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Direct condition assessment (DCA) of pipelines in water, waste water, oil, or gas service is growing in popularity due to the fact that asset managers need to know the condition of their pipelines, in detail, to maintain them and extend their life. Knowing which DCA tool is best for a given type of pipeline is an important step in selecting the best technology. This paper discusses the attributes of in-line inspection (ILI) tools that utilize remote field technology (RFT), ultrasonic (UT), electromagnetic acoustic technology (EMAT), and magnetic flux leakage (MFL) tools and discusses the strengths and limitations of each.

The standard RFT (remote field testing) technique has been found feasible for identifying and sizing tube support plate (TSP) hole enlargement caused by corrosion or erosion. Finite element simulations and experimental studies have shown that detector energy output (DEO) of a single‐exciter RFT probe is a linear function of the TSP‐tube gap for the gap size range studied in this research. DEO can be used to quantify the gap.

A liquid crystal attenuator (LCA) operated as a variable neutral density filter has been attached to a charge-coupled device (CCD) imager to extend the dynamic range of a solid-state TV camera by an order of magnitude. Many applications are best served by a camera with a dynamic range of several thousand. For example, outside security systems must operate unattended with "dawn-to-dusk" lighting conditions. Although this can be achieved with available auto-iris lens assemblies, more elegant solutions which provide the small size, low power, high reliability advantages of solid state technology are now available. This paper will describe one such unique way of achieving these dynamic ranges using standard optics by making the CCD imager's glass cover a controllable neutral density filter. The liquid crystal attenuator's structure and theoretical properties for this application will be described along with measured transmittance. A small integrated TV camera which utilizes a "virtual-phase" CCD sensor coupled to a LCA will be described and test results for a number of the camera's optical and electrical parameters will be given. These include the following camera parameters: dynamic range, Modulation Transfer Function (MTF), spectral response, and uniformity. Also described will be circuitry which senses the ambient scene illuminance and automatically provides feedback signals to appropriately adjust the transmittance of the LCA. Finally, image photographs using this camera, under various scene illuminations, will be shown.

A new, high. resolution, highly versatile CCD camera for industrial inspection applications is described. This camera is the second in a series of modular cameras (the first, A Modular TV Camera, was reported in 1979), and can be operated in the staring mode or in the scanning (TDI) mode. This paper describes the basic building blocks used to fabricate the camera, as well as a new 1904 x 48 virtual phase CCD sensor. Data relating to the performance of the sensor and the complete camera is presented.

The Bulletin of Zoological Nomenclature, Volume 25, Issue 4-5, pp. 165

The Bulletin of Zoological Nomenclature, Volume 21, Issue 5, pp. 363