Abstract: Library management for libraries of user-defined routines in a database system. Libraries are stored in a long-term storage device and loaded into working memory in the database system when routines in the libraries are to be executed. An unload thread is defined to carry out the process of unloading libraries from the working memory when such libraries are inactive. The unload thread becomes active on a defined timing interval. The unload thread accesses a hash table and a most recently used list to determine which of the loaded libraries is inactive and which of the libraries ought to be unloaded. The hash table maintains information as to which libraries have been accessed in the most recent past defined timing interval. The size of the most recently used list can be defined such that all libraries associated with the list are retained in working memory.

Abstract: A database management system provides for the execution of invokable user-defined routines. Applications specify user-defined routines as being threadsafe or not threadsafe and specify the language of user-defined routines. Execution of routines will be carried out dependent on the threadsafe characteristic of the routines and on the language of the routines. Routines are assigned to processes based on their language to have any given process execute routines of the same language. Routines that are specified to be threadsafe are executed in threads in a potentially multi-threaded process. Each routine that is specified to be not threadsafe is executed in a fenced-mode processes in which no other routine is being executed.

Abstract: A process for producing a robust ball that is robustly attached to a robust tether for use in a batting practice apparatus uses a commercially available elastic shock cord (bungee cord) for the tether. An anchor is formed at one end of the tether by bending an end portion 180 degrees back upon itself where the end portion is affixed by a ring shaped clamp. The ball is composed of a high density urethane foam and is produced by a molding process. The anchor portion of the tether is inserted in the mold and an activated liquid urethane mixture is poured into the mold, where foam is formed as the reaction continues. The resulting article is capable of withstanding 5000 powerful hits with a baseball bat.

Abstract: Library management for libraries of user-defined routines in a database system. Libraries are stored in a long-term storage device and loaded into working memory in the database system when routines in the libraries are to be executed. An unload thread is defined to carry out the process of unloading libraries from the working memory when such libraries are inactive. The unload thread becomes active on a defined timing interval. The unload thread accesses a hash table and a most recently used list to determine which of the loaded libraries is inactive and which of the libraries ought to be unloaded. The hash table maintains information as to which libraries have been accessed in the most recent past defined timing interval. The size of the most recently used list can be defined such that all libraries associated with the list are retained in working memory.

Abstract: A database management system provides for the execution of invokable user-defined routines. Applications specify user-defined routines as being threadsafe or not threadsafe and specify the language of user-defined routines. Execution of routines will be carried out dependent on the threadsafe characteristic of the routines and on the language of the routines. Routines are assigned to processes based on their language to have any given process execute routines of the same language. Routines that are specified to be threadsafe are executed in threads in a potentially multi-threaded process. Each routine that is specified to be not threadsafe is executed in a fenced-mode processes in which no other routine is being executed.

Abstract: An esthetic preformed crown for children which uses layers of a custom crown material applied as a veneer over non-precious, semiprecious and precious casting metals fabricated for the casting of custom copings and as an alternative to porcelain, vitrioids, copolyester, epoxy, and acrylics. The veneer is comprised of high density polyethylene, which is thermoformed over a screened preformed stainless steel crown to obtain the desired appearance. The crown material is specifically comprised of pigmented high-density polyethylene because of its high elastic limit great flexural strength, ability to withstand great shearing force when mechanically bonded to a preformed crown. The crown of the present invention has natural appearance of a vital tooth. The high density polyethylene veneer in this esthetic preformed crown has a greater bond strength than any current state of the art veneer or other facing material currently used on children's esthetic stainless steel crowns.

Abstract: The present invention relates to the method and apparatus for forming a dental crown on a prepared tooth. A dental appliance is provided in which a resinous jacket is provided, and is capable of serving both as a crown and a crown form, the jacket having relatively thinner, straight, side walls. When used as a crown, the inner surface of the jacket is coated with a bonding agent, and the jacket is then filled with a composite restorative material, after which, the jacket is fitted over the prepared tooth to be restored, to give a resultant highly effective crown, either by leaving the jacket in place, or by removing it, in which case the composite restorative material serves as the crown, standing alone.