The Freshness of Web search engines’ databases

This study measures the frequency in which search engines update their indices. Therefore, 38 websites that are updated on a daily basis were analysed within a time-span of six weeks. The analysed search engines were Google, Yahoo and MSN. We find that Google performs best overall with the most pages updated on a daily basis, but only MSN is able to update all pages within a time-span of less than 20 days. Both other engines have outliers that are quite older. In terms of indexing patterns, we find different approaches at the different engines: While MSN shows clear update patterns, Google shows some outliers and the update process of the Yahoo index seems to be quite chaotic. Implications are that the quality of different search engine indices varies and not only one engine should be used when searching for current content

Interview with Henry Cord Meyer

Professor Emeritus of HistoryFounding Chair of Department of History, 1965Digitized 2013 by Avant Productions, Inc

Size and shape of clay grains as affected by various methods of grinding

It is a common belief among those persons manufacturing dry pressed brick that the shape of grain of the clay used for this purpose would materially affect the physical properties of the resultant product. Some believe that clays, dry pan-ground, give a better product than clays disintegrated mechanically or passed through rolls. In some recent dry press investigations it was found that some milling methods gave an advantage over other methods, in the matter of pressure transmission. Due to this, a possible cause for the advantage was attributed to the shape of the grains resulting from the various methods of grinding --Introduction, page 1

Paradoxes in Evaluating Mental Health Programmes

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67041/2/10.1177_002076405900500207.pd

E-Theory for C*-algebras over topological spaces

We define E-theory for separable C*-algebras over second countable topological spaces and establish its basic properties. This includes an approximation theorem that relates the E-theory over a general space to the E-theories over finite approximations to this space. We obtain effective criteria for determining the invertibility of E-theory elements over possibly infinite-dimensional spaces. Furthermore, we prove a Universal Multicoefficient Theorem for C*-algebras over totally disconnected metrisable compact spaces.Comment: 33 page

Investigation of Three Low-temperature-ratio Combustor Configurations in a 48-inch-diameter Ram-jet Engine

A preliminary evaluation was made of three types of combustor configurations in a 48-inch-diameter ram-jet engine to determine the one with the greatest promise of ultimately achieving efficient and stable combustion at low fuel-air rations and low combustor-inlet pressure. The combustor configurations evaluated include (1) a can-piloted configuration using a gutter-type flame holder with can-type pilot burners for stability, (2) an annular-piloted configuration using a gutter-type flame holder with an annular pilot burner to provide stability and to serve as a flow divider for confined fuel-air mixing, and (3) a can-type configuration using a flow divider for confined fuel-air mixing. No modifications were made to optimize the performance of any configuration. On the basis of this preliminary evaluation at an inlet-air temperature of about 990 degrees R, the annular-piloted combustor configuration appeared to have the greatest promise of permitting combustion efficiencies in excess of 0.90 at low fuel-air ratio with combustor-inlet pressures as low as 700 pounds per square foot absolute