Vessel maintenance requires periodic visual inspection of the hull in order to detect typical defective situations of steel structures such as, among others, coating breakdown and corrosion. These inspections are typically performed by well-trained surveyors at great cost because of the need for providing access means (e.g., scaffolding and/or cherry pickers) that allow the inspector to be at a...

Nondestructive evaluation methods are widely used in quality control processes for critical components in systems such as aircraft engines and nuclear power plants. These same methods are also used in periodic field inspection to assure that the system continues to be reliable while it is in service. This paper describes a detection algorithm to automatically analyze vibrothermography sequence-...

This paper is to propose a two-stage preventive maintenance (PM) policy for the multi-state deterioration system under periodic inspection and with multiple candidate actions for PM. Such policy is mainly to schedule PM optimally and also on how to choose the action optimally for each PM. The scheduling includes two tasks: to determine after completing each PM when to make the decision and then...

The few remarks I purpose making this evening are concerned with the health of children at public and private boarding and day schools, and are in no way applicable to elementary or State-supported schools. In one way the latter class of school has a great advantage, inasmuch as they are subject to periodic medical inspection either by the medical officers of the Local Government Board, or by t...

Interval censored data arises when individuals can be subjected to periodic inspection at possibly random moments, and their status (e.g. failed or functioning) is ascertained at each inspection. We exploit the order theoretic properties of interval orders to develop a new language describing interval censored data. We show that inference can be based on the set Mof maximal antichains of the da...

Thermal wave inspection techniques utilise controlled heat diffusion to probe the surface and subsurface structure of a component [1-3]. Various techniques have been developed which use localised intensity or spatially modulated laser heating for thermal wave generation [2] and a variety sensors, acoustic, optical, and thermal, for their detection [3,4]. The quantitative application of these te...

OBJECTIVE In order to safely manage nuclear power plants, their workforce should be mentally healthy. This study clarifies the coping strategies of radiation control personnel and nondestructive inspectors engaged in the periodic inspection of nuclear power plants, the effect of the coping strategies on their mental health, as well as any effect based on whether or not they had worked after the...

Nuclear reactors require periodic maintenance and inspection to ensure continued and safe operations, and automation of inspection tasks through robotics can minimize the duration of reactor inspection outages in a safe and costeffective manner. State-of-the-art reactor pressure vessel inspection leverages remotely operated vehicles (ROVs), which are teleoperated, submersible robots. In order t...

We show that, via temporal modulation, one can observe a high-speed periodic event well beyond the abilities of a low-frame rate camera. By strobing the exposure with unique sequences within the integration time of each frame, we take coded projections of dynamic events. From a sequence of such frames, we reconstruct a high-speed video of the high frequency periodic process. Strobing is used in...