55 research outputs found

    Analysis of retrofitted corroded steel pipes using internally bonded FRP composite repair systems

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    Steel pipelines play an important role in the oil and gas industry. Hence corrosion of the steel pipe systems during its service life is a critical issue for the industry. Fibre reinforced composites offer solutions with broad applicability and efficiency for the internal repair of these corroded pipelines. Understanding the behaviour of internal composite repair systems against different internal pressure regimes is an important aspect in the development of a repair system. This study develops the analyses of internal composite bonded repair systems for long steel pipes with an axisymmetric defect, based on Lame’s equation. Various levels of bonding between the steel and composite are studied. Fully bonded optimum internal composite repair thicknesses are determined using biaxial carbon and glass fibre composites for different levels of corrosions, using the Von Mises yielding and Tsai-Hill failure criterion approaches. Two case studies are illustrated using the design nomographs. The analysis technique used was found to be accurate when compared with finite element modelling results

    Preliminary study on herpetofaunal diversity of Nilgala forest area in Monaragala district, Sri Lanka

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    Nilgala ForestArea (NFA) is one of the largest and important forest area in Monaragala District, UvaProvince. It contain 12,432 hectares and lies within 7° 08' - 7° 14' NL and 81 D 16' - 81020' EL. Itselevation range between 200m to 700m within the Irindahela, Hangale, Yakun hela (highest point 700rn), Hamapola, Badangarnuwa, Keenagoda, Makada, Karadugala, Kukulagoda, Ewalahela, Gorikkadahills. The mean annual rainfall varies between where the average annual rainfall 1500mm - 2000mm(rain during northeast monsoon). while the mean annual temperature of the area is 28 DC - 31°C.The vegetation comprised with lowland tropical moist semi evergreen forest and savannah forest,home gardens and small patch paddy cultivations. The dominant tree species are Aralu (Terminaliachebulav, Bulu iTerminalia bellirica) and Nelli iPhyllanthus emblicay. Other than biodiversity,Nilgala is rich of archaeological monuments, such as prehistoric, proto-historic and historical Buddhistmonasteries.During the two-year study period, total number of 70 reptile species were and 19 amphibian speciesrecorded. Reptiles include 44 genera of 17 families and 20 (28.5%) endemic species. Amphibianfauna contain 13 genera including 4 families and 6 (31.5%) endemic species. 41.4% (29) of reptilesand 26.3% (5) of Amphibians listed as 'Nationally Threatened' in the 1999 IUCN National threatenedlist. Out of70 species 38 (54.2%) are Serpentoid reptiles (11 endemics) and 32 (45.7%) species areof Tetrapod reptiles (9 endemics). Among the recorded species, 11 Serpentoid, 3 Tetrapod, and 2amphibians have not been recorded by previous workers. Furthermore seven unidentified specieswere also recorded during the survey, which probably include new amphibian species belonging togenus Nannophrys. Human activities such as man-made fire, ilIegallogging, extensive use of chemicalsfor agriculture, forest clearing for chena cultivation and road kills were identified as a main threat forthe natural habitats as well as faunal species.

    A European Perspective on Auditory Processing Disorder-Current Knowledge and Future Research Focus

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    Current notions of “hearing impairment,” as reflected in clinical audiological practice, do not acknowledge the needs of individuals who have normal hearing pure tone sensitivity but who experience auditory processing difficulties in everyday life that are indexed by reduced performance in other more sophisticated audiometric tests such as speech audiometry in noise or complex non-speech sound perception. This disorder, defined as “Auditory Processing Disorder” (APD) or “Central Auditory Processing Disorder” is classified in the current tenth version of the International Classification of diseases as H93.25 and in the forthcoming beta eleventh version. APDs may have detrimental effects on the affected individual, with low esteem, anxiety, and depression, and symptoms may remain into adulthood. These disorders may interfere with learning per se and with communication, social, emotional, and academic-work aspects of life. The objective of the present paper is to define a baseline European APD consensus formulated by experienced clinicians and researchers in this specific field of human auditory science. A secondary aim is to identify issues that future research needs to address in order to further clarify the nature of APD and thus assist in optimum diagnosis and evidence-based management. This European consensus presents the main symptoms, conditions, and specific medical history elements that should lead to auditory processing evaluation. Consensus on definition of the disorder, optimum diagnostic pathway, and appropriate management are highlighted alongside a perspective on future research focus
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