Abstract: A scooter, for a handicapped person, has a platform. A front wheel is steerably mounted at a front of the platform. A rear drive wheel is mounted at a back of the platform. A motor is connected to drive the drive wheel. There is a power source for the motor. A pair of protective skirts are mounted to the sides of the platform. A pair of casters are mounted below the platform, at the lateral edges of the platform. The casters are within the protective skirts. The casters are protected by the protective skirts.

Abstract: A system for conducting performance analysis for executing tasks. The analysis involves generating a variety of trace information related to performance measures, including parallelism-related information, during execution of the task. In order to generate the trace information, target source code of interest is compiled in such a manner that executing the resulting executable code will generate execution trace information composed of a series of events. Each event stores trace information related to a variety of performance measures for the one or more processors and protection domains used. After the execution trace information has been generated, the system can use that trace information and a trace information description file to produce useful performance measure information. The trace information description file contains information that describes the types of execution events as well as the structure of the stored information.

Abstract: Various techniques for manipulating data using access states of memory, access control fields of pointers and operations, and exception raising and exception trapping in a multithreaded computer system. In particular, the techniques include synchronization support for a thread blocked in a word, demand evaluation of values, parallel access of multiple threads to a list, synchronized and unsynchronized access to a data buffer, use of forwarding to avoid checking for an end of a buffer, use of sentinel word to detect access past a data structure, concurrent access to a word of memory using different synchronization access modes, and use of trapping to detect access to restricted memory.