The invention relates to a fast method of hierarchical searching for data satisfying at least one set of predetermined criteria C, in a directed acyclic graph which is stored in a relational database management system able to be interrogated by a query language, the criteria being determined on the nodes andor the links of the graph. In order to selectively transfer among all data the public data but to have confidential data remain excluded from the transfer or at least the presentation on the receiving computer, the presentation of the image data is discriminated dependent on at least one of the display values in the display value set. The objects may include a session dispatching object, a state machine object, a message parsing object, a protocol layering object, and a handler object. Phase-rotating sub-integer N frequency dividers are programmable to provide multi-modulus division with a wide range of arbitrary sub-integer division ratios. Another embodiment of the present invention is directed to a memory module comprising a substrate to which multiple memory chips are mounted and two or more voltage regulators mounted to, or fabricated within, the substrate.