Conceptual design of a computer-driven display for monitoringreactor coolant mass

The conceptual design of a display for monitoring reactor coolant mass in the primary coolant loop of a pressurized water reactor is discussed. A means-end relational network serves as the framework for decomposing the abstract-the conservation law of mass-into system and process variables. A computer-driven display synthesizes, in real time, mass sources, mass inventory, and mass sinks based on measured plant variables. The purpose of the display is to aid human users in the cognitive tasks of monitoring operations, diagnosing system faults, and responding to component and system failures that affect mass     

Plant and safety system model

The design and development of a digital computer-based safety system for a nuclear power plant is a complex process. The process of design and product development must result in a final product free of critical errors; operational safety of nuclear power plants must not be compromised. This paper focuses on the development of a safety system model to assist designers, developers, and regulators in establishing and evaluating requirements for a digital computer-based safety system. The model addresses hardware, software, and human elements for use in the requirements definition process. The purpose of the safety system model is to assist and serve as a guide to humans in the cognitive reasoning process of establishing requirements. The goals in the use of the model are to: (1) enhance the completeness of the requirements and (2) reduce the number of errors associated with the requirements definition phase of a project.     

Energy, mass, model-based displays, and memory recall [PWRoperation]

The operation of PWR within the framework of the conservation laws for energy and mass is discussed. These conservation laws, which are the basis of the Rankine heat-engine cycle, are used to generate a computer-graphic icon of the heat-engine cycle in terms of temperature-entropy coordinates for water. This icon then serves as a model-based display of the plant process. A human user is then able to exercise a plant monitoring strategy based on the conservation laws. The model-based display consists of a process icon and a system icon. The theoretical basis of the process icon rests with the fundamental laws of thermodynamics. The system icon synthesizes the operation of plant water systems that interact with the process. The results of an analysis on a PWR utilizing the fundamental laws of thermodynamics identify the main variables for evaluating the process. A computer's synthesis of these process variables results in an articulation of the process in the form of a real-time model (on a cathode-ray tube) of the cycle     

An expert display system and nuclear power plant control rooms

General topics for consideration when designing expert display systems and nuclear power plant control room displays are summarized. A system is proposed in which the display of segments (a combined series of graphic primitives or a reusable collection of graphic primitives and primitives attributes stored in memory) controls a cathode-ray-tube's screen to form an image of plant operations. The image consists of an icon of: (1) the process (heat engine cycle), (2) plant control systems, and (3) safety systems. A set of data-driven, forward-chaining computer-stored rules control the display segments. As plant operation changes, measured plant data are processed through the rules, and the results control the deletion and addition of segments to the display format. The icon contains information needed by control rooms operators to monitor plant operations. One example of an expert display is illustrated for the operator's task of monitoring leakage from a safety valve in a steam line of a boiling water reactor (BWR). In another example, the use of an expert display to monitor plant operations during pre-trip, trip, and post-trip operations is discussed as a universal display