[en] Purpose: To enable control rod insertion and extraction in a predetermined time with no effects from pressure variations in the reactor. Constitution: The pressure conditions in the reactor are detected by a pressure generator and the detected value is inputted to a pressure compensator. An adequate signal corresponding to the changes in the flow rate resulted from the changes in the reactor pressure is set and compensated in the pressure compensator. The proportional gain in a flow rate indication regulator is thus made pressure-dependent and the total gain can be obtained always at a certain level irrespective of the reactor pressure. (Ikeda, J.)

[en] A method of containing oil or like spillage floating on the surface of the sea or other waterway is described. It is achieved by means of a disposable self inflating boom assembly which is launched into the sea. Inflation of the assembly via control valves and supply lines is from a gas supply module, and both are launched from within a mobile assembly or container on a ship, platform, helicopter or by parachute from an aeroplane. Gas may be supplied from compressed gas cylinders, or by chemical reaction on contact with water, or from an air compressor or blower. Various arrangements of boom are described including having a membrane to create separately inflatable compartments, having at least one lower skirt, and using two adjacent boom assemblies. When the containment operation is completed the boom is recovered from the sea, cleaned and disposed of. (Author)

[en] The author briefly described the design, basic functions and implementation of an optimization control program for beam transport system of accelerator. The program has been used for the new heavy ion accelerator facility SIS in GSI, Germany and satisfying results are obtained

[en] Over the last decade, many energy experts have supported carbon sequestration as a viable technological response to climate change. Given the potential importance of sequestration in US energy policy, what might explain the views of communities that may be directly impacted by the siting of this technology? To answer this question, we conducted focus groups in two communities who were potentially pilot project sites for California's DOE-funded West Coast Regional Partnership (WESTCARB). We find that communities want a voice in defining the risks to be mitigated as well as the justice of the procedures by which the technology is implemented. We argue that a community's sense of empowerment is key to understanding its range of carbon sequestration opinions, where 'empowerment' includes the ability to mitigate community-defined risks of the technology. This sense of empowerment protects the community against the downside risk of government or corporate neglect, a risk that is rarely identified in risk assessments but that should be factored into assessment and communication strategies.

[en] This paper describes a Supervisory Control and Data Acquisitioning system called SCADA that we have developed at NUST. This research is aimed at the development of a network where a central Control Server extends bidirectional data exchange capability to hundreds of geographically remote sensors and actuators spread over a distance greater than 3 Km. Several battery-driven handheld terminals called Remote Terminal Units (RTU) have been designed to provide both wired and wireless connectivity between sensors and the network, also adding limited mobility to the sensors. Simple transceivers give the RTUs wireless access to network. The Human-Machine Intel (HMI) for the RTUs and the Server have been provided. A repeater has also been designed to increase the number of RTUs connected, and the maximum allowed distance between units and the server. The wired network gives several times faster connectivity than the wireless network, in addition to the larger area covered, but at the cost of mobility. (author)

[en] This paper describes a distributed embedded system that uses a high performance mixed signal controller C8051F040 for its DAQ nodes and is based on CAN bus protocol for remote monitoring and controlling of various subsystems of 750 KeV DC accelerator based irradiation facility at RRCAT, Indore. A PC with integrated PCI CAN card communicates with intelligent DAQ nodes over CAN bus and each node is interfaced with a subsystem. An opto isolated SN65HVD230 CAN driver is interfaced between each node and physical bus. Remote frames and message prioritising are used for efficient control. The PC application is developed using LabVIEW 8.6. The proposed system is more reliable and noise immune as compared to previously used systems that initially used a centralized system based on C8051 controller. This was then upgraded to a distributed system that used microcontroller AduC812 and communicated over RS485 link. The new system has been integrated and tested satisfactorily for its designed performance with test jigs that simulated the actual subsystems with a bus length of 75 meters. First the complete scheme of the system is presented, and then the hardware and software designs are discussed. (author)

[en] The groundings of the Exxon Valdez on Bligh Reef in Prince William Sound, spilling more than 10 million gallons of Alaska North Slope crude, and the American Trader off Huntington Beach, spilling almost 400,000 gallons of Alaska North Slope crude, suggest that the construction of oil tankers be re-examined with respect to a design which could reduce both the number and magnitude of oil spills. This paper discusses state-of-the-art tanker technology with respect to spill prevention, effectiveness, and cost. The design features include double hulls, centralized bunker tankers, vacuum-retaining valves, cargo control systems, auxiliary thrusters, electronic charting, and the retransmission of the ship's position. Double hulls provide the highest probability of surviving damage, either from a collision or grounding, with no loss of cargo. Use of double hulls can reduce oil spill incidence by 90 percent in grounding situations and by 75 percent in collisions. The oil spill from the AmericanTrader could have been completely avoided by double hull construction. The arrangement provides spaces below the cargo tanks and on the vessel's sides solely for the carriage of ballast water when the tanker is in ballast condition. These tanks are empty when the tanker is loaded and then also act as the first line of defense in the event of structural damage to the cargo tanks. Tanker design is integrated with port safety measures, including vessel monitoring systems, in this total spill prevention analysis. All aspects of the tanker transportation system are considered

[en] The mythological character Icarus had the misfortune of learning the consequences of his decision to fly too near the sun at the same time he employed his decision. Although Daedalus tried to reduce the uncertainties of his son's decision by warning Icarus of the possible outcome, Icarus had no empirical knowledge of what would actually happen until his waxen wings melted and he fell to the sea. Like Icarus, man has no empirical knowledge or conclusive evidence today of the possible effects of global climate change. And though the consequences of policy decisions toward global climate change may not be as catastrophic as falling into the sea, the social and economic impacts of those decisions will be substantial. There are broad uncertainties related to the scientific and ecological aspects of global climate change. But clearly the ''politics'' of global climate change issues are moving at a faster rate than the science. There is a public outcry for action now, in the face of uncertainty. This paper profiles a case study of a southwestern utility's use of multi-attribute preference theory to reduce uncertainties and analyze its options for addressing global climate change issues

[en] The dynamic period equation gives the instantaneous reactor period as a function of the reactivity and the rate of change of reactivity. An alternate formulation of this equation, together with the details of its derivation from the point kinetics equations, is presented. The advantages of this alternate formulation relative to the standard one are that the derivation is not dependent on the prompt-jump approximation and that each term in the resulting equation can be readily calculated in real-time. An evaluation is then given of the behavior of each of the component terms of this alternate equation as a function of reactivity. The use of this alternate dynamic period equation for the design and operation of a non-linear, closed-loop, digital controller for a nuclear reactor is then described. Details of initial experimental trials of the resulting controller are given. This alternate controller, which is structured in accordance with the reactivity constraint approach to reactor control, is shown to be an effective and reliable means for accomplishing changes in the reactor power

[en] The linear electron accelerator thermostat systems have been experimentally investigated using a programmed controller, controlled thyristor units, and necessary computer software. The processes for settling the thermostat temperature with controlled heating power (up to 7 - 10 kVa) that is used in the 'training' and operating modes of the radio-frequency accelerator section of LUE-40 were observed. The control-system dynamics with varying RF power and thermostat cooling is also shown. The program controlling process made it possible to decrease the settling time and temperature stability error to 0.05 deg C. (author)