4,508 research outputs found
Recent changes in U. S. family finances: results from the 1998 Survey of Consumer Finances
Using data from the Federal Reserve Board's two most recent Surveys of Consumer Finances, this article provides a detailed picture of changes in the financial condition of U.S. families between 1995 and 1998. The financial situation of families changed notably in the three-year period. While income continued a moderate upward trend, net worth grew strongly, and the increase in net worth was broadly shared by different demographic groups. A booming stock market accounts for a substantial part of the rise in net worth, but the data also suggest that improvements in financial circumstances extended to many families that did not own stocks. The indebtedness of families grew, but less rapidly than their assets. Nonetheless, compared with 1995, debt repayments in 1998 accounted for a larger share of the income of the typical family with debt, and the proportion of debtors who were late with their payments by sixty days or more in the year preceding the survey was also higher.Income ; Consumer behavior ; Saving and investment
Normalised Root Mean Square and Amplitude of Sidebands of Vibration Response as Tools for Gearbox Diagnosis
Quick assessment of the condition of gearboxes used in helicopters is a safety requirement. One of the most widely used helicopter on-board-mounted condition monitoring system these days is the Health and Usage Monitoring System. It has been specifically designed to monitor the condition of all safety-critical components operating in the helicopter through calculation of so-called condition indicators (CIs) - signal processing routines designed to output a single number that represents the condition of the monitored component. Among number of available parameters, there is a couple of CIs that over the years of testing have earned a reputation of being the most reliable measures of the gear tooth condition. At the same time, however, it has been observed that in some cases, those techniques do not properly indicate the deteriorating condition with the propagation of a gear tooth fault with the period of operation. Hence, three more robust methods have been suggested, which are discussed in this article
AN ANALYSIS OF THE USE OF GRADES AND HOUSEBRAND LABELS IN THE RETAIL BEEF MARKET
The congruence of beef consumersÂ’ purchases with their stated preferences regarding internal fat content are examined. The role of U.S. Department of Agriculture (USDA) grades and housebrand labeling of beef in providing information to consumers is studied in the theoretical framework of search theory. The empirical results indicate that the current system of USDA grades and housebrand labels is not disseminating information regarding internal fat content effectively to consumers. Suggestions are made for providing consumers with better information and education necessary to increase congruence of expressed preferences regarding internal fat content and actual beef purchases.Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,
The Increase in Frictional Resistance Caused by Various Types of Rivet Heads as Determined by Tests of Planing Surfaces
The increase in the frictional resistance of a surface caused by the presence of rivet heads was determined by towing four planing surfaces of the same dimensions. One surface was smooth and represented a surface without rivet heads or one with perfectly flush countersunk rivets. The other three surfaces were each fitted with the same number of full-size rivet heads but of a different type arranged in the same pattern on each surface. The surfaces were towed at speeds representative of the high water speeds encountered by seaplanes during take-off and the range of Reynolds Number covered by the test was from 4 x 10(exp 6) to 18 x 10(exp 6). The rivet heads investigated were oval countersunk, brazier, and round for rivets having shanks 5/32 inch in diameter. The oval countersunk heads were sunk below the surface by dimpling the plating around them. The results of the tests showed that, for the rivet heads investigated, the increase in the friction coefficient of the surface is directly proportional to the height of the rivet head. The order of merit in regard to low resistance is flush countersunk, oval countersunk (whether sunk below the surface or not), brazier, and round
Electronic heat current rectification in hybrid superconducting devices
In this work, we review and expand recent theoretical proposals for the
realization of electronic thermal diodes based on tunnel-junctions of normal
metal and superconducting thin films. Starting from the basic rectifying
properties of a single hybrid tunnel junction, we will show how the
rectification efficiency can be largely increased by combining multiple
junctions in an asymmetric chain of tunnel-coupled islands. We propose three
different designs, analyzing their performance and their potential advantages.
Besides being relevant from a fundamental physics point of view, this kind of
devices might find important technological application as fundamental building
blocks in solid-state thermal nanocircuits and in general-purpose cryogenic
electronic applications requiring energy management.Comment: 9 pages, 5 color figure
Fluidic temperature control system for liquid- cooled space suits
Fluidic temperature control system for liquid cooled space suit
- …