Browsing by Author "Gupta, A."

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A green greedy process scheduler for cloud data centers
(Institute of Electrical and Electronics Engineers Inc., 2014) Karthik, C.; Gupta, A.; Chandrasekaran, K.
In this paper we have addressed a major problem in current day data centers- power consumption. Power consumption in data centers has become a major problem these days, both from economic and environmental perspective. Various factors affect the power consumption, one of them being the scheduling of tasks on the data center servers. Basically we achieved a real-time simulation of two cloud scheduling algorithms and compared the power efficiency of the two algorithms in terms of two main temperature parameters of the servers-idle temperature and critical temperature. We assumed that we were given all the task parameters such as running time etc. and then we calculated a final temperature that a system will reach on running that particular task. Then we decided which system could accommodate that task based on that systems critical temperature and chose the best system among those based on a score proposed in the paper. Â© 2014 IEEE.
A Review on Carotid Ultrasound Atherosclerotic Tissue Characterization and Stroke Risk Stratification in Machine Learning Framework
(Current Medicine Group LLC 1 info@phl.cursci.com, 2015) Sharma, A.M.; Gupta, A.; Kumar, P.K.; Rajan, J.; Saba, L.; Nobutaka, I.; Laird, J.R.; Nicolades, A.; Suri, J.S.
Cardiovascular diseases (including stroke and heart attack) are identified as the leading cause of death in today’s world. However, very little is understood about the arterial mechanics of plaque buildup, arterial fibrous cap rupture, and the role of abnormalities of the vasa vasorum. Recently, ultrasonic echogenicity characteristics and morphological characterization of carotid plaque types have been shown to have clinical utility in classification of stroke risks. Furthermore, this characterization supports aggressive and intensive medical therapy as well as procedures, including endarterectomy and stenting. This is the first state-of-the-art review to provide a comprehensive understanding of the field of ultrasonic vascular morphology tissue characterization. This paper presents fundamental and advanced ultrasonic tissue characterization and feature extraction methods for analyzing plaque. Additionally, the paper shows how the risk stratification is achieved using machine learning paradigms. More advanced methods need to be developed which can segment the carotid artery walls into multiple regions such as the bulb region and areas both proximal and distal to the bulb. Furthermore, multimodality imaging is needed for validation of such advanced methods for stroke and cardiovascular risk stratification. © 2015, Springer Science+Business Media New York.
Accurate lumen diameter measurement in curved vessels in carotid ultrasound: an iterative scale-space and spatial transformation approach
(2017) Krishna, Kumar, P.; Araki, T.; Rajan, J.; Saba, L.; Lavra, F.; Ikeda, N.; Sharma, A.M.; Shafique, S.; Nicolaides, A.; Laird, J.R.; Gupta, A.; Suri, J.S.
Monitoring of cerebrovascular diseases via carotid ultrasound has started to become a routine. The measurement of image-based lumen diameter (LD) or inter-adventitial diameter (IAD) is a promising approach for quantification of the degree of stenosis. The manual measurements of LD/IAD are not reliable, subjective and slow. The curvature associated with the vessels along with non-uniformity in the plaque growth poses further challenges. This study uses a novel and generalized approach for automated LD and IAD measurement based on a combination of spatial transformation and scale-space. In this iterative procedure, the scale-space is first used to get the lumen axis which is then used with spatial image transformation paradigm to get a transformed image. The scale-space is then reapplied to retrieve the lumen region and boundary in the transformed framework. Then, inverse transformation is applied to display the results in original image framework. Two hundred and two patients left and right common carotid artery (404 carotid images) B-mode ultrasound images were retrospectively analyzed. The validation of our algorithm has done against the two manual expert tracings. The coefficient of correlation between the two manual tracings for LD was 0.98 (p < 0.0001) and 0.99 (p < 0.0001), respectively. The precision of merit between the manual expert tracings and the automated system was 97.7 and 98.7%, respectively. The experimental analysis demonstrated superior performance of the proposed method over conventional approaches. Several statistical tests demonstrated the stability and reliability of the automated system. 2016, International Federation for Medical and Biological Engineering.
Accurate lumen diameter measurement in curved vessels in carotid ultrasound: an iterative scale-space and spatial transformation approach
(Springer Verlag service@springer.de, 2017) Krishna Kumar, P.; Araki, T.; Rajan, J.; Saba, L.; Lavra, F.; Ikeda, N.; Sharma, A.M.; Shafique, S.; Nicolaïdes, A.; Laird, J.R.; Gupta, A.; Suri, J.S.
Monitoring of cerebrovascular diseases via carotid ultrasound has started to become a routine. The measurement of image-based lumen diameter (LD) or inter-adventitial diameter (IAD) is a promising approach for quantification of the degree of stenosis. The manual measurements of LD/IAD are not reliable, subjective and slow. The curvature associated with the vessels along with non-uniformity in the plaque growth poses further challenges. This study uses a novel and generalized approach for automated LD and IAD measurement based on a combination of spatial transformation and scale-space. In this iterative procedure, the scale-space is first used to get the lumen axis which is then used with spatial image transformation paradigm to get a transformed image. The scale-space is then reapplied to retrieve the lumen region and boundary in the transformed framework. Then, inverse transformation is applied to display the results in original image framework. Two hundred and two patients’ left and right common carotid artery (404 carotid images) B-mode ultrasound images were retrospectively analyzed. The validation of our algorithm has done against the two manual expert tracings. The coefficient of correlation between the two manual tracings for LD was 0.98 (p < 0.0001) and 0.99 (p < 0.0001), respectively. The precision of merit between the manual expert tracings and the automated system was 97.7 and 98.7%, respectively. The experimental analysis demonstrated superior performance of the proposed method over conventional approaches. Several statistical tests demonstrated the stability and reliability of the automated system. © 2016, International Federation for Medical and Biological Engineering.
An Efficient Bandwidth Management algorithm for WiMAX (IEEE 802.16) wireless network: EBM allocation algorithm
(2012) Gupta, A.; Chandavarkar, B.R.
IEEE 802.16 WiMAX (Worldwide Interoperability for Microwave Access) consists of five service classes with different priorities. The priority of real time traffic is higher than that of non-real time traffic. Since bandwidth is limited, it must be allocated in advance to guarantee the throughput of real time traffic in WiMAX network. But WiMAX standard does not provide any algorithm for dynamic allocation of bandwidth to these services. In this paper, a dynamic bandwidth allocation algorithm for WiMAX called Efficient Bandwidth Management (EBM) is proposed. In EBM the bandwidth will be increased in the upcoming frames when the allocated bandwidth is not sufficient to transfer the data. On the other side if the allocated bandwidth is more, then the bandwidth will be decreased in the upcoming frames so that the other services can use this excess bandwidth. This bandwidth increase or decrease is proportional to the remaining data in the queue. EBM increase the throughput of real time traffic as the bandwidth is handled efficiently. The proposed algorithm is implemented in ns-2 and results are compared with traditional IEEE 802.16 WiMAX. The simulation results show that EBM algorithm gives better result for real-time traffic. Â© 2012 IEEE.
Carotid inter-adventitial diameter is more strongly related to plaque score than lumen diameter: An automated tool for stroke analysis
(2016) Saba, L.; Araki, T.; Krishna, Kumar, P.; Rajan, J.; Lavra, F.; Ikeda, N.; Sharma, A.M.; Shafique, S.; Nicolaides, A.; Laird, J.R.; Gupta, A.; Suri, J.S.
Purpose: To compare the strength of correlation between automatically measured carotid lumen diameter (LD) and interadventitial diameter (IAD) with plaque score (PS). Methods: Retrospective study on a database of 404 common carotid artery B-mode sonographic images from 202 diabetic patients. LD and IAD were computed automatically using an advanced computerized edge detection method and compared with two distinct manual measurements. PS was computed by adding the maximal thickness in millimeters of plaques in segments taken from the internal carotid artery, bulb, and common carotid artery on both sides. Results: The coefficient of correlation was 0.19 (p < 0.007) between LD and PS, and 0.25 (p < 0.0006) between IAD and PS. After excluding 10 outliers, coefficient of correlation was 0.25 (p < 0.0001) between LD and PS, and 0.38 (p < 0.0001) between IAD and PS. The precision of merit of automated versus the two manual measurements was 96.6% and 97.2% for LD, and 97.7% and 98.1%, for IAD, respectively. Conclusions: Our automated measurement system gave satisfying results in comparison with manual measurements. Carotid IAD was more strongly correlated to PS than carotid LD in this population sample of Japanese diabetic patients. 2016 Wiley Periodicals, Inc.
Carotid inter-adventitial diameter is more strongly related to plaque score than lumen diameter: An automated tool for stroke analysis
(John Wiley and Sons Inc. P.O.Box 18667 Newark NJ 07191-8667, 2016) Saba, L.; Araki, T.; Krishna Kumar, P.; Rajan, J.; Lavra, F.; Ikeda, N.; Sharma, A.M.; Shafique, S.; Nicolaïdes, A.; Laird, J.R.; Gupta, A.; Suri, J.S.
Purpose: To compare the strength of correlation between automatically measured carotid lumen diameter (LD) and interadventitial diameter (IAD) with plaque score (PS). Methods: Retrospective study on a database of 404 common carotid artery B-mode sonographic images from 202 diabetic patients. LD and IAD were computed automatically using an advanced computerized edge detection method and compared with two distinct manual measurements. PS was computed by adding the maximal thickness in millimeters of plaques in segments taken from the internal carotid artery, bulb, and common carotid artery on both sides. Results: The coefficient of correlation was 0.19 (p < 0.007) between LD and PS, and 0.25 (p < 0.0006) between IAD and PS. After excluding 10 outliers, coefficient of correlation was 0.25 (p < 0.0001) between LD and PS, and 0.38 (p < 0.0001) between IAD and PS. The precision of merit of automated versus the two manual measurements was 96.6% and 97.2% for LD, and 97.7% and 98.1%, for IAD, respectively. Conclusions: Our automated measurement system gave satisfying results in comparison with manual measurements. Carotid IAD was more strongly correlated to PS than carotid LD in this population sample of Japanese diabetic patients. © 2016 Wiley Periodicals, Inc.
Comparative study on sensitivities of different geometries of plastic optical fiber
(2014) Ganesh, S.; Sai, Shankar, M.; Kishore, P.V.N.; Abdul, Hakeem, P.V.; Gupta, A.; Divya, G.
This article discusses a comparative study on sensitivities of different geometries of Plastic optical fiber (POF). The evanescent field modulation decides the sensitivities of fiber geometries. Sensitivity increases with the increase of U-bents. � OSA 2016.
Comparative study on sensitivities of different geometries of plastic optical fiber
(Optica Publishing Group (formerly OSA), 2016) Ganesh, S.; Sai Shankar, M.; Kishore, P.V.N.; Abdul Hakeem, P.V.; Gupta, A.; Divya, G.
This article discusses a comparative study on sensitivities of different geometries of Plastic optical fiber (POF). The evanescent field modulation decides the sensitivities of fiber geometries. Sensitivity increases with the increase of U-bents. Â© OSA 2016.
Design and Analysis of a Thermal Flowmeter for Microfluidic Applications: A Study on Sensitivity at Low Flow Rates
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Raveesh, A.H.; Vemulapalli, S.; Gupta, A.; Santhosh, S.K.; Navada, B.R.
To address the challenge of precise flow rate measurement in microchannels, this research details the conceptualization and comprehensive evaluation of a thermal flowmeter which works on the principle of calorimetry for measuring small flow rates between 0.1 and 180 mL/h. The thermal flowmeter is composed of a silicone pipe, a heater, three platinum thermal sensors (T1, T2, T3), and water as the working fluid. The flowmeter is strategically placed to monitor the complex thermodynamics between upstream and downstream flows. The analysis revealed a notable decay in the slope of the temperature differences beyond a flow rate of 40 mL/h, indicating the exceptional sensitivity of the device at lower flow rates and making it an ideal choice for medical applications. Parametric analysis was also carried out to place the sensors at optimized locations for better sensitivity. © 2024 by the authors.
Effect of Heat Input on Microstructure and Corrosion Behavior of Duplex Stainless Steel Shielded Metal Arc Welds
(2018) Gupta, A.; Kumar, A.; Baskaran, T.; Arya, S.B.; Khatirkar, R.K.
In the present work, UNS S32750 super duplex stainless steel sheets were welded by shielded metal arc welding process with E2595 electrode using two different heat inputs, 0.54 and 1.10 kJ/mm. Microstructural investigations (optical and scanning electron microscopy) showed very small differences in the heat affected zone for both the heat inputs. The weld metals showed presence of three different morphologies of austenite Widmanstatten, intra-granular and grain boundary austenite along with ferrite. Ferrite content in the weld region was also nearly same and did not change significantly with the increase in heat input. Both the weldments showed similar mechanical properties (ultimate tensile strength, impact strength and hardness) and failed in a ductile manner. Electrochemical studies in 3.5% NaCl solution showed the degree of sensitization to less than 1% and nearly same pitting potential for both heat inputs. Since the effect of heat input on the weld behavior was negligible, low heat input may be preffered for welding UNS S32750 super duplex stainless steel. 2018, The Indian Institute of Metals - IIM.
Effect of Heat Input on Microstructure and Corrosion Behavior of Duplex Stainless Steel Shielded Metal Arc Welds
(Springer India, 2018) Gupta, A.; Kumar, A.; Baskaran, T.; Arya, S.B.; Khatirkar, R.K.
In the present work, UNS S32750 super duplex stainless steel sheets were welded by shielded metal arc welding process with E2595 electrode using two different heat inputs, 0.54 and 1.10 kJ/mm. Microstructural investigations (optical and scanning electron microscopy) showed very small differences in the heat affected zone for both the heat inputs. The weld metals showed presence of three different morphologies of austenite—Widmanstatten, intra-granular and grain boundary austenite along with ferrite. Ferrite content in the weld region was also nearly same and did not change significantly with the increase in heat input. Both the weldments showed similar mechanical properties (ultimate tensile strength, impact strength and hardness) and failed in a ductile manner. Electrochemical studies in 3.5% NaCl solution showed the degree of sensitization to less than 1% and nearly same pitting potential for both heat inputs. Since the effect of heat input on the weld behavior was negligible, low heat input may be preffered for welding UNS S32750 super duplex stainless steel. © 2018, The Indian Institute of Metals - IIM.
An Efficient Bandwidth Management algorithm for WiMAX (IEEE 802.16) wireless network: EBM allocation algorithm
(2012) Gupta, A.; Chandavarkar, B.R.
IEEE 802.16 WiMAX (Worldwide Interoperability for Microwave Access) consists of five service classes with different priorities. The priority of real time traffic is higher than that of non-real time traffic. Since bandwidth is limited, it must be allocated in advance to guarantee the throughput of real time traffic in WiMAX network. But WiMAX standard does not provide any algorithm for dynamic allocation of bandwidth to these services. In this paper, a dynamic bandwidth allocation algorithm for WiMAX called Efficient Bandwidth Management (EBM) is proposed. In EBM the bandwidth will be increased in the upcoming frames when the allocated bandwidth is not sufficient to transfer the data. On the other side if the allocated bandwidth is more, then the bandwidth will be decreased in the upcoming frames so that the other services can use this excess bandwidth. This bandwidth increase or decrease is proportional to the remaining data in the queue. EBM increase the throughput of real time traffic as the bandwidth is handled efficiently. The proposed algorithm is implemented in ns-2 and results are compared with traditional IEEE 802.16 WiMAX. The simulation results show that EBM algorithm gives better result for real-time traffic. � 2012 IEEE.
Energy Efficient Coverage Optimization in Mobile Wireless Sensor Network Using Grey Wolf Algorithm
(Institute of Electrical and Electronics Engineers Inc., 2023) Gupta, A.; Mamatha, K.M.; Manjappa, M.
The issue of decreased coverage rate in Mobile Wireless Sensor Networks (MWSNs), caused by mobile sensor nodes being randomly placed inside a monitoring area. Additionally, it becomes extremely important to utilise a sensor node's energy very effectively due to the finite energy of sensor nodes. Hence, to provide optimised positions for the sensor nodes while using the energy of sensor nodes adeptly authors propose an energy efficient coverage algorithm. Initially, article focus on optimal placement of the sensor nodes within a area to achieve the maximum coverage and later authors have focused on improvising the network lifetime. Article presents a combination of Grey Wolf Optimization and Virtual Force algorithm for optimization of coverage in MWSN. Further, to improve the network lifetime, a GWO-based clustering algorithm is presented using distance and energy as a parameter. The algorithms are implemented and simulated on Matlab. The efficiency of the presented algorithm is observed comparing with other Swarm Intelligence (SI) based optimization algorithms, like GWO, VFA, Particle Swarm Optimization (PSO), Genetic Algorithm (GA), and Ant-lion Optimization (ALO) and the results of the GWO-based clustering is compared with the traditional LEACH algorithm and energy-balanced clustering based on PSO. Simulation results demonstrate that the presented algorithms outperform the considered algorithms. Â© 2023 IEEE.
Experimental evaluation of the synergistic effect of calcium precursor dosage and bacterial strain interactions on the biogenic healing potential of self-healing cement mortar
(Taylor and Francis Ltd., 2024) Baby, B.; Palanisamy, T.; Gupta, A.; Gopal, M.
This study investigates the microbially induced calcium carbonate precipitation (MICP) in repair mortar, focusing on the impact of calcium precursor dosage and bacterial strain selection. C6H10CaO6·xH2O and (CH3COO)2Ca·xH2O were used as calcium precursors at dosages of 0.1, 0.25, and 0.4 M with Bacillus subtilis VEB4, Priestia megaterium TSB16, and Halobacillus halophilus MCC2188 microbes. Quantitative assessment of precipitate and optimization of precursor dosages were conducted before making mortar cube specimens of size 70.6 × 70.6 × 70.6 mm with bacterial spores and nutrients immobilized in Modified Expanded Perlite. Cracked cube specimens underwent automated wet-dry cycles of 12 h daily for 60 days to induce healing. Comparative analysis of biomortar specimens showed P. megaterium as the most effective in compressive strength recovery (up to 89.33%) and crack healing with a maximum healed crack width of 0.64 mm, followed by B. subtilis with significant CSR improvements. H. halophilus, less efficient in non-saline conditions, healed cracks up to 0.48 mm. Calcium lactate was considered the better calcium source choice for B. subtilis and P. megaterium strains, whereas calcium acetate improved MICP by H. halophilus. Microstructural analysis of healed precipitates collected from cracked cubes identified distinct morphology of MICP and the presence of polymorphs viz, calcite, aragonite, and vaterite. Tailored selection and dosage of calcium precursors for each strain significantly enhanced MICP and improved the quality of healing products in cracks, advancing the understanding of self-healing construction biomaterials. © 2024 Informa UK Limited, trading as Taylor & Francis Group.
A green greedy process scheduler for cloud data centers
(2014) Karthik, C.; Gupta, A.; Chandrasekaran, K.
In this paper we have addressed a major problem in current day data centers- power consumption. Power consumption in data centers has become a major problem these days, both from economic and environmental perspective. Various factors affect the power consumption, one of them being the scheduling of tasks on the data center servers. Basically we achieved a real-time simulation of two cloud scheduling algorithms and compared the power efficiency of the two algorithms in terms of two main temperature parameters of the servers-idle temperature and critical temperature. We assumed that we were given all the task parameters such as running time etc. and then we calculated a final temperature that a system will reach on running that particular task. Then we decided which system could accommodate that task based on that systems critical temperature and chose the best system among those based on a score proposed in the paper. � 2014 IEEE.
Influence of perforation pattern in Direct Strength Method of upright design
(Structural Stability Research Council, 2021) Jeyapragasam, J.V.V.; Gupta, A.; Harisanth, K.S.; Jayachandran, S.A.
The Direct Strength Method design of thin-walled cold-formed steel members is recently extended to perforated members and implemented in AISI-2016 specification. Albeit the background research is well constructed for discrete perforations, it requires more attention to pattern perforations. Perhaps the range of upright cross-sections and perforation shapes available in the market are patented, is the main reason for the lack of experimental data in this research domain. Available literature reports a pool of numerical data resulting from finite element analysis accounting the parameters such as cross-section shape, thickness, perforation shape, the spacing between perforations, member lengths, etc. These numerical models are mainly calibrated with the experimental results of fixed end columns. It should be noted that the fixed end columns are not influenced by the shift of effective centroid. Using such results in developing analytical equations will end up with the ignorance of effective centroid shift. The systematic experiments on perforated compression members in the view of simply supported boundary conditions are scarce. Therefore, experimental results with respect to flexural boundary conditions are reported herein. With the results of experiments, the influence of perforations is rationally assessed for local, distortional and flexural buckling about minor axis. The interaction between the modes is also observed and reported. The DSM design procedure recommended in the AISI-2016 is validated with the experimental results and summarized for the safe and economic design of uprights. Â© 2021 Proceedings of the Annual Stability Conference Structural Stability Research Council 2021, SSRC 2021. All rights reserved.
IntelliSearch: A search engine based on Big Data analytics integrated with crowdsourcing and category-based search
(2015) Lakhani, A.; Gupta, A.; Chandrasekaran, K.
Big Data is the technology that has changed the world. Its powerful abilities to process the data and generate the valuable data out of that has challenged the saying wisdom can be only possessed by those who have souls. Though the big data analytics is quite successful in mining the value out of the large pool of data but Big Data alone is not enough in case of web-analytics. The existing search engines lack the category based search feature and a standard ranking system for website. Crowdsourcing by involving active online community on internet is changing the shape of web applications by refining the data and improving the recommendations for the products. The paper discusses about the search engines, web-analytics toolbars and crowdsourcing to improve the web-analytics. The paper also discusses how integration of crowdsourcing with Big Data Analytics can result in 'IntelliSearch', a robust and reliable search engine. � 2015 IEEE.
IntelliSearch: A search engine based on Big Data analytics integrated with crowdsourcing and category-based search
(Institute of Electrical and Electronics Engineers Inc., 2015) Lakhani, A.; Gupta, A.; Chandrasekaran, K.
Big Data is the technology that has changed the world. Its powerful abilities to process the data and generate the valuable data out of that has challenged the saying wisdom can be only possessed by those who have souls. Though the big data analytics is quite successful in mining the value out of the large pool of data but Big Data alone is not enough in case of web-analytics. The existing search engines lack the category based search feature and a standard ranking system for website. Crowdsourcing by involving active online community on internet is changing the shape of web applications by refining the data and improving the recommendations for the products. The paper discusses about the search engines, web-analytics toolbars and crowdsourcing to improve the web-analytics. The paper also discusses how integration of crowdsourcing with Big Data Analytics can result in 'IntelliSearch', a robust and reliable search engine. Â© 2015 IEEE.
Long-lasting Bacillus safensis CG1 and Bacillus cereus DKBovi-5 based coconut shell biochar spore composites as self-healing additives for bio-mortar production
(Elsevier B.V., 2024) Anoop, P.P.; Palanisamy, T.; Gupta, A.; Gopal, M.
The major challenge in the production of bio-mortar lies in the effective storage of immobilised bacterial carriers. This study explores the effective storage and use of coconut shell biochar as a carrier for bacterial spores. Bacillus safensis CG1 and Bacillus cereus DKBovi-5 were immobilised in biochar and stored at 4 °C and 25 °C for 120 days. The storage at 4 °C showed enhanced viability, and Field Emission Gun Scanning Electron Microscopy studies revealed the firm adherence of bacterial spores within the biochar pores, attributed to the secretion of extracellular polymeric substances. Biochar-based spore composites stored at 4 °C were subsequently added as self-healing additives in mortar. Mechanical, self-healing, and microstructural evaluations demonstrated that the biochar with Bacillus cereus DKBovi-5 exhibited superior results. Cracks up to 0.888 mm were healed within 56 days, indicating enhanced healing efficiency, as supported by higher ultrasonic pulse velocity and a lower resistivity ratio. Brunauer-Emmett-Teller 20-point adsorption-desorption analysis showed that biochar with Bacillus cereus DKBovi-5 mix possessed the smallest pore width of 3.086 nm. Additionally, Field Emission Gun Scanning Electron Microscopy- Energy Dispersive X-ray Spectroscopy, X-ray Diffraction, and Fourier Transform Infrared Spectroscopy analyses confirmed the formation of biogenic calcium carbonate in the healed regions. Overall, the biochar composite with Bacillus cereus DKBovi-5 showed significantly improved performance compared to Bacillus safensis CG1 and is recommended as a long-lasting self-healing additive for large-scale construction applications. © 2024 Elsevier B.V.