Abstract: Compositions for low heat cements developed especially for massive concrete works and which exhibit a compressive strength/heat of hydration ratio of at least 7.0 at the age of 13 weeks. One of two inventions provides a powder prepared by mixing CaO, SiO.sub.2, and Al.sub.2 O.sub.3 materials, melting the mixture, quenching the melt, and grinding the quenched matter, the powder being composed mainly of amorphous substances and chemically having a CaO/SiO.sub.2 (molar ratio) of 0.8-1.5 and an Al.sub.2 O.sub.3 content of no more than 10 wt. %. The other invention provides a mixed powder comprising no less than 70 wt. % of a powder and no more than 30 wt. % of an addition (portland cement or the like), the powder being the same as that of the first invention in both predominance of amorphous substances and CaO/SiO.sub.2 (molar ratio) excepting the Al.sub.2 O.sub.3 content which is less than 12 wt. % in the second invention.

Abstract: An apparatus for displaying an image on a screen of a CRT (Cathode Ray Tube) applicable to a vehicle is disclosed in which the visual angle controlling filter (liquid crystal panel) is disposed in a front space of the screen of the CRT. When the vehicle runs, a predetermined voltage is applied to the visual angle controlling filter so that the light from the screen to a driver's seat is interrupted. At this time, the application of the voltage to the visual angle controlling filter is detected and a color hue of the image appearing on the screen is controlled so that all viewers except the vehicle driver can view the image on the screen through the visual angle controlling filter with the same color hue as that viewed when the vehicle stops and no application of the voltage to the visual angle controlling filter.

Abstract: First and second tool control blocks respectively precede and follow a corner on a tool path. A pulse distribution computation based on NC command data in the second block is not executed at the instant that a pulse distribution computation based on NC command data in the first block ends. Rather, a pulse distribution computation based on the NC command data in the second block is performed starting at the instant that a feed speed based on the NC command data in the first block is reduced to a prescribed speed by being decelerated. As a result, the torch of a gas cutting machine or the like will cut the corner portion quickly with a high degree of accuracy and without cutting the corner to an overly rounded shape.