The present invention relates to a detection system for improving accuracy of hematocrit measurement and an operation control method. The method may also include forwarding a second enqueued read request to the system memory before receiving a response to a first forwarded enqueued read request. The present invention provides for the isolation, characterization and use of an entirely novel class of plant genes, generally designated ROB5. The virtual machine assigns speculative types to certain variables in the particular code segment by: assigning speculative types of first variables to respective observed types recorded in the type profiling data; calculating speculative types of second variables, based on propagating the speculative types of the first variables through the program representation.