Faculty Publications
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Item Analysis of observed soil moisture patterns under different land covers in Western Ghats, India(2011) Venkatesh, B.; Lakshman, N.; Purandara, B.K.; Reddy, V.B.An understanding of the soil moisture variability is necessary to characterize the linkages between a region's hydrology, ecology and physiography. In the changing land use scenario of Western Ghats, India, where deforestation along with extensive afforestation with exotic species is being undertaken, there is an urgent need to evaluate the impacts of these changes on regional hydrology. The objectives of the present study were: (a) to understand spatio-temporal variability of soil water potential and soil moisture content under different land covers in the humid tropical Western Ghats region and (b) to evaluate differences if any in spatial and temporal patterns of soil moisture content as influenced by nature of land cover. To this end, experimental watersheds located in the Western Ghats of Uttara Kannada District, Karnataka State, India, were established for monitoring of soil moisture. These watersheds possessed homogenous land covers of acacia plantation, natural forest and degraded forest. In addition to the measurements of hydro-meteorological parameters, soil matric potential measurements were made at four locations in each watershed at 50 cm, 100 cm and 150 cm depths at weekly time intervals during the period October 2004-December 2008.Soil moisture contents derived from potential measurements collected were analyzed to characterize the spatial and temporal variations across the three land covers. The results of ANOVA (p<0.01, LSD) test indicated that there was no significant change in the mean soil moisture across land covers. However, significant differences in soil moisture with depth were observed under forested watershed, whereas no such changes with depth were noticed under acacia and degraded land covers. Also, relationships between soil moisture at different depths were evaluated using correlation analysis and multiple linear regression models for prediction of soil moisture from climatic variables and antecedent moisture condition were developed and tested. A regression model relating near-surface soil moisture (50 cm) with profile soil moisture content was developed which may prove useful when surface soil moisture contents derived from satellite remote sensing are available. Overall results of this study indicate that while the nature of land cover has an influence on the spatio-temporal variability of soil moisture, other variables related to topography may have a more dominant effect. © 2010 Elsevier B.V.Item Geomorphological behaviour of Sasihithlu, Mangalore coast, west coast of India(2011) Nagaraj, G.; Karjagi, A.; Kumar, M.; Dwarakish, G.S.Beach geomorphological studies have been carried out with help of conventional methods and remote sensing techniques. Conventional methods include beach profile surveys and beachwidth measurements whereas remote sensing techniques involved in utilization of satellite images, digitization and analyses. Beach profile surveys and beachwidth measurements are carried out at monthly intervals over a period of one year (September 2009 to September 2010) to understand dynamics of sediment along the coastal segment of 7km at Sasihithlu, north off Mangalore coastline. Six locations are selected based on their significant site characteristics along the coastal segment. It is observed erosion with steeper slopes during the monsoon and simultaneously deposition with flat and wider exposed slopes during the fair weather season. But the more drastic and dramatic changes are observed in the vicinity of Mulki-Pavanje rivermouth, since the rivers Mulky and Pavanje bring any kind of sediments irrespective of seasons. Because of this the profiles alter dramatically in the vicinity of rivermouth. It is estimated that the Sasihithlu beach has experienced a net loss of about 2515m 3/m, a net gain of about 3525m 3/m and hence a gain of about 1010m 3/m sediments in an annual cycle. Addition to conventional methods, remote sensing analysis is also carried out to detect the influence of rivers and their flow on rivermouth system in recent decades (1988-2009) with the help of satellite images and GIS tools. It is observed that the shifting tendency of rivermouth either south or north irrespective of seasons. However a detailed investigation on shoreline pattern showed a clear indication of shifting shoreline towards south. Therefore present study suggests to construct coastal protection structures on either side of the rivermouth, through that the damage to the property could be minimized. © 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Energy efficient routing protocols for wireless sensor networks: A survey(2011) Shivaprakasha, K.S.; Kulkarni, M.Wireless Sensor Networks (WSNs) have become one of the emerging trends of the modern communication systems. They find their applications in various fields like habitat monitoring, home automation, environment monitoring, battle field environment etc. WSNs are different from Mobile Adhoc Networks in the perspective of energy awareness, adaptive communication patterns and the routing algorithms. As the sensor devices are powered by batteries, which cannot be recharged often, the power awareness is one of the major requirements in WSNs. Many energy aware routing protocols have been proposed in the literature. In this survey, an attempt has been made to summarize the various energy aware routing protocols available in the literature and also a comparative analysis of these has been made considering various network parameters like the delay, routing overhead, QoS, type of routing protocol etc. © 2011 Praise Worthy Prize S.r.l. - All rights reserved.Item A review on machining of titanium based alloys using EDM and WEDM(Institute of Problems of Mechanical Engineering mpm@def.ipme.ru, 2014) Manjaiah, M.; Narendranath, S.; Basavarajappa, S.The aim of this review is to present the consolidated information about the contributions of various researchers on the application of EDM and WEDM on titanium materials and subsequently identify the research gaps. The literature survey has been carried out from three perspectives such as application of EDM and WEDM on titanium materials, utilization of tools and techniques for correlating experimental results and application of products produced by EDM and WEDM. Three main research areas has been identified. First, the application of EDM and WEDM on titanium materials mainly TiNi based alloys. Second, the utilization of advanced tools and techniques such as artificial neural network (ANN), advanced particle swarm optimization (PSO) and tabu enhanced genetic algorithm (GA). Third, the study and analysis of surface integrity in EDM and WEDM on titanium materials. In addition, the paper has also evolved the future research directions. The paper has been concluded by indicating the future research directions for the research gaps identified during this literature survey.Item En-Route Filtering Techniques in Wireless Sensor Networks: A Survey(Springer New York LLC barbara.b.bertram@gsk.com, 2017) Kumar, A.; Pais, A.R.Majority of wireless sensor networks (WSNs) are deployed in unattended environments and thus sensor nodes can be compromised easily. A compromised sensor node can be used to send fake sensing reports to the sink. If undetected these reports can raise false alarms. To deal with the problem of fake report generation, a number of en-route filtering schemes have been proposed. Each of these schemes uses different cryptographic methods to check the authenticity of reports while they are being forwarded hop by hop toward base station. However, majority of these techniques can handle only limited compromised nodes or they either need node localization or statically configured routes for sending reports. Furthermore, majority of en-route filtering techniques are vulnerable to various denial of service attacks. Our main aims in this survey are: (a) to describe the major en-route filtering techniques, (b) to analyze these techniques on various parameters including security and (c) to outline main unresolved research challenges in en-route filtering in WSNs. © 2017, Springer Science+Business Media New York.Item Performance analysis of vertically offset overlapped propulsion system based quadrotor in an aerial mapping mission(SAGE Publications Inc. claims@sagepub.com, 2018) Nandakumar, G.; Saphal, R.; Joishy, A.; Thondiyath, A.In this paper, the authors present the performance analysis of a Vertically Offset Overlapped Propulsion System (VOOPS)-based quadrotor in an aerial mapping mission. The dynamic model of the VOOPS quadrotor with the effect of overlapping propellers and the profile drag has been derived and simulated. A path-tracking mission is taken as an example for aerial survey. The controller used for this task is presented, followed by the response study of the attitude and the position controller with standard test inputs. A graphical interface has been built to select the area to be mapped by defining a polygon around it, and waypoints for lawn-mower type survey grid were generated based on the direction of wind. The path-tracking algorithm is presented along with course correction and simulations were performed with both conventional and VOOPS quadrotor. An experimental vehicle based on the proposed VOOPS concept has been built, tested on the same path, and the results are discussed. The results show that the VOOPS quadrotor is capable of performing the aerial mapping mission with quick response and good accuracy. © The Author(s) 2018.Item Knowledge management influence on safety management practices evidence from construction industry(IGI Global cust@igi-global.com, 2019) Deepak, M.D.; Mahesh, G.; Medi, N.K.Many studies have been conducted in relation with knowledge management (KM), indicating the benefit associated with KM; among which safety management (SM) improvement is one of them. So, the aim of this article is to assess the influence of KM on SM practices in construction industry. In this regard, various factors that affect KM and SM are identified through literature review. Then, a questionnaire survey was facilitated to collect data based on the identified factors. These factors are ranked using a relative importance index (RII) to ascertain the level of importance among its group. Further, correlation analysis and multiple linear regression analysis are carried out to test and measure the strength of the relationship between KM and SM factors. Results indicate that there exists a definite and significant relationship between the factors of KM and SM in construction industry. Overall, the results obtained from the study will assist practitioners and professionals to develop and upgrade KM and SM practices in construction industry. © 2019, IGI Global.Item Developing a knowledge-based safety culture instrument for construction industry: Reliability and validity assessment in Indian context(Emerald Group Holdings Ltd., 2019) Deepak, M.D.; Mahesh, G.Purpose: Harnessing the power of knowledge management is important for minimizing accidents occurring at construction projects. Yet, knowledge management is a neglected dimension when developing safety culture in the construction industry. Therefore, the purpose of this paper is to develop a knowledge-based safety culture questionnaire and examine its validity and reliability in the Indian context. Design/methodology/approach: A questionnaire survey was formulated after identifying 69 influencing factors from a thorough literature review. In total, 210 valid responses were obtained from key stakeholders operating in Indian construction industry. Reliability and validity of the measurement scale were examined by factor analysis and inter-item correlation test. Comparison of knowledge-based safety culture scores across several demographic profiles of the respondents was utilized for testing discriminant validity. Findings: Results suggest that the new instrument appears to be a reliable, valid and sensitive instrument that will contribute in examining the effect of key factors that influence the importance of the knowledge dimension toward developing safety culture in the construction industry. Originality/value: The measurement tool developed in this study focuses on considering the importance of knowledge management in enhancing safety culture of the construction industry. This instrument can be utilized to compare the level of safety culture among key stakeholders of construction projects. This paper can contribute to the promotion of safety theory in Indian construction industry and provide practical implications for construction enterprises when they engage in improving safety conditions in their organizations. © 2019, Emerald Publishing Limited.Item Dimensions for improvement of construction management practice in Ethiopian construction industry(Emerald Group Holdings Ltd., 2020) Mengistu, D.G.; Mahesh, G.Purpose: The state of the different practices in construction industry determines its performance level. Hence, improving performance of construction industry needs assessing state of the practices in the industry and devising improvement intervention. The purpose of this paper is to measure improvement requirement level of different construction management practice areas and to identify the underlying improvement dimensions in Ethiopian construction industry. Design/methodology/approach: Questionnaire survey was developed for data collection based on a thorough literature review which yielded 28 construction management practice areas. Purposive sampling method was used to select respondents for the survey. Mean score was used to identify the required improvement level, and one sample T-test was carried out to identify significance of improvement requirement. Factor analysis was conducted to identify the underlying dimensions of the construction management practice areas. Findings: Findings indicate 27 areas need significant improvement. This shows the low level of adoption of good construction management practices in Ethiopian construction industry. Factor analysis resulted in the areas being grouped to four broad improvement dimensions, namely, project management, organization management, knowledge and risk management and project development and contract management. Originality/value: The findings provide information for appropriate action by the stakeholders to raise standards of adopted construction management practices. It also show areas of construction management which require more focused research in the context of Ethiopian construction industry. Considering the similarity of nature of construction industry problems in developing countries, the findings can be extended to similar countries. © 2019, Emerald Publishing Limited.Item Identifying the performance areas affecting the project performance for Indian construction projects(Emerald Group Holdings Ltd., 2021) Ingle, P.V.; Mahesh, G.; Deepak, D.Purpose: The construction industry is facing challenges because of performance shortfalls. Construction projects are highly complex, distinctive, fragmented and do not have well-established performance assessment models to evaluate their project success. The purpose of this paper is to assess the direction through determination of performance areas that would affect project performance in Indian construction projects. Design/methodology/approach: A survey instrument was developed to gather data on the perception of industry professionals on these identified areas. Purposive sampling method was used to select respondents for the survey. These performance areas are ranked using relative importance index to ascertain a level of importance among the group. Factor analysis (FA) was conducted to identify the significant performance areas project performance. Further to identify the most influence performance areas on Indian construction projects, multiple regression analysis was carried out. Findings: Findings indicated 28 significant performance areas. This shows the low level of adoption of good construction management practices in Indian construction projects. FA resulted in the areas being grouped to nine broad significant performance areas with 59.49% of the total variance, namely, quality, schedule, environment and stakeholder satisfactions, cost, productivity, safety, communication management, customer relations and finance. Multiple regression analysis revealed two pivotal factors “customer relations” and “schedule” that significantly influence project performance in Indian construction industry. Originality/value: The outcome of the study will guide project stakeholders, who desire to improve project performance on construction projects, to prioritize their efforts. It also highlights performance areas of project management which required more focussed research in the context of Indian construction projects. The findings can be extended to the developing countries. © 2020, Emerald Publishing Limited.