Faculty Publications
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Item Model based hybrid approach to prevent SQL injection attacks in PHP(2011) Sadalkar, K.; Mohandas, R.; Pais, A.R.SQL Injection vulnerability is ranked 1st in the OWASP top 10 vulnerability list and has resulted in massive attacks on a number of websites in the past few years. Inspite of preventive measures like educating developers about safe coding practices, statistics shows that these vulnerabilities are still dominating the top. Various static and dynamic approaches have been proposed to mitigate this vulnerability. In this paper, we present a hybrid approach to prevent SQL injection attacks in PHP, a popular server side scripting language. This technique is more effective to prevent SQL injection attack in a dynamic web content environment without use of complex string analyzer logic. Initially, we construct a Query model for each hotspot by running the application in safe mode. In the production environment, dynamically generated queries are validated with it. The results and analysis shows the proposed approach is simple and effective to prevent common SQL injection vulnerabilities. © 2011 Springer-Verlag.Item Experimental investigation of RC frames using CFRP sheets(2013) Prashanth, M.H.; Babu Narayan, K.S.; Venkataramana, K.; Sajith, M.Reinforced Concrete frames are the main load resisting systems used in practice all over the world. These frames will be subjected to sway, due to lateral loading most of the times by either earthquake or wind. Ductility and energy dissipation capacity of the frame are the key parameters for better performance under the action of the sway loading. Retrofitting using the new generation material such as carbon fiber reinforced plastic sheets (CFRP) shows much enhancement in these properties of laterally loaded frames. Frames subjected to lateral loading introduce collapse mechanism due to the formation of the plastic hinges at critical hinge locations. An experimental investigation of partially and fully CFRP wrapped reinforced concrete (RC) frames when compared to conventional(bare) frame has been carried out, to bring out the importance of critical engineered locations to be wrapped. © 2013 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Managing seismic risk in ancient structures: Coupled variables under numerical and experimental approaches(2013) Pineda, P.; Venkat Reddy, D.Analysis and evaluation of seismic reliability of masonry cultural heritage buildings is a difficult task, owing to a great number of uncertainties. In thesefew lines, many questions are posed, trying to learn from the wisdom of ancient times and remembering the advantages of using multidisciplinary tools when the seismic safety is the main concern. © 2013 CAFET-INNOVA TECHNICAL SOCIETY.Item Studies on the dynamic characteristics of monolithic RC wall panels(2013) Amitha, S.B.; Chethan, K.; Bhavanishankar, S.; Annapurna, B.P.; Venkataramana, K.; Ramesh Babu, R.Monolithically built RC wall panels permits for the industrialized construction of a group of integrated buildings using mechanized, rationalized and mass-production procedure. This is a unique, fast and economical technique. Most of the national and international codes comprise of a brief design procedure of this type of construction. Lot of research is being carried out worldwide about the effect of dynamic loads on these structures. In this paper, FE analysis is done on a designed typical monolithic RC wall panel structure for all zones as per Indian code and the results are compared with different international codal provisions and the formulae presented by Saheb & Desayi and Doh & Fragomeni. This paper consists of background, design and construction of monolithic RC wall panel, FE analysis and comparison of results. © 2013 CAFET-INNOVA TECHNICAL SOCIETY.Item Performance of berthing structure under static and dynamic loading(CAFET INNOVA Technical Society cafetinnova@gmail.com 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2014) Yajnheswaran; Rao, S.In berthing structures, lateral forces are caused by impact of berthing ships, pull from mooring ropes and pressure of wind, current, wave and floating ice, seismic force, active earth pressure and differential water pressure, and vertical loads are due to self-weight of the structure and live load. In the analysis considered there is an expansion joint between berthing structure and diaphragm wall. The analysis is carried out using the finite element software PLAXIS 2D with absence of anchor and varying locations of anchor of diaphragm wall. In the case of static loading, the extreme displacement, and bending moment of the diaphragm wall were found to be about 0.07342m,24936.03knm/m respectively in absence of anchor. In the case of seismic loading of the structure, the maximum displacement and bending moment of the diaphragm wall were around0.0749m28263.68knm/m in absence of anchor condition. When anchor is provided the maximum displacement and bending moment were reduced to 0.00642m and 11830knm/m respectively. The variation of bending moment is 13.34% more in dynamic analysis than static analysis. The variation of displacement is 2%more in dynamic analysis than static analysis. © 2014 CAFET-INNOVA TECHNICAL SOCIETY.Item Dynamic performance evaluation of automated QFT robust controller for grid-tied fuel cell under uncertainty conditions(Elsevier Ltd, 2020) Gudimindla, H.; K, M.S.Power flow control and peak point tracking are significant in grid-tied renewable energy systems to improve power factor and efficient energy extraction. In this paper, the design of robust controllers for the power electronic converters of the grid-connected PEM fuel cell with thermal modeling is deliberated. Further, the transfer function model of the power electronic converters is derived by considering uncertainty in system parameters. A low complexity algorithm is used to design the converter parameters from the uncertainty range. The proposed robust automated power flow controller is designed to minimize the objective function using a genetic algorithm in the quantitative feedback theory framework. The robustness and disturbance rejection with enhanced transient response of the proposed controller is evaluated under heavy and light loading conditions, DC-link voltage and grid voltage distortion uncertainty conditions are investigated. Finally, comprehensive simulations are performed to validate the proposed controller performance with the existing controller under the above-mentioned uncertainty conditions. © 2020 Elsevier LtdItem Effective configuration of perforated baffle plate for efficient slosh damping in liquid retaining tanks under lateral excitation(Elsevier Ltd, 2022) Nimisha, P.; Jayalekshmi, B.R.; Venkataramana, K.Perforated baffle plates are used as an anti-slosh mechanism in various fields owing to the need for slosh suppression and weight reduction. However, there is an uncertainty in the selection of configuration of perforated baffle plate due to the several influencing parameters for slosh damping efficiency. Therefore, the present study focuses on the development of an efficient slosh damping configuration for the perforated baffle plate. For this, nonlinear dynamic analysis under seismic ground motions with different PGA/PGV ratios has been carried out in the time domain using the concepts of Computational Fluid Dynamics (CFD) in the numerical models of liquid tanks with perforated baffle plates of different configurations. The response of the system under impulsive and convective modes is analysed by observing the free surface elevation, hydrodynamic pressure, turbulence kinetic energy and turbulence eddy dissipation as the response parameters. The study developed an effective baffle configuration for efficient slosh damping, considering the various response parameters. © 2022 Elsevier LtdItem Ground motion duration predictive models applicable for the Himalayan region(Springer, 2023) Anbazhagan, P.; Motwani, K.Several empirical models for the prediction of ground motion duration were developed across the world, but no model has been generated for the Himalayan region in the past. In this study, an attempt is made to study the duration models developed for different regions and compare them with a reference model developed for the Himalayan region for a wide range of magnitudes. The comparison is performed using the log-likelihood method and aims to identify the best duration prediction models based on the developed by Bajaj and Anbazhagan (2019) for the study region. The data support index values along with the weights of the corresponding models across the different distances and magnitude ranges have also been estimated. The study found that the predictive duration relation given by Lee and Green (2014) for Western North America is suitable for M ≤ 5, while the model developed by Ghanat (2011) is suitable for M > 5 for the Himalayan region. The model developed by Afshari and Stewart (2016) is also very close to the reference model. It is always preferable to have a single duration predictive model for a wide range of magnitude and distance range; hence, there is a need to develop a region-specific duration predictive model for the Himalayan region. © 2023, Indian Academy of Sciences.Item Hydrodynamic analysis of an H-shaped pile-restrained floating breakwater combined with a pair of vertical barriers(Elsevier Ltd, 2024) Panda, A.; Karmakar, D.; Rao, M.The present study analyses the performance of a composite breakwater consisting of an H-shaped breakwater attached with vertical/inclined barriers held from both sides using the Multi-Domain Boundary Element Method (MDBEM). The study is performed to analyse the wave transformation characteristics (reflection and transmission), wave energy dissipation and horizontal wave forces due to the gravity wave-structure interaction. The hydrodynamic performance of the integrated breakwater is performed due to the effect of changing various structural properties such as porosity, width and depth of structural elements, relative spacing between breakwater and barrier, angle of incidence and the inclination of the barriers. The boundary conditions and the corresponding edge conditions are incorporated for each surface and interface and correlated with Green's function to solve the boundary value problem. The detailed study proposes the suitable dimensions of the structural elements of the breakwater for optimal performance. The application of inclined barriers over the vertical barrier in certain conditions for maximising wave reflection is presented and analysed to understand the effectiveness of the barrier inclination. The favourable barrier dimensions and the suitable relative spacing for deep water regions are discussed, and the effect of rigidity and porosity of the barriers are analysed to maximise breakwater performance in wave attenuation. On considering the suitable design parameters and structural stability, the composition of vertical/inclined barriers with an H-shaped pile-restrained floating breakwater serves as a protective component by encountering maximum wave force and dissipating considerable wave energy to provide an efficient solution in harbour protection. © 2024 Elsevier LtdItem Influence of Stiffness Ratio and Powder Factor on Burden Rock Movement in Blasting Operations: A Case Study on Limestone Mines(World Researchers Associations, 2025) Channabassamma, N.; Akhil, A.; Rama, S.V.In opencast mining, blasting is a critical operation that significantly impacts the efficiency and costeffectiveness of material removal. This study focuses on optimizing the use of explosive energy to move the burden, thereby reducing reliance on mechanical methods. Effective blast design involves strategically utilizing energy within a blast hole, considering factors such as explosive type, quantity, detonation timing and blast hole geometry. Given the rapid nature of blasting, high-speed video cameras are employed to capture the blast progression on a millisecond scale, providing essential data for analyzing blast dynamics. This research evaluates the influence of blast design parameters, specifically the stiffness ratio (the ratio of bench height to the burden) and powder factor (the amount of explosive per unit volume of rock), on the movement of burden rock in a limestone mine. By examining these parameters, the study aims to optimize blast designs to achieve improved fragmentation, reduced fly rock and minimized ground vibrations, ultimately enhancing the efficiency and cost effectiveness of mining operations. © 2025, World Researchers Associations. All rights reserved.