Abstract: A method for monitoring time so that the use of protected content can be controlled includes receiving a trusted time value from a trusted authority external to a client device. When the client is no longer in communication with the trusted authority, the previously-received trusted time value is updated by use of the client's operating system counter so that a calculated trusted time value is derived for content license evaluation purposes.

Abstract: A license evaluation apparatus and method is disclosed which can specify the substance and the position of an error only with a simple description without the necessity to analyze the error in an ex post fact fashion. A data storage section stores licenses, and a content selection section selects a content. A license extraction section extracts the license from within the data storage section. A conditional expression decision section reads a conditional expression in use condition information of the license and an error code annexed in advance to the conditional expression and deciding whether or not the conditional expression is satisfied. If the conditional expression is not satisfied, an error code retaining section retains the error code. An application to which the error code is returned can specify the error without analyzing the error in an ex post fact fashion.

Abstract: Disclosed is a novel process of producing plate-shaped calcium carbonate particles. The process comprises the steps of adding aqueous calcium hydrogen carbonate solution with a temperature of less than 50.degree. C. into an aqueous medium bath held at a temperature of not less than 50.degree. C. to generate plate-shaped calcium carbonate particles in the bath, the temperature of the bath being kept not less than 50.degree. C. during the addition of the aqueous calcium hydrogen carbonate solution; and recovering the generated plate-shape calcium carbonate particles.

Abstract: Disclosed is a novel process of producing needle-shaped calcium carbonate particles. In the process of the present invention, aqueous calcium hydroxide solution is added to an aqueous medium bath with a temperature of not less than 60.degree. C. into which carbon dioxide gas or a carbon dioxide-containing gas is being blown to generate needle-shaped calcium carbonate particles. The temperature of the aqueous medium bath is kept not less than 60.degree. C. during the addition of the aqueous calcium hydroxide solution. Then the generated needle-shaped calcium carbonate particles are recovered.