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Showing papers in "Sadhana-academy Proceedings in Engineering Sciences in 2016"


Journal ArticleDOI
TL;DR: The implementation of an inquisitive chatbot, which finds the missing data in query and probes the questions to users to collect data that are required to answer the query is reported.
Abstract: Chatbot is a piece of software that responds to natural language input and attempts to hold a conversation in a way that imitates a real person. Some chatbots are used for entertainment purposes, while others for business and commercial purposes. Chatbots are getting a lot of attention from business community right now as they can save costs in customer service centers and can handle multiple clients at a time. Successful implementation of a chatbot calls for correct analysis of user’s query by the bot and the formation of the correct response that should be given to the user. In many scenarios the information available from the user’s query is inadequate to provide the answer. In such contexts, the chatbot needs to be inquisitive so that it will be more interactive and can mimic a more natural human interaction. This paper reports the implementation of an inquisitive chatbot, which finds the missing data in query and probes the questions to users to collect data that are required to answer the query. Through this implementation, the level of interactivity between the user and the chatbot is improved.

53 citations


Journal ArticleDOI
TL;DR: A functional unobtrusive Indian sign language recognition system was implemented and tested on real world data and proposes a method for a novel, low-cost and easy-to-use application, for Indian Sign Language recognition, using the Microsoft Kinect camera.
Abstract: People with speech disabilities communicate in sign language and therefore have trouble in mingling with the able-bodied. There is a need for an interpretation system which could act as a bridge between them and those who do not know their sign language. A functional unobtrusive Indian sign language recognition system was implemented and tested on real world data. A vocabulary of 140 symbols was collected using 18 subjects, totalling 5041 images. The vocabulary consisted mostly of two-handed signs which were drawn from a wide repertoire of words of technical and daily-use origins. The system was implemented using Microsoft Kinect which enables surrounding light conditions and object colour to have negligible effect on the efficiency of the system. The system proposes a method for a novel, low-cost and easy-to-use application, for Indian Sign Language recognition, using the Microsoft Kinect camera. In the fingerspelling category of our dataset, we achieved above 90% recognition rates for 13 signs and 100% recognition for 3 signs with overall 16 distinct alphabets (A, B, D, E, F, G, H, K, P, R, T, U, W, X, Y, Z) recognised with an average accuracy rate of 90.68%.

49 citations


Journal ArticleDOI
TL;DR: It is demonstrated that study of interval-valued trapezoidal fuzzy numbers transportation problem gives rise to the same expected results as those obtained for TP with trapezoid fuzzy numbers.
Abstract: Transportation problem (TP) is an important network structured linear programming problem that arises in several contexts and has deservedly received a great deal of attention in the literature. The central concept in this problem is to find the least total transportation cost of a commodity in order to satisfy demands at destinations using available supplies at origins in a crisp environment. In real life situations, the decision maker may not be sure about the precise values of the coefficients belonging to the transportation problem. The aim of this paper is to introduce a formulation of TP involving interval-valued trapezoidal fuzzy numbers for the transportation costs and values of supplies and demands. We propose a fuzzy linear programming approach for solving interval-valued trapezoidal fuzzy numbers transportation problem based on comparison of interval-valued fuzzy numbers by the help of signed distance ranking. To illustrate the proposed approach an application example is solved. It is demonstrated that study of interval-valued trapezoidal fuzzy numbers transportation problem gives rise to the same expected results as those obtained for TP with trapezoidal fuzzy numbers.

40 citations


Journal ArticleDOI
Jingwu Bu1, Z Tian1
TL;DR: In this article, the pore structure features such as porosity, pore size distribution are extracted using mercury intrusion porosimetry technique and a statistical model is developed to relate the compressive strength to relevant pore structures features.
Abstract: Properties of concrete are strongly dependent on its pore structure features, porosity being an important one among them. This study deals with developing an understanding of the pore structure-compressive strength relationship in concrete. Several concrete mixtures with different pore structures are proportioned and subjected to static compressive tests. The pore structure features such as porosity, pore size distribution are extracted using mercury intrusion porosimetry technique. A statistical model is developed to relate the compressive strength to relevant pore structure features.

37 citations


Journal ArticleDOI
TL;DR: In this article, a control scheme for single phase grid connected photovoltaic (PV) system operating under both grid connected and isolated grid mode is presented, which includes voltage and current control of grid-tie PV inverter.
Abstract: This paper presents a control scheme for single phase grid connected photovoltaic (PV) system operating under both grid connected and isolated grid mode. The control techniques include voltage and current control of grid-tie PV inverter. During grid connected mode, grid controls the amplitude and frequency of the PV inverter output voltage, and the inverter operates in a current controlled mode. The current controller for grid connected mode fulfills two requirements – namely, (i) during light load condition the excess energy generated from the PV inverter is fed to the grid and (ii) during an overload condition or in case of unfavorable atmospheric conditions the load demand is met by both PV inverter and the grid. In order to synchronize the PV inverter with the grid a dual transport delay based phase locked loop (PLL) is used. On the other hand, during isolated grid operation the PV inverter operates in voltage-controlled mode to maintain a constant amplitude and frequency of the voltage across the load. For the optimum use of the PV module, a modified P&O based maximum power point tracking (MPPT) controller is used which enables the maximum power extraction under varying irradiation and temperature conditions. The validity of the proposed system is verified through simulation as well as hardware implementation.

33 citations


Journal ArticleDOI
TL;DR: A novel computer aided technique to classify abnormalities in mammograms using fusion of local and global features that has improved classification accuracy from 88.75% to 93.17%.
Abstract: Mammography is the most widely used tool for the early detection of breast cancer. Computer-based algorithms can be developed to improve diagnostic information in mammograms and assist the radiologist to improve diagnostic accuracy. In this paper, we propose a novel computer aided technique to classify abnormalities in mammograms using fusion of local and global features. The objective of this work is to test the effectiveness of combined use of local and global features in detecting abnormalities in mammograms. Local features used in the system are Chebyshev moments and Haralick’s gray level co-occurrence matrix based texture features. Global features used are Laws texture energy measures, Gabor based texture energy measures and fractal dimension. All types of abnormalities namely clusters of microcalcifications, circumscribed masses, spiculated masses, architectural distortions and ill-defined masses are considered. A support vector machine classifier is designed to classify the samples into abnormal and normal classes. It is observed that combined use of local and global features has improved classification accuracy from 88.75% to 93.17%.

31 citations


Journal ArticleDOI
TL;DR: A short questionnaire was conducted with 15 prominent factors responsible for cost overrun and forwarded to 190 constructional professionals across India, total 85 responses were received and it was analyzed using various statistical tools such as analysis of variance (ANOVA) and factor analysis tool using SPSS as discussed by the authors.
Abstract: Delay and cost overrun are common phenomena in projects worldwide. However, these are especially severe in developing countries. In India as per MOSPI report, 235 projects out of 410 were severely affected cost overrun due to certain factors. A short questionnaire was conducted with 15 prominent factors responsible for cost overrun and forwarded to 190 constructional professionals across India. Total 85 responses were received and it was analyzed using various statistical tools such as analysis of variance (ANOVA) and factor analysis tool using SPSS. In this study, top three factors affecting cost overruns were identified such as price escalation of raw material, delay in planned activity and lack of co-ordination between construction parties which could be significantly responsible for cost overnun of construction project in India. Factor analysis method was also carried out to group the factors into three components of overall questionnaire. These components, such as client control component, project management component, and contractor control component, would be useful to the various parties involved in the construction activities. This paper also provides suggestive frameworks which have been framed after discussing with large number of construction professionals or expert.

31 citations


Journal ArticleDOI
TL;DR: Suitability of the proposed RGB YCbCr Processing method is validated by real-time implementation during the testing of the Autonomous Underwater Vehicle (AUV-150) developed indigenously by CSIR-CMERI.
Abstract: An RGB YCbCr Processing method (RYPro) is proposed for underwater images commonly suffering from low contrast and poor color quality. The degradation in image quality may be attributed to absorption and backscattering of light by suspended underwater particles. Moreover, as the depth increases, different colors are absorbed by the surrounding medium depending on the wavelengths. In particular, blue/green color is dominant in the underwater ambience which is known as color cast. For further processing of the image, enhancement remains an essential preprocessing operation. Color equalization is a widely adopted approach for underwater image enhancement. Traditional methods normally involve blind color equalization for enhancing the image under test. In the present work, processing sequence of the proposed method includes noise removal using linear and non-linear filters followed by adaptive contrast correction in the RGB and YCbCr color planes. Performance of the proposed method is evaluated and compared with three golden methods, namely, Gray World (GW), White Patch (WP), Adobe Photoshop Equalization (APE) and a recently developed method entitled “Unsupervised Color Correction Method (UCM)”. In view of its simplicity and computational ease, the proposed method is recommended for real-time applications. Suitability of the proposed method is validated by real-time implementation during the testing of the Autonomous Underwater Vehicle (AUV-150) developed indigenously by CSIR-CMERI.

31 citations


Journal ArticleDOI
TL;DR: In this article, the authors presented a new adaptive scheme for energy management in an independent microgrid, which includes renewable sources as primary source and storage system as secondary source, and a wind generator and solar PV array system together act as the primary source, which supplies power to the local load most of the time.
Abstract: This work presents a new adaptive scheme for energy management in an independent microgrid. The proposed energy management system has been developed to manage the utilization of power among the hybrid resources and energy storage system in order to supply the load requirement based on multi-agent system (MAS) concept and predicted renewable powers and load powers. Auto regressive moving average models have been developed for predicting the wind speed, atmospheric temperature, irradiation, and connected loads. The structure proposed in this paper includes renewable sources as primary source and storage system as secondary source. A wind generator and solar PV array system together acts as primary source, which supplies power to the local load most of the time in this energy management strategy. When they fail to meet the load demand, the secondary source present in the system will assist the primary source and help to attain the goal of satisfying load demand without interruption. If the primary source and secondary source together are not able to meet the load demand then load shedding will be executed according to the priority set. Thus the developed MAS algorithm co-ordinates the hybrid system components and achieves energy management among renewable energy sources, storage units, and load under varying environmental conditions and varying loads. STATCOM based compensation has been implemented to balance the reactive power demand and to mitigate the voltage fluctuations and harmonics on the AC bus. The proposed microgrid has been simulated with MAS concept in Matlab/Simulink environment. The results presented in this paper show cases the effectiveness of the proposed energy management controller.

30 citations


Journal ArticleDOI
TL;DR: In this article, a hybrid taguchi-grey relational approach is used to determine the optimum machining parameters over measured responses such as wear, roughness, and material removed, and experiments with optimum conditions show a better improvement in the output conditions.
Abstract: Machinability evaluation of Al–4%Cu–7.5%SiC metal matrix composite (MMC) prepared by powder metallurgy (P/M) process is presented. Specimens are prepared with 99.85% pure aluminum added with 4% copper and 7.5% silicon carbide particles by volume fraction. Scanning electron microscope image shows even distribution of particles in Al-MMC. Turning operation is performed by varying machining parameters and experiments are designed using Taguchi’s Design of Experiments (DoE), an L9 Orthogonal Array (OA) is chosen. A hybrid Taguchi–Grey relational approach is used to determine the optimum parameters over measured responses flank wear, roughness, and material removed. Analysis of Variance (ANOVA) result shows that the depth of cut is the influential parameter that contributes toward output responses. A metaheuristic evolutionary algorithm nondominated sorting genetic algorithm (NSGA-II) is applied to optimize the machining parameters for minimizing wear and maximizing metal removal. Experiments with optimum conditions show a better improvement in the output conditions.

28 citations


Journal ArticleDOI
TL;DR: In this article, the experimental results of the performance behavior of POFA in developing physical and mechanical properties of prepacked aggregate concrete were presented and the observation made in this study suggest that the replacement of OPC by POFA is beneficial, particularly for prepacked mass concrete where thermal cracking due to extreme heat rise is of great concern.
Abstract: Prepacked aggregate concrete (PAC) is a special type of concrete which is made by placing coarse aggregate in a formwork and injecting a grout either by pump or under the gravity force to fill the voids. Use of pozzolanic materials in conventional concrete has become increasingly extensive, and this trend is expected to continue in PAC as well. Palm oil fuel ash (POFA) is one of these pozzolanic ash, which has been recognized as a good pozzolanic material. This paper presents the experimental results of the performance behaviour of POFA in developing physical and mechanical properties of prepacked aggregate concrete. Four concrete mixes namely, prepacked concrete with 100% OPC as a control, and PAC with 10, 20 and 30% POFA were cast, and the temperature growth due to heat of hydration and heat transfer in all the mixtures was recorded. It has been found that POFA significantly reduces the temperature rise in prepacked aggregate concrete and delay the transfer of heat to the concrete body. The compressive and tensile strengths, however, increased with replacement up to 20% POFA. The results obtained and the observation made in this study suggest that the replacement of OPC by POFA is beneficial, particularly for prepacked mass concrete where thermal cracking due to extreme heat rise is of great concern.

Journal ArticleDOI
TL;DR: In this paper, a second order regression response surface model (RSM) and ant colony optimization (ACO) were combined to optimize the media compositions so as to enhance the productivity of lipopeptide.
Abstract: Central composite rotatable design (CCRD) of experiments was used to obtain data for Lipopeptide and Biomass concentrations from fermentation medium containing the following five components: glucose, monosodium glutamate, yeast extract, MgSO4⋅7H2O, and K2HPO4. Data was used to develop a second order regression response surface model (RSM) which was coupled with ant colony optimization (ACO) to optimize the media compositions so as to enhance the productivity of lipopeptide. The optimized media by ACO was found to yield 1.501 g/L of lipopeptide concentration which was much higher compared to 1.387 g/L predicted by Nelder–Mead optimization (NMO). The optimum from ACO was validated experimentally. RSM-based ACO is thus shown to be an effective tool for medium optimization of biosurfactant production.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the scour around circular bridge piers with two different diameters and different inclination angles toward downstream and found that an increase in the inclination angle leads to a significant decrease in the sediment ridge and scour hole dimensions.
Abstract: A fundamental principle in the safe design of bridge piers is to estimate maximum scour depth. As such, many researchers devoted their efforts to study the phenomenon of scour around bridge piers and to present relationships to estimate maximum scour depth. In the current research, scour around circular bridge piers with two different diameters and different inclination angles toward downstream has been investigated experimentally under clear water and different discharges. The obtained results revealed that increase in the inclination angle leads to a significant decrease in the scour depth, dimensions of sediment ridge and scour hole. Moreover, by comparing the data obtained from vertical bridge pier and well-known relationships, a relationship having the most agreement with the results was selected and modified to estimate equilibrium scour depth around inclined piers.

Journal ArticleDOI
TL;DR: In this article, a new approach to eliminate the non-possible assembly sequences based on liaisons is described and the correctness of the methodology is illustrated with an example, the methodology to obtain the feasible assembly sequences is also briefly described and presented.
Abstract: Selection of optimized assembly sequence from the available feasible assembly sequences is significantly essential to achieve cost-effective manufacturing process. To achieve this, at the outset, generation of feasible assembly sequences with topological, geometrical, precedence and stability conditions should be generated. The increase of part count in a product results huge number of assembly sequences, the Liaison matrix/Liaison graph generated based on the connections between the assembly components eliminates non-possible assembly sequences at the initial phase. There exist methods namely cut-set method to eliminate the non-possible assembly sequences using liaison graph. In this paper a new approach to eliminate the non-possible assembly sequences based on liaisons is described and the correctness of the methodology is illustrated with an example. The methodology to obtain the feasible assembly sequences is also briefly described and presented. An algorithm to interface with the CAD environment is described briefly.

Journal ArticleDOI
TL;DR: In this article, an emphasis has been given to review the effects of various operating and geometric parameters, and thermodynamic optimization on the performance of a solar still, including the second law of thermodynamics.
Abstract: The solar still is gaining popularity among the scientific community for the production of distillate and fluoride free water due to its low cost and simple working principle. Continuous efforts have been made by various researchers to increase its productivity. Various techniques and configurations have been attempted in the literature to enhance the efficiency of the solar still. Many researchers have also studied different parameters influencing the performance of solar stills. Thermodynamic analysis, such as, energy balance and losses by using the second law of thermodynamics have also been reported in the literature. However, optimum combinations of the operating parameters in addition to thermodynamic optimization for high distillate yield as well as the efficiency have not been thoroughly studied in the literature. In the present work, an emphasis has been given to review the effects of various operating and geometric parameters, and thermodynamic optimization on the performance of a solar still.

Journal ArticleDOI
TL;DR: In this paper, the effects of blast furnace slag, different water/(cement + mineral additive) ratios and pumice aggregates on some physical and mechanical properties of self-compacting lightweight aggregate concrete were investigated.
Abstract: This paper presents the results of an experimental study of the effects of blast furnace slag, different water/(cement + mineral additive) ratios and pumice aggregates on some physical and mechanical properties of self-compacting lightweight aggregate concrete. In this study, pumice was used as lightweight aggregate. Several properties of self-compacting pumice aggregate lightweight concretes, such as unit weight, flow diameter, T50 time, flow diameter after an hour, V-funnel time, and L-box tests, 7, 28, 90 and 180-day compressive strength, 28-day splitting tensile strength, dry unit weight, water absorption, thermal conductivity and ultrasonic pulse velocity tests, were conducted. For this purpose, 18 series of concrete samples were prepared in two groups. In the first group, pumice aggregate at 100% replacement of natural aggregate was used in the production of self-compacting lightweight aggregate concrete with constant w/(c + m) ratios as 0.35, 0.40, and 0.45 by weight. Furthermore, as a second group, pumice aggregate was used as a replacement of natural aggregate, at the levels of 0, 20, 40, 60, 80, and 100% by volume. Flow diameters, T50 times, paste volumes, 28-day compressive strengths, dry unit weights, thermal conductivities and ultrasonic pulse velocity of self-compacting lightweight aggregate concrete were obtained over the range of 600–770 mm, 3–9 s, 435–540 l/m 3, 10.6–65.0 MPa, 845–2278 kg/m 3, 0.363–1.694 W/mK and 2617–4770 m/s respectively, which satisfies not only the strength requirement of semi-structural lightweight concrete but also the flowing ability requirements and thermal conductivity requirements of self-compacting lightweight aggregate concrete.

Journal ArticleDOI
TL;DR: A detailed review of the past studies carried out on crushing and energy absorption behavior of hollow and foam filled tubes under axial compression is presented in this article, which includes various parameters affecting the peak load and energy absorbing.
Abstract: Herein, a detailed review of the past studies carried out on crushing and energy absorption behaviour of hollow and foam filled tubes under axial compression is presented. Importance of such investigation is discussed for understanding the research need and to develop suitable alternatives. The focus of review is the deformation mechanism and energy absorption of hollow circular and square tubes, foam filled circular and square tubes notably. Comprehensive review on the various deformation modes for these tubes under axial impact load and effect of foam filling is presented. The review includes the various parameters affecting the peak load and energy absorption. Although various other forms of energy absorbing materials and structures exist such as composites, multi-wall tubes and honeycombs, these are not within the scope of present review. This paper intends to provide assistance in design and development of empty and foam filled tubes as effective energy absorbers. Further, this paper provides the necessary information for designers to understand the deformation of such tubes.

Journal ArticleDOI
TL;DR: The proposed improved method to detect R-peak using Shannon energy envelope outperforms other well-known methods in case of pathological ECG signals and is validated using 48 first channel ECG records of the MIT-BIH arrhythmia database.
Abstract: R-peaks in electrocardiogram (ECG) play a vital role in diagnosis of heart rhythm irregularities and also estimating heart rate variability. However, almost all existing R-peak detectors suffer from the non-stationary of both QRS morphology and noise. To overcome these difficulties, we propose a four-stage improved method to detect R-peak using Shannon energy envelope. In the first stage, noise is suppressed and QRS complex is enhanced by using band pass filter, first order differentiation, and amplitude normalization. In the second stage, Shannon energy envelope is extracted. In the third stage, peak is estimated without considering any threshold amplitude. In the final stage, true R-peaks are detected. Our proposed R-peak detection method is validated using 48 first channel ECG records of the MIT-BIH arrhythmia database with the accuracy of 99.84%, sensitivity of 99.95% and positive predictability of 99.88%. Our proposed method outperforms other well-known methods in case of pathological ECG signals.

Journal ArticleDOI
TL;DR: In this article, the authors presented the development of multiple regression analysis (MRA) and artificial neural network (ANN) models to predict weld bead geometry and HAZ width in submerged arc welding process.
Abstract: Weld bead plays an important role in determining the quality of welding particularly in high heat input processes. This research paper presents the development of multiple regression analysis (MRA) and artificial neural network (ANN) models to predict weld bead geometry and HAZ width in submerged arc welding process. Design of experiments is based on Taguchi’s L16 orthogonal array by varying wire feed rate, transverse speed and stick out to develop a multiple regression model, which has been checked for adequacy and significance. Also, ANN model was accomplished with the back propagation approach in MATLAB program to predict bead geometry and HAZ width. Finally, the results of two prediction models were compared and analyzed. It is found that the error related to the prediction of bead geometry and HAZ width is smaller in ANN than MRA.

Journal ArticleDOI
TL;DR: Reference recursive recipe (RRR) as discussed by the authors utilizes the prior, posterior, and smoothed state estimates as well as their covariances to balance the state and measurement equations and thus form generalized cost functions.
Abstract: Since the innovation of the ubiquitous Kalman filter more than five decades back it is well known that to obtain the best possible estimates the tuning of its statistics , , , R and Q namely initial state and covariance, unknown parameters, and the measurement and state noise covariances is very crucial. The manual and other approaches have not matured to a routine approach applicable for any general problem. The present reference recursive recipe (RRR) utilizes the prior, posterior, and smoothed state estimates as well as their covariances to balance the state and measurement equations and thus form generalized cost functions. The filter covariance at the end of each pass is heuristically scaled up by the number of data points and further trimmed to provide the for subsequent passes. The importance of as the probability matching prior between the frequentist approach via optimization and the Bayesian approach of the Kalman filter is stressed. A simultaneous and proper choice for Q and R based on the filter sample statistics and other covariances leads to a stable filter operation after a few iterations. A typical simulation study of a spring, mass and damper system with a weak nonlinear spring constant by RRR shows it to be better than earlier techniques. Part-2 of the paper further consolidates the present approach based on an analysis of real flight test data.

Journal ArticleDOI
TL;DR: An ontological based approach is proposed following first-order logic (FOL) rules to identify defects namely dead features and false optional features that represent variability of SPL and therefore improves SPL.
Abstract: Software product line (SPL) is an emergent strategy for generating software products. The variability and commonality of SPL is illustrated by feature models (FMs). The quality of software products relies on the correctness of SPL. The overall benefits of software product line engineering (SPLE) are reduced by various kinds of defects such as dead features and false optional features in an FM. These defects can be inherited in the software products built from a defective product line model (PLM). In this paper, the problem of enhancing the quality of software products derived from SPLE is handled. An ontological based approach is proposed following first-order logic (FOL) rules to identify defects namely dead features and false optional features. The classification of cases for these defects in FMs that represent variability of SPL is defined. The presented approach has been explained with the help of an FM derived from the standard case in product line (PL) community. The initial empirical evaluation of the proposed approach analyses 35 FMs with different sizes. The results obtained exhibit that the proposed approach is accurate, effective, scalable up to 200 features and therefore improves SPL.

Journal ArticleDOI
TL;DR: In this article, an attempt was made to improve the energy and exergy performance of solar air heater by employing double pass with different absorber surface geometries (roughened, finned, and v-corrugated wire mesh) in the second pass, and also by mounting longitudinal fins in the back side of the absorber plate (first pass).
Abstract: In this study, an attempt is made to improve the energy and exergy performance of solar air heater by employing double pass with different absorber surface geometries (roughened, finned, and v-corrugated wire mesh) in the second pass, and also by mounting longitudinal fins in the back side of the absorber plate (first pass). The effect of varied mass flow rate and solar intensity on temperature rise of air, energy efficiency, exergy gain and pressure drop at steady state condition was determined for different types of solar air heaters utilizing an indoor solar simulator. The temperature rise of air, thermal efficiency and exergy gain depends on mass flow rate, surface geometries of absorber and solar intensity, whereas the pressure drop depends on mass flow rate and surface geometries of absorber.

Journal ArticleDOI
TL;DR: In this article, a high head model Francis turbine operating at 50% load pressure measurements have been carried out experimentally on a modelFrancis turbine and it is observed that the turbine experiences significant pressure fluctuations at the vaneless space and the runner, and a standing wave is observed between the pressure tank outlet and the turbine inlet.
Abstract: Hydraulic turbines are operating at part load conditions depending on availability of hydraulic energy or to meet the grid requirements The turbine experiences more fatigue during the part load operating conditions due to flow phenomena such as vortex breakdown in the draft tube and flow instability in the runner The present paper focuses on the investigation of a high head model Francis turbine operating at 50% load Pressure measurements have been carried out experimentally on a model Francis turbine Total six pressure sensors were mounted inside the turbine and other two pressure sensors were mounted at the turbine inlet pipe It is observed that the turbine experiences significant pressure fluctuations at the vaneless space and the runner Moreover, a standing wave is observed between the pressure tank outlet and the turbine inlet Analysis of the data acquired by the pressure sensors mounted in the draft tube showed the presence of vortex breakdown co-rotating with the runner The detailed analysis showed the rotating and plunging components of the vortex breakdown The influence of the rotating component was observed in the entire hydraulic circuit including distributor and turbine inlet but not the plunging one

Journal ArticleDOI
TL;DR: In this article, the tensile properties of hybrid composite made by intruding unidirectional banana and glass fibers into epoxy resin mixture were analyzed using the ANSYS.
Abstract: In present day scenario, moving towards an environment friendly material is a key issue for manufacturing industries in order to provide suitable alternatives for the existing conventional materials Natural fibers have higher economic impact and miniature in density when compared to glass fibers while making composites Though the strength of natural fibers is not as high as glass fibers, their specific properties are comparable In this paper a study has been carried out to find the tensile characteristics of hybrid composite made by intruding unidirectional banana and glass fibers into epoxy resin mixture The hand lay-up method of fabrication was employed in preparing the composites of unidirectional glass fiber (UGF) and unidirectional banana/glass fiber (U B/G F) Tensile properties of the composites are verified using ANSYS It is observed from the findings that the numerical analysis is found to be higher than experimental analysis Hybridization of banana fiber shows better tensile properties It is evident from the result that, comparatively equal displacement is obtained for the varying load for both the composites The surface morphology of the tested composites is analyzed through scanning electron microscope (SEM)

Journal ArticleDOI
TL;DR: In this article, the authors review and validate the findings of Odgaard and his associates by utilizing computational fluid dynamics and experiments as a tool in which the vane generated vorticity in the downstream was maximized in order to obtain optimum vane parameters for single and multiple vane arrays.
Abstract: Submerged vanes are airfoils which are in general placed at certain angle with respect to the flow direction in a channel to induce artificial circulations downstream. By virtue of these artificially generated circulations, submerged vanes were utilized to protect banks of rivers against erosion, to control shifting of rivers, to avoid blocking of lateral intake with sediment deposition, etc. Odgaard and his associates have experimentally obtained the optimum vane sizes and recommended that it can be used for vane design. This paper is an attempt to review and validate the findings of Odgaard and his associates by utilizing computational fluid dynamics and experiments as a tool in which the vane generated vorticity in the downstream was maximized in order to obtain optimum vane parameters for single and multiple vane arrays.

Journal ArticleDOI
TL;DR: It is proposed in the paper that the use of data hiding methods in terms of access security in cloud computing architecture and the security of the stored data would be very effective in securing information.
Abstract: Cloud computing is one of the largest developments occurred in the field of information technology during recent years. This model has become more desirable for all institutions, organizations and also for personal use thanks to the storage of ‘valuable information’ at low costs, access to such information from anywhere in the world as well as its ease of use and low cost. In this paper, the services constituting the cloud architecture and deployment models are examined, and the main factors in the provision of security requirements of all those models as well as points to be taken into consideration are described in detail. In addition, the methods and tools considering how security, confidentiality and integrity of the information or data that forms the basis of modern technology are implemented in cloud computing architecture are examined. Finally, it is proposed in the paper that the use of data hiding methods in terms of access security in cloud computing architecture and the security of the stored data would be very effective in securing information.

Journal ArticleDOI
TL;DR: In this article, a suspended coil, a wound coil, and a permanent magnet are used to extract acoustical energy from a magnet holder in an electromagnetic energy harvester.
Abstract: This paper reports a suspended coil, electromagnetic acoustic energy harvester (AEH) for extracting acoustical energy. The developed AEH comprises Helmholtz resonator (HR), a wound coil bonded to a flexible membrane and a permanent magnet placed in a magnet holder. The harvester’s performance is analyzed under different sound pressure levels (SPLs) both in laboratory and in real environment. In laboratory, when connected to 50 Ω load resistance and subjected to an SPL of 100 dB, the AEH generated a peak load voltage of 198.7 mV at the resonant frequency of 319 Hz. When working under the optimum load resistance, the AEH generated an optimum load power of 789.65 µW. In real environment, the developed AEH produced a maximum voltage of 25 mV when exposed to the acoustic noise of a motorcycle and generated an optimum voltage of 60 mV when it is placed in the surroundings of a domestic electrical generator.

Journal ArticleDOI
TL;DR: An extensive literature review of the application of GA on supply chain management (SCM) and eight processes as given by Council of SCM Professionals (CSCMF) are considered.
Abstract: Genetic algorithms (GAs) are perhaps the oldest and most frequently used search techniques for dealing with complex and intricate real-life problems that are otherwise difficult to solve by the traditional methods. The present article provides an extensive literature review of the application of GA on supply chain management (SCM). SCM consists of several intricate processes and each process is equally important for maintaining a successful supply chain. In this paper, eight processes (where each process has a set of sub-processes) as given by Council of SCM Professionals (CSCMF) are considered. The idea is to review the application of GA on these aspects and to provide the readers a detailed study in this area. The authors have considered more than 220 papers covering a span of nearly two decades for this study. The analysis is shown in detail with the help of graphs and tables. It is expected that such an extensive study will encourage and motivate the fellow researchers working in related area; to identify the gaps and to come up with innovative ideas.

Journal ArticleDOI
TL;DR: It has been found that increasing radial/angular resolution, with normalization in place, improves EER for proposed iris recognition system and there is a significant improvement in equal error rate (EER) when number of statistical parameters for feature extraction is increased.
Abstract: Iris recognition systems have been proposed by numerous researchers using different feature extraction techniques for accurate and reliable biometric authentication. In this paper, a statistical feature extraction technique based on correlation between adjacent pixels has been proposed and implemented. Hamming distance based metric has been used for matching. Performance of the proposed iris recognition system (IRS) has been measured by recording false acceptance rate (FAR) and false rejection rate (FRR) at different thresholds in the distance metric. System performance has been evaluated by computing statistical features along two directions, namely, radial direction of circular iris region and angular direction extending from pupil to sclera. Experiments have also been conducted to study the effect of number of statistical parameters on FAR and FRR. Results obtained from the experiments based on different set of statistical features of iris images show that there is a significant improvement in equal error rate (EER) when number of statistical parameters for feature extraction is increased from three to six. Further, it has also been found that increasing radial/angular resolution, with normalization in place, improves EER for proposed iris recognition system.

Journal ArticleDOI
TL;DR: In this article, an integrated solar heat pipe wall space heating system, employing double glazed heat pipe evacuated tube solar collector and forced convective heat transfer condenser, is introduced.
Abstract: In this paper, an integrated solar heat pipe wall space heating system, employing double glazed heat pipe evacuated tube solar collector and forced convective heat transfer condenser, is introduced. Thermal performance of the heat pipe solar collector is studied and a numerical model is developed to investigate the thermal efficiency of the system, the inlet and outlet air temperatures and heat pipe temperature. Furthermore, the system performance is evaluated based on exergy efficiency. In order to verify the precision of the developed model, the numerical results are compared with experimental data. Parametric sensitivity for design features and material associated with the heat pipe, collector cover and insulation is evaluated to provide a combination with higher thermal performance. Simulation results show that applying a solar collector with more than 30 heat pipes is not efficient. The rate of increasing in temperature of air becomes negligible after 30 heat pipes and the trend of the thermal efficiency is descending with increasing heat pipes. The results also indicate that at a cold winter day of January, the proposed system with a 20 heat pipe collector shows maximum energy and exergy efficiency of 56.8% and 7.2%, which can afford warm air up to 30°C. At the end, the capability of the proposed system to meet the heating demand of a building is investigated. It is concluded that the best method to reach a higher thermal covered area is to apply parallel collectors.