FMIT facility control system

The control system for the Fusion Materials Irradiation Test (FMIT) Facility, under construction at Richland, Washington, uses current techniques in distributed processing to achieve responsiveness, maintainability and reliability. Developmental experience with the system on the FMIT Prototype Accelerator (FPA) being designed at the Los Alamos National Laboratory is described as a function of the system's design goals and details. The functional requirements of the FMIT control system dictated the use of a highly operator-responsive, display-oriented structure, using state-of-the-art console devices for man-machine communications. Further, current technology has allowed the movement of device-dependent tasks into the area traditionally occupied by remote input-output equipment; the system's dual central process computers communicate with remote communications nodes containing microcomputers that are architecturally similar to the top-level machines. The system has been designed to take advantage of commercially available hardware and software

Design and operation of the LAMPF Auxiliary Controller. High-speed remote processing on the CAMAC dataway

A CAMAC Auxiliary Controller has been developed to further the concepts of distributed processing in both process control and experiment data-acquisition systems. The Auxiliary Controller is built around a commercially available 16-bit microcomputer and a high-speed bit-sliced microprocessor capable of instruction execution times of 140 ns. The modular nature of the controller allows the user to tailor the controller capabilities to the system problem, while maintaining the interface techniques of the CAMAC Standard

Distributed control system for the FMIT

The control system for the Fusion Materials Irradiation Test (FMIT) Facility will provide the primary data acquisition, control, and interface components that integrate all of the individual FMIT systems into a functional facility. The control system consists of a distributed computer network, control consoles and instrumentation subsystems. The FMIT Facility will be started, operated and secured from a Central Control Room. All FMIT systems and experimental functions will be monitored from the Central Control Room. The data acquisition and control signals will be handled by a data communications network, which connects dual computers in the Central Control Room to the microcomputers in CAMAC crates near the various subsystems of the facility

Structural simplicity of the Zonula Occludens in the electrolyte secreting epithelium of the avian salt gland

The structure of the zonula occludens in the secretory epithelium of the salt gland of the domestic duck was determined by thin section and freeze-fracture electron microscopy. These glands secrete an effluent with a NaCl concentration four times that of plasma, and thus maintain a steep ionic gradient across their secretory epithelium. Freezefracture replicas from salt stressed ducks demonstrate that the zonula occludens is surprisingly shallow in depth (20–25 nm) and generally consists of two parallel junctional strands which are juxaposed along their entire length. In addition to the simplicity of the junction separating mucosal and serosal compartments, the ratio of junctional length to apical surface area is large since luminal surfaces of secretory cells are narrow and intermesh with one another. The zonula occludens in nonsecreting fresh water-adapted birds is similar to the salt stressed group except that two sets of double strand junctions are seen in addition to junctions consisting of a single set. Based on previous ultrastructural, cytochemical and physiological studies in salt glands and in other epithelia, a model for salt secretion was suggested in which intercellular space Na + , generated by basolateral ouabain-sensitive Na + pumps, reaches the lumen via a paracellular route (Ernst & Mills, 1977, J. Cell Biol. 75 :74). The simplicity of the morphological appearance of the zonula occludens in the salt gland, which resembles that described for several epithelia known to be leaky to ions, is consistent with this hypothesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48028/1/232_2005_Article_BF01869292.pd