Falling Gasoline Prices Lead to Lowest Inflation Since 2008

Overall price change was modest in 2014, with the U.S. All Items Consumer Price Index posting its smallest increase since 2008. This was primarily the result of gasoline prices, which fell sharply over the latter part of the year. However, shelter and food price indexes accelerated in 2014. In this Beyond the Numbers article, we will look at price trends for major CPI components in 2014

The influence of out-of-plane stress on a plane strain problem in rock mechanics

This paper analyses the stresses and displacements in a uniformly prestressed Mohr-Coulomb continuum, caused by the excavation of an infinitely long cylindrical cavity. It is shown that the solution to this axisymmetric problem passes through three stages as the pressure at the cavity wall is progressively reduced. In the first two stages it is possible to determine the stresses and displacements in the rθ-plane without consideration of the out-of plane stress . In the third stage it is shown that an inner plastic zone develops in whichzσzσ=σθ, so that the stress states lie on a singularity of the plastic yield surface. Using the correct flow rule for this situation, an analytic solution for the radial displacements is obtained. Numerical examples are given to demonstrate that a proper consideration of this third stage can have a significant effect on the cavity wall displacements

Fluctuating surface pressure measurements on USB wing using two types of transducers

Measurements of the fluctuating pressures on the wing surface of an upper-surface-blown powered-lift model and a JT15 engine were obtained using two types of pressure transducers. The pressures were measured using overall-fluctuating pressures and power spectral density analyses for various thrust settings and two jet impingement angles. Comparison of the data from the two transducers indicate that similar results are obtained in the lower frequency ranges for both transducers. The data also indicate that for this configuration, the highest pressure levels occur at frequencies below 2000 Hz

Measures of Gasoline Price Change

[Excerpt] No prices are more visible to the public than gasoline prices. Even for people who don’t have to fill up a tank on a regular basis, gasoline prices are likely to be in their view, posted every day. In addition, no prices have more of an impact on short-run movements in the Consumer Price Index (CPI). Gasoline prices are so much more volatile than other CPI components that, even though gasoline makes up less than 6 percent of the CPI, it is often the main source of monthly price movements in the all items index. Moreover, because they are so visible and gasoline is purchased so frequently, gasoline prices have a major impact on the perception of prices. Constantly seeing prices at the pump creep ever higher will often create a perception of broader inflation—and, of course, higher gasoline prices are likely to eventually have an impact on other prices as transportation costs increase. So, it is particularly important that gasoline price changes be measured accurately and reliably. Fortunately, gasoline is one of the few consumer goods for which there are many sources of price data. In fact, the ease of price collection makes it feasible for other government agencies and even private sources to create reliable measures. On the government side, the Energy Information Administration (EIA) publishes extensive gasoline price data. Among private sources are the American Automobile Association, the Oil Price Information Service, and the Lundberg Survey. Furthermore, gasoline is one of the few nonfood items for which the Bureau of Labor Statistics (BLS) publishes an average price series as well as an index; the fact that gasoline is a relatively homogenous product makes meaningful average price data possible. This article examines three measures of gasoline prices: the BLS Consumer Price Index for All Urban Consumers (CPI-U) U.S. city average for all types of gasoline, the BLS CPI average price series for all types of gasoline, and the EIA Weekly Retail Gasoline and Diesel Prices for all grades of gasoline. The purpose of the article is to identify how these measures have behaved over the 10-year period from December 2002 to December 2012

The 3D version of the finite element program FESTER

In this report, a detailed description of the 3-D version finite element pro-gram FESTER is given. This includes: 1. A brief introduction to the package FESTER; 2. Preparing an input data file for the 3D version of FESTER; 3. Principal stress and stress invariant analyses; 4. 2D joint element (surface contact) characterisation and its mathematical formulation; 5. Formulations of the 3D stress-strain analyses for both isotropic and anisotropic materials, plane of weakness and cracking criteria; 6. 3D brick elements, infinity elements and their corresponding shape and mapping functions; 7. Large-displacement formulations; 8. Modifications to the subroutines INVAR, JNTB, TMAT, MOD2 etc; 9. Numerical examples; and 10. Conclusions

Regularity of Bound States

We study regularity of bound states pertaining to embedded eigenvalues of a self-adjoint operator $H$, with respect to an auxiliary operator $A$ that is conjugate to $H$ in the sense of Mourre. We work within the framework of singular Mourre theory which enables us to deal with confined massless Pauli-Fierz models, our primary example, and many-body AC-Stark Hamiltonians. In the simpler context of regular Mourre theory our results boils down to an improvement of results obtained recently in \cite{CGH}.Comment: 70 page

Consumer Price Index Data Quality: How Accurate is the U.S. CPI?

The Consumer Price Index (CPI) is an estimate of the average change in prices over time paid by urban consumers for a market basket of consumer goods and n the United States. The CPI is used extensively in many different ways, including three major uses: to adjust historical data, to escalate federal payments and tax brackets, and to adjust rents and wages. It directly affects the lives of Americans, so it must be as accurate as possible. But how accurate is it? If, for example, the CPI measures annual inflation as 2.3 percent, how confident can we be in that estimate? This issue of BEYOND THE NUMBERS looks at some different ways the U.S. Bureau of Labor Statistics (BLS) has responded to questions about the accuracy and precision of the CPI. The first section examines the sampling error of the CPI, and the second section discusses possible sources of bias in the index

Generalized Wannier Functions

We consider single particle Schrodinger operators with a gap in the en ergy spectrum. We construct a complete, orthonormal basis function set for the inv ariant space corresponding to the spectrum below the spectral gap, which are exponentially localized a round a set of closed surfaces of monotonically increasing sizes. Estimates on the exponential dec ay rate and a discussion of the geometry of these surfaces is included