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Killough, Stephen M.

Publications and source records attributed to Killough, Stephen M..

Criteria for Determining the Safety of Wireless Technologies at Nuclear Power Plants

This report provides an initial discussion of the potential impact to safety-related/important-to-safety (SR/ITS) systems by the possible expanded use of wireless technologies. One aspect of this discussion is focused on a review of Regulatory Guide (RG) 1.180 Rev. 2 to determine whether any revisions are necessary to reflect the current state of practice in evaluating and protecting instrumentation and control (I&C) systems and components from electromagnetic interference (EMI) or radiofrequency interference (RFI) on safety and nonsafety I&C. Electromagnetic compatibility (EMC) is the ability of a device or system to function satisfactorily in its electromagnetic (EM) environment, which is achieved by limiting the unintentional generation, propagation, and reception of EM energy that may cause unwanted effects such as EMI. The goal of EMC is to ensure the correct operation of different types of equipment in a common EM environment.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

On the Performance of Tree-Based Antennas for SLF-VLF Signal Reception

A full-wave electromagnetic simulation and experimental study is carried out to explore the effects of tree-induced dielectric loading on the receiving properties of an electrically small, earth-grounded wire monopole. It is demonstrated that by connecting the upper end of the wire to the tree trunk, the input impedance of the monopole can be significantly transformed, leading to an enhancement in the received signal strength that becomes more noticeable as the frequency is decreased; for example, at the lowest frequency considered, it is seen that the tree-loaded antenna can increase the received load voltage by as much as ~40 dB, when compared to the case without tree loading. An application of the tree-based antenna for low-frequency power line signal monitoring is presented. Overall, simulation results for the input impedance and received signal response are in good agreement with measurement data.

Liao, DaHan↗

Flexible sensor technology

A system and method (referred to as a method) to fabricate sensors and electronic circuits. The method prints a first thin-film having an electronic conductivity of about less than a millionth of a Siemens per meter and a permalloy directly onto the first thin-film. The permalloy has a magnetic permeability greater than a predetermined level and has a thickness within a range of about 1 to 20 microns. The system prints a second thin-film directly onto the permalloy to encapsulate the permalloy onto the first thin-film and prints conductive traces directly onto the surfaces of the first-thin-film, the permalloy, and the second thin-film. In some applications, a sensor is packaged in an additively manufactured three-dimensional cylindrical shape that can be mounted on or is a unitary part of a current carrying conductor without incising, sharing, or severing (e.g., cutting) the current carrying conductor or its insulation.

Joshi, Pooran Chandra↗

Development and demonstration of a telerobotic excavation system

Oak Ridge National Laboratory is developing remote excavation technologies for the Department of Energy's Office (DOE) of Technology Development, Robotics Technology Development Program, and also for the Department of Defense (DOD) Project Manager for Ammunition Logistics. This work is being done to meet the need for remote excavation and removal of radioactive and contaminated buried waste at several DOE sites and unexploded ordnance at DOD sites. System requirements are based on the need to uncover and remove waste from burial sites in a way that does not cause unnecessary personnel exposure or additional environmental contamination. Goals for the current project are to demonstrate dexterous control of a backhoe with force feedback and to implement robotic operations that will improve productivity. The Telerobotic Small Emplacement Excavator is a prototype system that incorporates the needed robotic and telerobotic capabilities on a commercially available platform. The ability to add remote dexterous teleoperation and robotic operating modes is intended to be adaptable to other commercially available excavator systems.

Burks, Barry L.↗