A methodology to model the information structure of an organization

The Integrated Computer Aided Manufacturing (ICAM) program of the U.S. Air Force identified a need to better communicate and analyze manufacturing for the people involved in improving productivity. To satisfy that need, the ICAM program developed the IDEF (ICAM Definition) method to address particular characteristics of manufacturing. This IDEF method is equally applicable in analyzing other types of organizations. IDEF comprises three modeling methodologies: function model methodology (IDEF₀), information model methodology (IDEF₁) and dynamics model methodology (IDEF₂). This paper reports on the Information model methodology only. This methodology is used to construct an information model that helps in understanding the structure of information needed to support the functions of an organization.     

Dynamic Mechanical Analysis of Amorphous-Phase Organization in Acrylic Polymers

Factors affecting polymer network organization were studied in highly crosslinked acrylics of the type used in dental adhesive resins. The variables tested were comonomer content and processing conditions. BisEMA (2,2,-bis[4-(2-methacryloyloxyethoxy)-phenyl]-propane) and BisEMA + TEGDMA (triethyleneglycol dimethacrylate) were cured with and without 25% comonomer. Comonomers had characteristics that are expected to influence intrachain organization in amorphous phases: TEGDMA, crosslinking; methyl methacrylate (MMA), monomer conversion; isobornyl methacrylate (IBM), low cure shrinkage; tetrahydrofurfuryl methacrylate (THFM), antiplasticization. Dynamic mechanical analysis temperature scans were run at 0.1 Hz 2h or 24h after ambient cure, or 24h postcure after heating at 75° or 125°C. After 24h, tan δ maxima occurred in ranges centering on approximately -30°, 75° and 150°C (T_g). Heating at 125°C nearly eliminated all peaks except T_g, reduced tan δ peaks and increased T_g by 0–14°. T_g increased in the order: TEGDMA>125°C>IBM>MMA>75°C>2h>24h>THFM. The ability to crosslink, and postcure heating at 125°C, were the more important factors found to increase intrachain organization in amine-promoted, unfilled BisEMA resins of the type used in dental sealants, luting cements and bulk-filling resin composite materials.