Informatics Publishing Limited

N. Sridharan , S. Somasundaram , K. Thiyakesan , Lalitha Vijayan

Abstract

Wetlands are important bird habitats and are also used by local people for their livelihoods. Study was undertaken to assess the status of the wetland birds in the selected wetlands by using total count method during January-March 2006. Forty two major wetlands were surveyed in four districts of Tamilnadu namely Kanyakumari, Thanjavur, Cuddalore and Nagapattinam. Totally 15,616 individual birds belonging to 65 species of 31 families were recorded. Out of the 65 species recorded, 42 were wetland and 23 were terrestrial species. The most common bird family in the study area was Ardeidae (Commonness index=0.33) followed by Anatidae (Commonness index=0.27). One threatened and two near threatened species namely, spot-billed pelican (Pelicanus philippensis) (VU), painted stork (Mycteria leucocephala) (NT) and darter (Anhinga melanogaster) (NT) were recorded.

Keywords

Wetland, Water Birds, Ardeidae, Tamil Nadu, Conservation

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K. S. Sathyanarayanan ¹, N. Sridharan ¹

Affiliations
1 Department of Civil Engineering, SRM University, Chengalpattu, Kancheepuram District - 603203, Tamil Nadu, IN

Abstract

Background/Objective: To find an easy method to health monitor structures. Method: Self sensing or smart behavior has been observed in mortar or concrete with the addition of small amounts (0.2 to 0.5% by volume of cement) of short (5mm length) carbon fibres. It is seen that there is an increase in electrical resistance on loading upto crack propagation or fracture. On reaching the inelastic stage, the resistance change is not reversible. Findings: A method is developed which can be used in place of, often used strain gage technique or fibre optic technique for health monitoring of structures. There is an increase in resistance during fibre pull out in the elastic range. The change in elastic resistance was measured by a four probe method and was seen to be reversible for elastic deformation. Also, the crack propagation and fibre breakage of the specimen can be identified by irreversible resistance change. The stress vs strain and resistance vs strain graphs when plotted show similarity. Application: This phenomenon can be made use of to find the real time weight of vehicles in traffic and finding stress values of a loaded structure etc.

Keywords

Carbon Fibre, Health, Monitoring, Resistance-Strain, Sensor, Stress-Strain

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