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The design, manufacture, and commissioning of a global positioning system enabled sampler instrument conceived for the retrieval of seabed sediments are described. This system was designed for sampling in environmental assessment applications and, especially, those requirements that might include insoluble, anthropogenic radioactivity derived from the effluent from nuclear facilities. Once triggered, the sampler operates autonomously for the recovery of samples by settling in the sampling environment, and it is compatible with submersion in fresh water and also with an off-the-shelf, submersible, remotely operated vehicle. A number of tests have been carried out to determine the efficiency and efficacy of the sample recovery performed by the system and the extent to which the recovery of samples disturbs neighboring sediments.

The design, manufacture, and commissioning of a global positioning system enabled sampler instrument conceived for the retrieval of seabed sediments are described. This system was designed for sampling in environmental assessment applications and, especially, those requirements that might include insoluble, anthropogenic radioactivity derived from the effluent from nuclear facilities. Once triggered, the sampler operates autonomously for the recovery of samples by settling in the sampling environment, and it is compatible with submersion in fresh water and also with an off-the-shelf, submersible, remotely operated vehicle. A number of tests have been carried out to determine the efficiency and efficacy of the sample recovery performed by the system and the extent to which the recovery of samples disturbs neighboring sediments.

To decommission the Fukushima nuclear power plant after the accident caused by a tsunami in 2011, characterization of the fuel debris is required. The precise location and radiological composition of the fuel debris are currently unknown, and the area is submerged making it difficult to investigate the primary containment vessel. An integrated system that includes both radiation detectors and sonar will allow the full localization and characterization of the fuel debris. This paper describes research completed toward the development of a complete system, on-board a low-cost, small form-factor, submersible remotely operated vehicle. A cerium bromide (CeBr3) scintillator detector for dose-rate monitoring and gamma-ray spectrometry has been integrated and validated experimentally with a 137Cs source, both in the laboratory and while submerged. The addition of an Imagenex 831L sonar has enabled technical demonstrations to take place at the National Maritime Research Institute's facility in Japan, where the system was able to characterize the shape and size of synthetic core debris. The combination of geometrical and radiological measurements allows the real-time localization of fuel debris and isotope identification, leading to an invaluable source of information to the workers at Fukushima that will enable increased efficiency and reduce risk during the decommissioning of the site.

We have performed combined digital imaging of neutrons and gamma rays in mixed radiation fields. An organic liquid fast scintillation detector has been integrated into a system with a digitizer, collimator and an equatorial mount to characterize two mixed-field environments. Images have been produced corresponding to the angular distribution of events and the three-dimensional Cartesian coordinate system for both gamma rays and neutrons, simultaneously. These data indicate that mixed fields can be readily imaged with a single detector in terms of their gamma-ray and neutron components at the same time.

The research scheme proposed in this article describes the development of a PC-based teaching/learning approach to power systems education. The paper describes an illustrative network system to be modelled and the software’s capabilities and features, as implemented using MatLab. Simulation functions are introduced for teaching and learning purposes, in order to help students better understand complex electromagnetic transient phenomena of electrical power systems under various system fault conditions. The teaching impact of the simulator is discussed, with a focus on how students using this approach are supported with regard to developing their skill set, transferable knowledge and future career. The work demonstrates that adopting such an innovative simulation approach can allow for rapid simulation-based experimentation, and facilitates student learning in a safe and cost-effective environment, particularly where practical student experience is not otherwise feasible.

The design of a portable three-band cosmic-ray neutron detector is reported in this article. This instrument has been designed to characterise cosmic: ray neutron fields in the upper atmosphere and in cosmic reference field facilities. The design utilises a spherical moderator with a layer of spallation material covering a central He-3 proportional counter. The instrument incorporates twelve lithium-coated diodes, six on the outside of the polyethylene layer and six placed within the structure. The dimensions, materials and arrangement of these in the instrument have been optimised with MCNPX to provide a compromise between the requirements of portability and spectral response.