State (computer science)

About: State (computer science) is a research topic. Over the lifetime, 24436 publications have been published within this topic receiving 225733 citations.

Regular Ternary Logic Functions—Ternary Logic Functions Suitable for Treating Ambiguity

Abstract: A special group of ternary functions, called regular ternary logic functions, are defined. These functions are useful in switching theory, programming languages, algorithm theory, and many other fields—if we are concerned with the indefinite state in such fields. This correspondence describes the fundamental properties and representations of the regular ternary logic functions.

Periodic Event-Triggered Synchronization of Linear Multi-Agent Systems With Communication Delays

Abstract: Multi-agent systems' cooperation to achieve global goals is usually limited by sensing, actuation, and communication issues. At the local level, continuous measurement and actuation is only approximated by the use of digital mechanisms that measure and process information in order to compute and update new control input values at discrete time instants. Interaction with other agents takes place, in general, through a digital communication channel with limited bandwidth where transmission of continuous-time signals is not possible. This technical note considers the problem of consensus (or synchronization of state trajectories) of multi-agent systems that are described by general linear dynamics and are connected using undirected graphs. The proposed event-triggered consensus protocol not only avoids the need for continuous communication between agents but also provides a decentralized method for transmission of information in the presence of time-varying communication delays, where each agent decides its own broadcasting time instants based only on local information. This method gives more flexibility for scheduling information broadcasting compared to periodic and sampled-data implementations.

Modular Verification of Computer Communication Protocols

Abstract: Programs that implement computer communications protocols can exhibit extremely complicated behavior, and neither informal reasoning nor testing is reliable enough to establish their correctness. In this paper we discuss the application of modular program verification techniques to protocols. This approach is more reliable than informal reasoning, but has an advantage over formal reasoning based on finite-state models, the complexity of the proof need not grow unmanageably as the size of the program increases. Certain tools of concurrent program verification that are especially useful for protocols are presented, history variables that record sequences of input and output values, temporal logic for expressing properties that must hold in a future system state such as eventual receipt of a message), and module specification and composition rules. The use of these techniques is illustrated by verifying two data transfer protocols from the literature: the alternating bit protocol and a protocol proposed by Stenning.

Memory bus termination with memory unit having termination control

Abstract: Methods and apparatus for a memory system using line termination circuits in each memory unit (e.g., integrated circuit memory device) are disclosed. The memory unit contains termination control logic that sets the state of a controllable termination circuit to control reflections on the data bus. The termination control logic determines the proper state for the termination circuit from the state of its memory unit, and in some cases, from the approximate state of the data bus as gleaned from commands decoded from the command/address bus. A termination configuration register on the unit can be used to define the appropriate termination state for each unit state and/or data bus state.