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Social media plays a major role in the propagation of information during disasters. This paper mainly contains a study regarding how people of Chennai used social media especially twitter, in response to the country’s worst flood that had occurred recently. The tweets collected were analysed using machine learning algorithms such as Random Forests, Naive Bayes and Decision Tree. By comparing the performances of all the three it was found that Random Forests is the best algorithm that can be relied on, during a disaster. This paper also targeted the sources of the Twitter messages to explore the most influential users of Chennai flood. [ABSTRACT FROM AUTHOR]

This paper discusses about the results of a short term monitoring study of sea coast contaminated with oil spill. Collision of two oil-cargo ships, namely BW Maple and MT Dawn Kanchipuram near the Ennore Port, Chennai had released an approximately 200 tonnes of heavy fuel oil. We analyzed four different oil spill samples collected from Chennai beaches for different time intervals (1st, 3rd, 6th, 10th day of oil spill) from 1 km away from the source of the off shore spill location. The physicochemical characteristics of spilled oil sludge, concentration of total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs) present in the spilled oil were investigated. The variations in pH, moisture content and volatile hydrocarbon content, viscosity and density of the spilled oil were in the range of 7 ± 0.2, 255–575 g/kg, 118 to 850 PaS and 1.04 to 0.98 g/cm3 respectively. Elemental analysis showed that C, H, N and S were in the range of 9.9–13.3 (%), 0.63 to 1.76 (%), 1.88 to 1.02 (%) and 0.29 to 0.27 (%) respectively. Analysis of oil spill samples using gas chromatography and mass spectrometry (GCMS) shows the presence of recalcitrant and hazardous PAHs such as fluoranthene and pyrene. Ocean sediments were collected at different locations along the coast line from Ennore to Cooum after 60 days of oil spill and analyzed for TPH in GCMS. The results showed that the residual concentrations of TPH varied from 0.19 to 3.43 mg/g. The presence of heavy PAHs, which are highly toxic and recalcitrant, could pose a severe threat to the marine environment and ecology.The long term effects of these compounds were unexplored on marine environment. This environmental monitoring study gives an overview about the post oil spill activities and steps taken to remediate the sludge along the coastline. Image 1 • This study highlights the immediate fate and characteristics of the Chennai oil spill over a short period. • Total petroleum hydrocarbon concentration increased from third day to sixth day and then stabilized. • Viscosity of the spilled oil increased eight times from day1 to day 10 after the oil spill. • Priority pollutants such as Fluoranthene and pyrene were identified in beach sediments using GC-MS. [ABSTRACT FROM AUTHOR]

Abstract: In India the emissions rate and fuel consumption of intra-city buses are estimated using the European driving cycles, which don’t represent Indian driving conditions and in-use operation of vehicles. This leads to underestimation or overestimation of emissions and fuel consumption. In this context, this paper offers some insight into the driving characteristics of intra-city buses using a Global Positioning System. The study has revealed that irrespective of road type and time of travel, a higher percentage of time is spent in idle mode. This is primarily due to alighting and boarding of passengers at regular intervals and fixed delays caused by traffic lights. More than 90 percent of trips have an average speed of less than 30 km h−1. This study has also developed an intra-city bus driving cycle for Chennai and compared it with some well-known international driving cycles. It has revealed that Chennai has unique driving characteristics and, therefore, it may not be appropriate to adopt a driving cycle of another country or city. [Copyright &y& Elsevier]

Abstract: This paper presents different types of premature failures observed during full-scale testing of Transmission line towers at Tower Testing and Research Station, Structural Engineering Research Centre, Chennai. Failures that have been observed during testing are studied and the reasons are discussed in detail. The effect of non-triangulated hip bracing pattern and isolated hip bracings connected to elevation redundants in ‘K’ and ‘X’ braced panels, on tower behaviour are studied. The tower members are modeled using beam-column and plate elements. Different types of failures are modeled using finite element software and the analytical results and the test results are compared with various codal provisions. The non-linear finite element analysis program NE-NASTRAN has been used to model the elasto-plastic behaviour of towers. Importance of secondary member design and connection detail in overall performance of the tower was studied. Non-linear finite element analysis is useful in understanding the system behaviour and for prediction of failure pattern and ultimate load. Based on the test results the importance of studying the failures is highlighted. The need for testing of transmission line towers is emphasized. [Copyright &y& Elsevier]

Abstract: Background: Locked pubic symphysis is an unusual form of pelvic injury. In this the intact pubis gets trapped against contralateral pubis. Closed reduction can be attempted though often requires open reduction and internal fixation. This paper is presented for its rarity and probably first case series on locked pubic symphysis from single institute. Materials and methods: Three cases are presented from the Institute of Orthopaedics and Traumatology, Government General Hospital and Madras Medical College, Chennai from February 2007 to July 2009. Initially closed reduction was attempted but was not possible, so open reduction was planned. Open reduction was successful in all cases with some difficulty and fixed with symphysial plating. All patients were followed up for functional outcome for a mean follow-up of 15 months. Discussion: This is the first time in the literature a case series of locked pubic symphysis is presented. In all cases it was found that anterior superior iliac spine on the affected side had moved closer to the midline compared to the opposite side. Though suprapubic cystostomy is a contraindication for pfannensteil incision, we have reduced three cases by this incision and done internal fixation with no postoperative wound infection. We were able to reduce the locked pubis with simple maneuvers and with no special distraction instruments. We did not require any osteotomy for the reduction which is a disadvantage as it may produce healing problems. Conclusion: Locked pubic symphysis is a rare form of pelvic injury. Though conservative closed reduction maneuvers have been described open reduction is often required. Internal fixation helps not only in stabilizing the anterior rim of pelvis but also the posterior aspect by stabilizing the sacro iliac joint which improves pelvic stability and promotes recovery. [Copyright &y& Elsevier]

Abstract: The newly constructed port in 2001 at Ennore, on the southeast coast of India near Chennai, with breakwaters on either side (north and south) has been causing large-scale changes in nearshore morphology. Beach profiles and shoreline positions along 25 km coastline of Ennore were measured at regular intervals during 2001–06 to understand the sediment transport patterns in the region. At the same time the results of wave hind-casting and wave transformation modeling were incorporated in LITDRIFT model to compute the sediment transport rates along Ennore coast. The model results are compared with the sediment transport values obtained from beach profile measurements. The performance of the model at different locations within the study area with variable wave conditions has been examined. The annual net sediment loss (−) versus accumulation (+) were estimated for two smaller study areas (cells) containing ten regularly spaced beach profiles numbered from north to south, BP1-5 in cell I and BP6-10 in cell II. For the cell I region, which is protected by the Ennore shoals and where human interference is minimum, the annual net sediment supply is +0.02×106 m3 as obtained from beach profile measurements while the model gave a value of +0.014×106 m3. For the cell II region where there is large human intervention by way of Ennore port development and breakwater construction, the annual net sediment movement as obtained by the beach measurements is −0.14×106 m3 while the model gave a value of −0.154×106 m3. It is found that the performance of the model is satisfactory and the model may be used successfully to study sediment dynamics along any coastline provided one has detailed understanding of the coastline orientation, nearshore topography, cross-shore bathymetry and prevailing annual wave climate. Based on the sediment transport data and beach profile measurements the beach and shoreline changes for transect locations BP-1 to BP-10 are also critically examined in this paper. [Copyright &y& Elsevier]