Faculty Publications
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Item WAVE FORECASTING FOR THE WEST COAST OF IHDIA(American Society of Civil Engineers (ASCE), 1970) Dattatri, J.; Renukaradhya, P.S.The applicability of the general Wave Forecasting procedures like the SMB and the PNJ methods, to the Indian coasts is studied. The study consisted in analysing the bynoptic charts to obtain the necessary wind characteristics. The computed wind characteristics were used in the above Forecasting methods to yield significant wave heights These were compared with the wave characteristics as recorded by a sub-surface pressure type recorder after suitable modifications to account for the attenuation of wave pressure with depth. The predicted wave heights compare well with the recorded wave heights and the SMB method predicts wave heights better for the case studied. © 1970 American Society of Civil Engineers.Item FIELD STUDY OP SURATHKAL BEACH(American Society of Civil Engineers (ASCE), 1970) Suryaprakasa Rao, P.; Kassim, P.Beach profile observations and sediment sampling were carried out for six months at frequent intervals to study the seasonal changes of the beach. Iht study is helpful in bringing out the qualitative and quantitative changes of the beach under varying wave and tide conditions. Useful information is obtained and presented regarding i) the maximum rate of erosion ii) the total quantity of material eroded iii) the critical wave steepness values which changed from depositing to eroding nature and iv) the sediment characteristics of the beach. © 1970 American Society of Civil Engineers.Item Overtaking behaviour of vehicles on undivided roads under mixed traffic conditions(Hong Kong Society for Transportation Studies Limited general@transportmetrica.org, 2015) Asaithambi, G.; Shravani, G.Overtaking is one of the most complex and important manoeuvre on undivided roads where the vehicles use the opposing lane to overtake the slower vehicles with the presence of oncoming vehicles from opposite direction. This process involves lane-change manoeuvres, acceleration and deceleration actions and estimation of relative speed of overtaking and overtaken vehicles, and also, estimation of speed and distance of the oncoming vehicle. Traffic on Indian roads is highly mixed in nature with widely varying static and dynamic characteristics of vehicles. These vehicles do not follow strict lane discipline and occupy any available lateral position on the road space. In the present study, details of overtaking data is collected on a two-lane two-way rural road using moving car observer method and registration plate method and overtaking characteristics of all types of vehicles under mixed traffic conditions are observed and mathematically modelled. Two types of overtaking strategies are observed in the field such as flying and overtaking. Graphs are plotted between the relative speed of the overtaking and overtaken vehicles against the overtaking time and negative correlation is found between the speed differential for all categories of vehicles and the total overtaking time. It was found the increase in flow rate causes an increase in demand of passing and decrease in passing supply.Item Climatic effects on sugarcane productivity in India: A stochastic production function application(Inderscience Publishers, 2015) Singh, A.; Sharma, P.; Ambrammal, S.K.The present study estimates the influence of climatic and non-climatic factors on mean yield and yield variability of sugarcane crop in different weather seasons (e.g., rainy, winter and summer) in India. Sugarcane mean-yield for fourteen major sugarcane growing states from different agro-ecological zones are delimitated in panel data during 1971-2009. Regression coefficient for mean yield and yield variability production function (i.e. risk increasing or decreasing inputs) has been estimated through log-linear regression model with the help of Just and Pope (stochastic) production function specification. Empirical results based on feasible generalise least square (FGLS) estimations shows a significant effect of rainfall, maximum and minimum temperatures on sugarcane mean yield and yield variability. Whereas, average maximum temperature in summer and average minimum temperature in rainy season have a negative and statistically significant impact on sugarcane mean yield. Sugarcane mean yield positively gets affected with average maximum temperature during rainy and winter season. © © 2015 Inderscience Enterprises Ltd.Item E-learning services: Insights from Twitter Analytics(Institute of Electrical and Electronics Engineers Inc., 2019) Vanitha, P.S.; Alathur, S.Electronic learning is a formalized teaching-learning service using electronic resources. With the help of Information and Communication Technologies (ICTs), knowledge can be shared via the Internet anywhere, anytime. Although, the massive growth of technologies available, e-learning service may not distribute equally in developing countries like India. The objective of the study is to explore the technological challenges of e-learning services in the Indian context. In the present study, the real-Time feedback about the technological challenges is collected directly from Twitter social media. Initially, the tweets were extracted based on the hashtags, and the location-based analysis is performed using geocoding. In this study, various types of technological challenges are identified, and the most influential factor is determined. It gives better results when this research is carried on developing countries like India. The suggestion provided in this research will help to decrease the technological challenges in the e-learning service. © 2019 IEEE.Item Mobile health system framework in India(Association for Computing Machinery, 2019) Pai, R.R.; Alathur, S.The healthcare system in India has been progressive with the specific health policies evolved over a period of time. Currently, it is in a phase of incorporating mobile technology into healthcare service delivery (i.e., mobile health) to make it a patient-centric model for managing acute, chronic, and preventive health conditions. This provides authentic interactions between the patient/user and the healthcare professionals for seeking health communication and information during emergencies and disaster conditions. However, there exists a great challenge in integrating mobile health solutions within the existing system and acceptance among the individuals, as the patient data is primarily collected through sensors and while the interventions are connected electronically. With this aim, the present research by using qualitative interviews (among residents and technology entrepreneurs) attempts to propose a provenance framework for the mobile health system in India. It also highlights its strengths and weakness and delineates components identified from qualitative interviews for describing the proposed provenance framework. © 2019 Association for Computing Machinery.Item Effect of pH on the geotechnical properties of laterite(2006) Sunil, B.M.; Nayak, S.; Shrihari, S.Environmental Geotechnology has emerged as an interdisciplinary science, aiming and forecasting, analyzing and solving the geotechnical problems involving the influence of environmental factors. Lateritic soil of west coast region of India was studied to investigate the effect of soaking on the engineering properties and chemical characteristics of soil, soaked in different pH solutions (pH = 5.0, pH = 7.0, pH = 8.0). 12 N hydrochloric acid and 15 M ammonia solution were used to monitor the pH of the solution for about ninety days. Results showed that the pH of the solution has strong influence on the chemical characteristics of lateritic soil. The engineering properties of soil are altered when compared with the initial characteristics of the soil. The reason for this observed behavior of the soil is addressed in this paper. © 2006 Elsevier B.V. All rights reserved.Item Performance evaluation of reference evapotranspiration equations across a range of Indian climates(2006) Nandagiri, L.; Kovoor, G.M.Reference crop evapotranspiration (ET0) is a key variable in procedures established for estimation of evapotranspiration rates of agricultural crops. In recent years, there is growing evidence to show that the more physically based FAO-56 Penman-Monteith (PM) combination method yields consistently more accurate ET0 estimates across a wide range of climates and is being proposed as the sole method for ET0 computations. However, other methods continue to remain popular among Indian practitioners either because of traditional usage or because of their simpler input data requirements. In this study, we evaluated the performances of several ET0 methods in the major climate regimes of India with a view to quantify differences in ET0 estimates as influenced by climatic conditions and also to identify methods that yield results closest to the FAO-56 PM method. Performances of seven ET0 methods, representing temperature-based, radiation-based, pan evaporation-based, and combination-type equations, were compared with the FAO-56 PM method using historical climate data from four stations located one each in arid (Jodhpur), semiarid (Hyderabad), subhumid (Bangalore), and humid (Pattambi) climates of India. For each location, ET0 estimates by all the methods for assumed hypothetical grass reference crop were statistically compared using daily climate records extending over periods of 3-4 years. Comparisons were performed for daily and monthly computational time steps. Overall results while providing information on variations in FAO-56 PM ET0 values across climates also indicated climate-specific differences in ET0 estimates obtained by the various methods. Among the ET0 methods evaluated, the FAO-56 Hargreaves (temperature-based) method yielded ET0 estimates closest to the FAO-56 PM method both for daily and monthly time steps, in all climates except the humid one where the Turc (radiation-based) was best. Considering daily comparisons, the associated minimum standard errors of estimate (SEE) were 1.35, 0.78, 0.67, and 0.31 mm/day, for the arid, semiarid, subhumid, and humid locations, respectively. For monthly comparisons, minimum SEE values were smaller at 0.95, 0.59, 0.38, and 0.20 mm/day for arid, semiarid, subhumid, and humid locations, respectively. These results indicate that the choice of an alternative simpler equation in a particular climate on the basis of SEE is dictated by the time step adopted and also it appears that the simpler equations yield much smaller errors when monthly computations are made. In order to provide simple ET0 estimation tools for practitioners, linear regression equations for preferred FAO-56 PM ET0 estimates in terms of ET0 estimates by the simpler methods were developed and validated for each climate. A novel attempt was made to investigate the reasons for the climate-dependent success of the simpler alternative ET0 equations using multivariate factor analysis techniques. For each climate, datasets comprising FAO-56 PM ET0 estimates and the climatic variables were subject to factor analysis and the resulting rotated factor loadings were used to interpret the relative importance of climatic variables in explaining the observed variabilities in ET0 estimates. Results of factor analysis more or less conformed the results of the statistical comparisons and provided a statistical justification for the ranking of alternative methods based on performance indices. Factor analysis also indicated that windspeed appears to be an important variable in the arid climate, whereas sunshine hours appear to be more dominant in subhumid and humid climates. Temperature related variables appear to be the most crucial inputs required to obtain ET0 estimates comparable to those from the FAO-56 PM method across all the climates considered. © 2006 ASCE.Item Industrial estate planning for Mangalore Taluk in Karnataka, using remote sensing and GIS(2006) Navalgund, L.; Shreedhara, V.; Srinikethan, G.The present work presents a technique to prepare zoning atlas to classify the environment and risks involved in siting an industry. Based on risks involved in a classified zone, the best-suited industries are recommended. Mangalore city has been taken as the study area has for the present work. Sensitivity of study area has been checked in terms of air pollution, surface water pollution and groundwater pollution. The study relies upon the database procured for this purpose from Central Pollution Control Board (CPCB) and Karnataka State Remote Sensing Technology, Bang lore. The database mainly comprises of topographic maps, thematic maps and groundwater information. Buffering and over-laying of the thematic maps have been carried out as per the guidelines of CPCB. © Enviromedia Printed in India. All rights reserved.Item Natural and anthropogenic factors controlling the dissolved organic carbon concentrations and fluxes in a large tropical river, India(2006) Balakrishna, K.; Kumar, I.A.; Srinikethan, G.; Mugeraya, G.Carbon studies in tropical rivers have gained significance since it was realized that a significant chunk of anthropogenic CO2 emitted into the atmosphere returns to the biosphere, that is eventually transported by the river and locked up in coastal sediments for a few thousand years. Carbon studies are also significant because dissolved organic carbon (DOC) is known to complex the toxic trace metals in the river and carry them in the dissolved form. For the first time, this work has made an attempt to study the variations in DOC concentrations in space and time for a period of 19 months, and estimate their fluxes in the largest peninsular Indian river, the Godavari at Rajahmundry. Anthropogenic influence on DOC concentrations possibly from the number of bathing ghats along the banks and domestic sewage discharge into the river are evident during the pre-monsoon of 2004 and 2005. The rise in DOC concentrations at the onset of monsoon could be due to the contributions from flood plains and soils from the river catchment. Spatial variations highlighted that the DOC concentrations in the river are affected more by the anthropogenic discharges in the downstream than in the upstream. The discharge weighted DOC concentrations in the Godavari river is 3-12 times lower than Ganga-Brahmaputra, Indus and major Chinese rivers. The total carbon fluxes from the Godavari into the Bay of Bengal is insignificant (0.5%) compared to the total carbon discharges by major rivers of the world into oceans. © Springer Science+Business Media, Inc. 2006.