Introducing knowledge processing technology to CAD/CAM

A method of introducing knowledge processing technology which will develop advanced CAD/CAM systems for engineering design programs is discussed. To achieve this objective it is necessary to establish the concept of an object model and a methodology for building it in computers.Trying engineering design and knowledge processing together is not an easy task. The reasons are two-fold: first, knowledge processing technology is still making rapid progress and we do not understand it yet completely, and second, in order to introduce knowledge processing technology into CAD/CAM we need to analyze the design-and-manufacturing process in detail and to find the best method to combine these two technologies. The task is further complicated because it can be done by those who have enough knowledge of both technologies only, and also because it may result in reorganization of the traditional design-and-manufacturing process.This paper describes the current state of knowledge processing technology as well as its limitations in achieving intelligent functions, and analyzes the manner of combining these two technologies.     

Surface characterization of modified glass fibers by inverse gas chromatography

The dispersive component of the surface free energy _d ^s of glass fibers and their acid-base interaction can be evaluated by the measurement of specific retention volumes of several kinds of probe molecules by use of an inverse gas chromatography. The effect of the treatment of glass fibers with silane-coupling agents was also evaluated. The specific retention volumes of n-alkanes changed linearly with theirC number or vapor pressure. Those of polar molecules varied with their donor number (DN) or acceptor number (AN). The _s ^d values and electron-accepting or donating abilities depended upon the kind of functional groups contained in the coupling agents.     

Thermogravimetry on wood powder-filled polyurethane composites derived from lignin

Novel polyurethane (PU) composites whose matrix is derived from lignin, molasses polyol and filler from wood powder were successfully prepared. Two kinds of polyol were mixed 0/100 to 100/0 in seven steps, and filler content was varied from 50 to 100 mass % to polyol content. Decomposition behaviour of PU composites was investigated by thermogravimetry. Apparent density and mechanical properties of the above composites were also measured. Surface texture was observed by scanning electron microscopy. Thermal decomposition of PU composites was found to occur in two stages. The first decomposition observed at 570–580 K (DT _d1, peak temperature of derivative curve) is attributed to the matrix of composites. The second stage decomposition depending on filler content, observed in a temperature range from 590 to 630 K (DT _d2), is attributable to filler homogenously associated with PU matrix. Marked differences were not found, when the kinds of lignin and molasses polyol composition were varied. The above PU composites were found to be thermally stabilised by the introduction of filler.