of fluorescence through the fiber from the nitrogen-vacancy (N-V) color center in diamond. Control of the concentration of defects incorporated during the chemical vapor deposition (CVD) growth process is also demonstrated. These are the first critical steps in developing a fiber coupled single photon source based on optically active defect centers in diamond.Comment: 10 pages, 3 figure

Are there spurious temperature trends in the United States Climate Division database

The United States (U.S.) Climate Division data set is commonly used in applied climatic studies in the United States. The divisional averages are calculated by including all available stations within a division at any given time. The averages are therefore vulnerable to shifts in average station location or elevation over time, which may introduce spurious trends within these data. This paper examines temperature trends within the 15 climate divisions of New England, comparing the NCDC\u27s U.S. Divisional Data to the U.S. Historical Climate Network (USHCN) data. Correlation and multiple regression revealed that shifts in latitude, longitude, and elevation have affected the quality of the NCDC divisional data with respect to the USHCN. As a result, there may be issues with regard to their use in decadal- to century-scale climate change studies

The health and wellbeing of adults working in early childhood education

This article reports the results of a survey of 168 New Zealand early childhood workers and describes their health status, behaviours and concerns. The respondents included 73 childcare teachers, 58 kindergarten teachers and 37 home-based educators. Although 92 per cent of respondents reported that they had good or excellent health, statistically significant differences were found between the groups for days absent because of illness, accidental injuries, job-related stress and ergonomic aspects of their work. All groups reported an increase in various physical symptoms since working with children, in particular backaches, muscle strain and fatigue. One-quarter of respondents experienced an illness related to their work with children during the past year, most commonly respiratory and gastrointestinal illnesses. The study alerts early childhood education employers to the importance of managing health issues such as workload and stress, occupational injuries, the provision of an ergonomically healthy work environment and adequate conditions of employment

Elastic properties of hydrogenated graphene

There exist three conformers of hydrogenated graphene, referred to as chair-, boat-, or washboard-graphane. These systems have a perfect two-dimensional periodicity mapped onto the graphene scaffold, but they are characterized by a $sp^3$ orbital hybridization, have different crystal symmetry, and otherwise behave upon loading. By first principles calculations we determine their structural and phonon properties, as well as we establish their relative stability. Through continuum elasticity we define a simulation protocol addressed to measure by a computer experiment their linear and nonlinear elastic moduli and we actually compute them by first principles. We argue that all graphane conformers respond to any arbitrarily-oriented extention with a much smaller lateral contraction than the one calculated for graphene. Furthermore, we provide evidence that boat-graphane has a small and negative Poisson ratio along the armchair and zigzag principal directions of the carbon honeycomb lattice (axially auxetic elastic behavior). Moreover, we show that chair-graphane admits both softening and hardening hyperelasticity, depending on the direction of applied load.Comment: submitted on Phys.Rev.

A neutral atom storage ring and intense cold atom source

Presented in this thesis is a proposed design for a continuously loaded permanent magnet meter scale storage ring for confining neutral atoms and molecules. Confinement is generated by neodymium magnets arranged to produce hexapole fields. The ring is in the shape of a “racetrack” with two bending sections of 1 meter radius and is composed entirely of linear segments of magnets. A permanent magnet injection system continuously guides particles from an existing source into the ring using an optical pumping scheme. The dynamics of the design are well explained by charged particle accelerator theory extended to neutral particles. The proposed design is over an order of magnitude larger than previous neutral atom storage rings and provides over 2 orders of magnitude greater trapping depth. An extensive simulation was developed to characterize and optimize the ring and injector system. The design is optimized for our existing source of ⁷Li atoms, although theory and simulation indicate it will work well with other paramagnetic species. With our source it is expected to build up a circulating flux of around 5 × 10¹⁴ atoms/s and an atom number of about 2 × 10¹³. It has previously been suggested that such a design is unstable, but in this work it is shown that an essential stability criteria was neglected. Also presented is the improvement and characterization of an intense, continuous cold atom beam to be used to load the storage ring. The beam is generated via post nozzle seeding of a supersonic cryogenic ⁴He jet with hot ⁷Li atoms. The atomic beam is brought to a focus 176 cm from the nozzle by a 10 cm bore diameter permanent magnet hexapole lens. At the focus the beam is measured to have a flux of 2.3(4) × 10¹² atoms/s, brightness of 1.8(6) × 10¹⁹ m⁻²s⁻¹sr⁻¹, forward velocity of 210(2) ms⁻¹, and longitudinal temperature of 7(3) mK. An improved vacuum design should yield around 10 times higher flux.Physic

A highly efficient two level diamond based single photon source

An unexplored diamond defect centre which is found to emit stable single photons at a measured rate of 1.6 MHz at room temperature is reported. The novel centre, identified in chemical vapour deposition grown diamond crystals, exhibits a sharp zero phonon line at 734 nm with a full width at half maximum of ~ 4 nm. The photon statistics confirm the center is a single emitter and provides direct evidence of the first true two-level single quantum system in diamond.Comment: 3 pages, 4 figure