Journal Articles

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A comparative study of subject headings in university libraries in karnataka
(Journal of Library Development, 2018-08) Harinarayana, N. S.; Chandrappa
Subject cataloguing is considered more intellectually intriguing than the descriptive cataloguing. Quality of subject catalogues have been the area of interest for researchers. The present study attempted to analyse the subject catalogue records from four university libraries in Karnataka. The result showed that the subject access to the holdings of the university libraries need to be improved. Subject cataloguers have to pay immediate attention in improving the subject access.
A Coordinated Control Strategy for a Diesel-Electric Tugboat System for Improved Fuel Economy
(IEEE, 2020-07-21) Upadhyayula, Ramesh Srinivas
Recent growth in seaborne trade has increased the tugboat operation cycle to maneuver incoming marine vessels at port. To meet the tugboat load demand for maneuvering, multiple power sources are being employed on-board. This necessitates a coordinated control strategy for the effective operation of these multiple power sources. To design an effective coordinated control strategy, this article initially estimates multiple power sources capacities (doubly fed induction machine (DFIM) and battery storage system) for a diesel-electric tugboat system based on a real-time tugboat operation cycle obtained from Visakhapatnam port, India. With respect to these multiple power sources, a coordinated control strategy for a better fuel efficiency is proposed based on a state machine control algorithm. The proposed control strategy operates a variable speed diesel-electric generator (diesel engine coupled DFIM) at a minimum specific fuel consumption value and battery based on its state of charge. To show the efficacy of the proposed variable speed diesel-electric system, fuel consumption is computed, which resulted in 26.42% of saving in comparison with a traditionally used diesel-mechanical tugboat. To evaluate the real-time system (2 MW DFIM + 150 kWh battery), MATLAB/Simulink tool is used and an experimental demonstration is performed on a laboratory prototype.
A coordinated control strategy for a diesel-electric tugboat system for improved fuel economy /
(IEEE, 2020-07-21) Upadhyayula, Ramesh Srinivas
Recent growth in seaborne trade has increased the tugboat operation cycle to maneuver incoming marine vessels at port. To meet the tugboat load demand for maneuvering, multiple power sources are being employed on-board. This necessitates a coordinated control strategy for the effective operation of these multiple power sources. To design an effective coordinated control strategy, this article initially estimates multiple power sources capacities (doubly fed induction machine (DFIM) and battery storage system) for a diesel-electric tugboat system based on a real-time tugboat operation cycle obtained from Visakhapatnam port, India. With respect to these multiple power sources, a coordinated control strategy for a better fuel efficiency is proposed based on a state machine control algorithm. The proposed control strategy operates a variable speed diesel-electric generator (diesel engine coupled DFIM) at a minimum specific fuel consumption value and battery based on its state of charge. To show the efficacy of the proposed variable speed diesel-electric system, fuel consumption is computed, which resulted in 26.42% of saving in comparison with a traditionally used diesel-mechanical tugboat. To evaluate the real-time system (2 MW DFIM + 150 kWh battery), MATLAB/Simulink tool is used and an experimental demonstration is performed on a laboratory prototype.
A description of tidal propagation in Hooghly estuary using numerical and analytical solutions
(Ocean Engineering, 2018) Jena, B. K.; Sivakholundu, K. M.; Rajkumar, J.
A tidal propagation characteristic of Hooghly estuary is presented using numerical (ADCIRC) and analytical models (Friedrichs and Aubrey, 1994) along with observations. The analytical model is based on Friedrichs and Aubrey (1994) that simplifies the governing hydrodynamic equations greatly by retaining only those terms that are significant without losing the overall understanding of the propagation process. The analytical model is compared with corresponding 2-D depth averaged numerical (ADCIRC) model that retains all non-linear terms. The assumptions for simplification are found to be reasonable in the light of close agreement among analytical, numerical models and observations. A plan-form geometrical characteristic as well as hydrodynamic variable of the Hooghly has been compared with that of Delaware estuary for corroborating similar tidal propagation process. The Hooghly estuary has flood dominant asymmetric tidal propagation and a positive amplitude growth factor (μ). The observed tidal celerity (phase speed) on an average is slightly more than frictionless celerity. Using the conventions of Toffolon et al. (2006), Hooghly can be classified into ‘strongly convergent – strongly dissipative’ estuary. From the results it can be construed that the estuary is yet to stabilise and reach its equilibrium morphology. It can be close to its equilibrium as very little amplification (0.1 m) is noticed in the predominant semi-diurnal constituent M2 over 78 km (barely 7%) in the estuary. The parameters of width variation (γ) and the ratio between friction and inertia (χ) have been used to define the marginal condition for amplification. The relative position of Hooghly in terms of marginal condition is consistent with similar set of estuaries elsewhere that have been grouped using the above parameters.
A description of tidal propagation in Hooghly estuary using numerical and analytical solutions /
(Elsevier, 2018-09-18) Sivakholundu, K.M.
A tidal propagation characteristic of Hooghly estuary is presented using numerical (ADCIRC) and analytical models (Friedrichs and Aubrey, 1994) along with observations. The analytical model is based on Friedrichs and Aubrey (1994) that simplifies the governing hydrodynamic equations greatly by retaining only those terms that are significant without losing the overall understanding of the propagation process. The analytical model is compared with corresponding 2-D depth averaged numerical (ADCIRC) model that retains all non-linear terms. The assumptions for simplification are found to be reasonable in the light of close agreement among analytical, numerical models and observations. A plan-form geometrical characteristic as well as hydrodynamic variable of the Hooghly has been compared with that of Delaware estuary for corroborating similar tidal propagation process. The Hooghly estuary has flood dominant asymmetric tidal propagation and a positive amplitude growth factor (μ). The observed tidal celerity (phase speed) on an average is slightly more than frictionless celerity. Using the conventions of Toffolon et al. (2006), Hooghly can be classified into ‘strongly convergent – strongly dissipative’ estuary. From the results it can be construed that the estuary is yet to stabilise and reach its equilibrium morphology. It can be close to its equilibrium as very little amplification (0.1 m) is noticed in the predominant semi-diurnal constituent M2 over 78 km (barely 7%) in the estuary. The parameters of width variation (γ) and the ratio between friction and inertia (χ) have been used to define the marginal condition for amplification. The relative position of Hooghly in terms of marginal condition is consistent with similar set of estuaries elsewhere that have been grouped using the above parameters.
A Diagnostic Approach for Cost Minimization and Profit Maximization between User Agencies and The Service Providers in Indian Ports /
(Zenodo, 2018-07-05) Swaminathan, B.
The objective of the paper is how to reduce the cost of port services to the users of the port without affecting its profitability. They range from service quality and value for money to investment returns and economic efficiency. The rationale behind the port costing is that it enables port management to control costs and operations and allocate resources efficiently. In spite of this, one of the major setbacks that Industry has been facing is the cost of doing business which is highest compared with the rest of the world. Cost minimization is the task to reduce costs by consuming resources more efficiently. Ports ultimately want to reduce costs and increase production. The question they must answer is, how to accomplish this task?
A fast and effective method for assessing insulation condition based on time domain spectroscopy data /
(IEEE, 2022-01-21) Mishra, D.
A novel methodology is suggested to predict the condition of Oil-paper Insulation (OPI), popularly used in power transformers. The proposed method is based on transient measurement of polarization current data from laboratory samples. Initially, complete polarization current profile is used to formulate an insulation model and then find the rise time of the system. After that, a relation is provided between rise time and measured performance parameters like moisture content(%pm). Further, another relation is suggested between rise time and the initial decay rate of recorded data. Hence, just by knowing the value of the initial decay rate, the value of crucial parameters like %pm can be evaluated using the proposed relationship.
A Marketing Strategy for Small and Medium Enterprises
(Elsevier, 2013-01-01) Yadav, Ramanand
Small and medium enterprises (SMEs), in Indian context, constitutes of a larger share of GDP, GNP, employment potential and occupation of masses. These enterprises have left remarkable spot on the every field of Indian economy, but, in overall, they are far behind their larger counterparts in other parts of the economy. With representing largest share of industrial activities, SMEs are heterogeneous in nature. The paper highlights that marketing strategy for SMEs is necessary, which can be developed by developing a suitable business environment. The author also elaborated that business environment in Indian SMEs is not conducive and needed training, proactiveness, favourable tax structure, reformed labour laws and sufficiency of infrastructure facilities. In addition to this, it is also emphasized that these enterprises can enhance their business environment by adopting certain financial and non-financial measures. This paper is also structured with an objective to provide a framework to help SMEs to design suitable strategies to face effective and enhancing competitiveness.
A Mathematical Model for Scheduling a Batch Processing Machine with Multiple Incompatible Job Families, Non-identical Job dimensions, Non-identical Job sizes, Non-agreeable release times and due dates /
(IOP Publishing, 2013-06-06) Ramasubramaniam, M
The paper addresses the problem scheduling a batch processing machine with multiple incompatible job families, non-identical job dimensions, non-identical job sizes and non-agreeable release dates to minimize makespan. The research problem is solved by proposing a mixed integer programming model that appropriately takes into account the parameters considered in the problem. The proposed is validated using a numerical example. The experiment conducted show that the model can pose significant difficulties in solving the large scale instances. The paper concludes by giving the scope for future work and some alternative approaches one can use for solving these class of problems.
A mathematical model of marine diesel engine speed control system
(Journal of The Institution of Engineers (India): Series C, 2018-02) Sinha, Rajendra Prasad.; Balaji, Rajoo.
Diesel engine is inherently an unstable machine and requires a reliable control system to regulate its speed for safe and efficient operation. Also, the diesel engine may operate at fixed or variable speeds depending upon user’s needs and accordingly the speed control system should have essential features to fulfil these requirements. This paper proposes a mathematical model of a marine diesel engine speed control system with droop governing function. The mathematical model includes static and dynamic characteristics of the control loop components. Model of static characteristic of the rotating fly weights speed sensing element provides an insight into the speed droop features of the speed controller. Because of big size and large time delay, the turbo charged diesel engine is represented as a first order system or sometimes even simplified to a pure integrator with constant gain which is considered acceptable in control literature. The proposed model is mathematically less complex and quick to use for preliminary analysis of the diesel engine speed controller performance.
A new archaeological find in the Gulf of Cambay, Gujarat
(Journal of the Geological Society of India, 2002) Kathiroli, S.; Badrinarayanan, S.; Venkata Rao, D.; Rajaguru, S.; Sivakholundu, K. M.; Sasisekaran, B.
Detailed underwater surveys carried out in the Gulf of Cambay, about 20 km west of Hazira, deploying side scan sonar and sub bottom profiler brought to light, the presence of a submerged palaeochannel traceable to a length of 9 km. Associated with this on either side are basement like features found in a grid pattern at water depths of 20-40 m. Sub-surface sampling carried out with dredge and grab sampler revealed stone artefacts, potsherds, hearth pieces, animal bones and human teeth embedded in fluvial sands and silts. In the upper part of the deposit, a carbonised wooden log was found and dated to around 9500 years BP by 14C method. Marine magnetic survey carried-out does not indicate the presence of any major metallic debrislobjects. This appears to be one of the early records of prehistoric human activity of early Holocene age in the marine environment of India.
A nonlinear regression-based approach to assess transformer insulation condition using dielectric response recorded for short duration /
(IEEE, 2023-01-01) Mishra, Deepak
Analysis of polarization current data is generally done to assess power transformer insulation condition. Due to considerable measurement time and low magnitude, noise and other environmental factors often affect the recorded dielectric response data. The influence of these factors cannot be avoided during field measurement. Once the recorded data are affected by external factors, it becomes difficult to analyze the data. Available literature has reported some techniques to reduce the testing time. However, these reported methods are ineffective in addressing the practical issues experienced during field measurement. This present article proposes a nonlinear regression-based approach to reduce insulation response measurement time significantly. Data collected from various in situ transformers have been analyzed to test the effectiveness of the proposed method.
A novel and fast approach for sensing activation energy for reliable health assessment of power transformer
(IEEE, 2022-09-13) Mishra, Deepak; Baral, Arijit; Chakravorti, Sivaji
Activation energy represents the average rate of interaction between aging by-products and cellulose. Activation energy is a crucial parameter that can be used to identify the remaining life of insulation in high voltage (HV) equipment. Existing noninvasive methods take a significantly longer time to sense activation energy for given insulation. This is primarily due to the volume of data required for such analysis, which generally takes significant time to measure. This work reports a noninvasive and effective approach to predict activation energy of oil–paper insulation using a dielectric response that is recorded for a very short span of time. The proposed method requires polarization current data sensed for a few seconds (15–20 s) to operate. The initial decay rate (DR) of the sensed data is found to be sensitive to the activation energy. This feature of the initial DR is utilized to sense the value of activation energy within a short duration. The proposed technique utilizes the current sensor (present within an electrometer) more efficiently. This facilitates the measurement of a highly accurate polarization profile and ensures reliable activation energy estimation. The proposed methodology has been successfully applied to data collected from a few real-life transformers. Reported results show that the suggested method provides satisfactory results with good accuracy.
A novel and fast approach for sensing activation energy for reliable health assessment of power transformer /
(IEEE, 2022-09-13) Mishra, Deepak
Activation energy represents the average rate of interaction between aging by-products and cellulose. Activation energy is a crucial parameter that can be used to identify the remaining life of insulation in high voltage (HV) equipment. Existing noninvasive methods take a significantly longer time to sense activation energy for given insulation. This is primarily due to the volume of data required for such analysis, which generally takes significant time to measure. This work reports a noninvasive and effective approach to predict activation energy of oil–paper insulation using a dielectric response that is recorded for a very short span of time. The proposed method requires polarization current data sensed for a few seconds (15–20 s) to operate. The initial decay rate (DR) of the sensed data is found to be sensitive to the activation energy. This feature of the initial DR is utilized to sense the value of activation energy within a short duration. The proposed technique utilizes the current sensor (present within an electrometer) more efficiently. This facilitates the measurement of a highly accurate polarization profile and ensures reliable activation energy estimation. The proposed methodology has been successfully applied to data collected from a few real-life transformers. Reported results show that the suggested method provides satisfactory results with good accuracy.
A novel approach towards gas turbine emission reduction by using neural networks /
(IEEE, 2023-11-15) Mitra, Kalyan
Optimizations of controlling parameters are the key factors to achieve effectual output and emission reduction from machinery running. This study relates prediction technology for gas turbine's (GT's) running optimization and emission reduction. The tool can identify upcoming disputes and alter the engine control setting to achieve highly efficient running operations. This research objects to get a machine learning approach to predict GT performance on emissions. The forecasting capabilities of this system are based on real-time data collected from a GT plant. A neural network is employed to analyze and predict the emissions of exhaust pollutants, primarily carbon monoxide and nitrogen oxides. The model performance is studied by considering the values of MSE, MAE, and residuals. The model's accuracy and precision are revealed by its low MSE (0.0035) and MAE (0.043). This approach is a cost-effective way to gage emissions accurately and can be used to confirm compliance with environmental regulations. It is also a helpful tool for monitoring the health of the turbine and identifying any potential issues with its operation.
A novel method to predict severity of thermal aging and degree of polymerization for reliable diagnosis of dry-type insulation
(IEEE, 2022-04) Mishra, Shalini; Baral, Arijit; Mishra, Deepak; Chakravorti, Sivaji
The effect of thermal aging on Nomex-paper-based vacuum pressure impregnation (VPI) insulation is reported in this article. The frequency-dependent dielectric loss of Nomex-paper-based VPI dry insulation is affected after significant thermal aging. This variation in dielectric loss of the insulation maintains a good correlation with the duration of thermal aging. A new parameter sensitive to the severity of thermal aging is also introduced. To identify the parameter, the excitation voltage waveform and the corresponding insulation response at a given frequency are required. Determining the parameter does not require denoising of recorded waveforms, reducing the overall computational burden. Based on the newly introduced parameter, a cost-effective method is proposed to predict the dielectric loss and degree of polymerization (DP) in a thermally aged VPI-type dry insulation. The proposed method employs the intermediate frequency range and hence does not require time-consuming low-frequency measurements.
A novel method to predict severity of thermal aging and degree of polymerization for reliable diagnosis of dry-type insulation /
(IEEE, 2022-01-01) Mishra, D.
The effect of thermal aging on Nomex-paper-based vacuum pressure impregnation (VPI) insulation is reported in this article. The frequency-dependent dielectric loss of Nomex-paper-based VPI dry insulation is affected after significant thermal aging. This variation in dielectric loss of the insulation maintains a good correlation with the duration of thermal aging. A new parameter sensitive to the severity of thermal aging is also introduced. To identify the parameter, the excitation voltage waveform and the corresponding insulation response at a given frequency are required. Determining the parameter does not require denoising of recorded waveforms, reducing the overall computational burden. Based on the newly introduced parameter, a cost-effective method is proposed to predict the dielectric loss and degree of polymerization (DP) in a thermally aged VPI-type dry insulation. The proposed method employs the intermediate frequency range and hence does not require time-consuming low-frequency measurements.
A program to compute the area of an irregular polygon on a spheroidal surface
(Computers and Geosciences, 1998) Sivakholundu, K. M.; Prabaharan, N.
A review of developments in ballast water management
(Environmental Reviews, 2014-03) Balaji, Rajoo.; Yaakob, Omar.; Koh, Kho King.
Transportation and translocation of non-native species by ships through ballast water is one of the current issues the shipping industry is trying to address. The Ballast Water Convention is nearing full ratification after which treatment of ballast water will become mandatory for most of the trading merchant vessel categories. Ballast water management systems employing various technologies are commercially available but at high costs. Economics apart, the efficiency of these technologies and realistic ways to ensure compliance with stricter requirements of some Administrations are issues that need to be focussed upon. With the report of the Environmental Protection Agency as an assessment reference, this paper reviews the treatment technologies. Juxtaposing reports of Lloyd’s Register on the status, a concise overview of the technologies has been projected. A sustainable ballast water management based on data and assessments is proposed. The management must be extended to both shore and on-board platforms for practices, treatment, sampling, testing, and recycling. An exemplar system harvesting shipboard waste heat is projected as a route for thermal treatment in combination with technologies showing potential for optimized ballast water management
A Roadmap for Implementing Total Quality Management Practices in Medium Enterprises /
(Elsevier, 2013-01-01) Yadav, Ramanand
This paper describes a seven point framework for effective total quality management (TQM) implementation in medium enterprises (MEs). This framework shows that top management commitment and involvement is indispensable in the formulation and implementation of various quality adoption steps. The significant steps of the framework include development of mission and vision statement, formulating implementation plan, ensuring employee involvement, establishing education and training programs and starting implementation phase. At the last, continuous improvement is required to maintain the implementation effort for excellence orientation. The primary objective of this study was to prescribe a roadmap for TQM practicing MEs to adopt excellent quality practices in a simplified way. The author also tried to highlight the theoretical background while emphasizing the importance of steps of quality improvement practices. The idea behind taking MEs for adopting TQM practices is that the characteristics of MEs are most suited for it. However, TQM is a modern quality management practice which can be applied successfully to any type of enterprises, irrespective of their affiliation.