Iconic Display Research Articles

Situation Awareness: Icons vs. Alphanumerics

This study examined the effect of varying the amount of information that is presented in either an alphanumeric or iconic display and its effect on how efficiently a pilot can utilize the data. The results from 12 subjects, under self-paced presentation length conditions, indicated that for a small quantity of data (2 or 4 bits) there is no difference in response times between iconic and alphanumeric displays. As the quantity of data presented increases (8, 16, or 32 bits), subjects perform better using iconic displays.

A Direct Manipulation Interface for Water-Based Rankine Cycle Heat Engines

A concept for a direct manipulation interface to monitor and control water-based Rankine cycle heat engines is discussed and illustrated. The computer-driven interface utilizes measured plant data to form a model of the process. The model is presented in the form of an icon based upon the Rankine cycle. The icon is formed in terms of the temperature and entropy properties of water from various points within the Rankine cycle. In addition, real-time mimics of plant systems, which contain, control, and interact with the process, are presented within the same display format. The image displayed (on a cathode-ray tube) is designated a system-process iconic display of plant operations. An inference engine driven by plant data updates the display of plant segments which compose the iconic display. The iconic display serves as a visual knowledge base of plant operation as the interface is based on a model-world metaphor. A keyboard containing dedicated control keys serves as an interface to actuate control tasks allocated to human operators. A direct manipulation of the heat engine is achieved through the dedicated keys as the icon responds to plant reactions activated by the control tasks. The human operator evaluates the data presented in the system-process iconic display to determine if the goals of operation are being met. The workload imposed upon human operators to assess goals is minimized, making the human operator an effective supervisor of resources and also an active integrated member of plant operations.

Iconic Displays, Rankine Cycles and Human Factors for Control Rooms of Nuclear Power Plants

This report discusses a concept for a nuclear power plant (NPP) process iconic display to model the plant in the control room of a pressurized-water reactor (PWR). The iconic display is based on the Rankine Cycle, a thermodynamic model for the power cycle. The display image contains coded information on the generation, transport, and removal of heat in the power plant process. It is useful in evaluating both steady-state and transient operation in the power plant. Elements within the display image become distorted during many of the significant design-basis accidents thus facilitating operator recognition of these events. The iconic display serves as an overview monitor of the plant process. It structures and codes temperature and pressure sensor data into a synthesis of the heat transfer process from the heat source, the reactor core, to the heat sink, the environment. With this coded information in the form of patterns that can be easily interpreted by the operator, the operator's data search time, dwell time, and data processing workload are minimized, thus enhancing the probability that the operator will make correct decisions and minimizing the probability of errors.