Concrete, an integral part of a nuclear power plant (NPP), experiences degradation during their o... more Concrete, an integral part of a nuclear power plant (NPP), experiences degradation during their operational lifetime of the plant. In this review, the major causes of concrete degradation are extensively discussed including mechanisms that are specific to NPPs. The damage mechanism could be chemical or physical. The major causes of chemical degradation include alkali–aggregate reactions, leaching, sulfate attack, bases and acids attack, and carbonation. Physical degradation is a consequence of both environmental and mechanical factors combined. These factors are mainly elevated temperature, radiation, abrasion and erosion, salt crystallization, freeze–thaw distortions, fatigue and vibration. Additionally, steel reinforcements, prestressing steels, liner plates, and structural steel also experience degradation. The prospective areas in the structural components of the NPP where the degradation could occur are mentioned and the effective solutions to the causes of degradation are high...
The wide applicability of acoustics in the life of mankind spread over health, energy, environmen... more The wide applicability of acoustics in the life of mankind spread over health, energy, environment, etc. These acoustic technologies rely on the materials properties with which are made of. However,...
Zenodo (CERN European Organization for Nuclear Research), May 23, 2009
This paper presents the design, fabrication and evaluation of magneto-rheological damper. Semi-ac... more This paper presents the design, fabrication and evaluation of magneto-rheological damper. Semi-active control devices have received significant attention in recent years because they offer the adaptability of active control devices without requiring the associated large power sources. Magneto-Rheological (MR) dampers are semi-active control devices that use MR fluids to produce controllable dampers. They potentially offer highly reliable operation and can be viewed as fail-safe in that they become passive dampers if the control hardware malfunction. The advantage of MR dampers over conventional dampers are that they are simple in construction, compromise between high frequency isolation and natural frequency isolation, they offer semi-active control, use very little power, have very quick response, has few moving parts, have a relax tolerances and direct interfacing with electronics. Magneto-Rheological (MR) fluids are Controllable fluids belonging to the class of active materials that have the unique ability to change dynamic yield stress when acted upon by an electric or magnetic field, while maintaining viscosity relatively constant. This property can be utilized in MR damper where the damping force is changed by changing the rheological properties of the fluid magnetically. MR fluids have a dynamic yield stress over Electro-Rheological fluids (ER) and a broader operational temperature range. The objective of this papert was to study the application of an MR damper to vibration control, design the vibration damper using MR fluids, test and evaluate its performance. In this paper the Rheology and the theory behind MR fluids and their use on vibration control were studied. Then a MR vibration damper suitable for vehicle suspension was designed and fabricated using the MR fluid. The MR damper was tested using a dynamic test rig and the results were obtained in the form of force vs velocity and the force vs displacement plots. The results were encouraging and greatly inspire further research on the topic.
Indian Scientific Journal Of Research In Engineering And Management, Mar 4, 2023
An up-to-date overview of various technologies which are existing to provide home automation from... more An up-to-date overview of various technologies which are existing to provide home automation from different sources is provided. This review covers some evolving technologies in the field of home automation using COB AC LED. A separate review on home automation and COB AC LED is provided. The use of regular LED in various domains is more expensive than the newly developed driverless AC LED, the total cost to build a driverless AC LED and the life span is much higher than the regular LED devices. This paper compared the performance of different ways of home and different ways of controlling the appliances.
Journal of Global Research in Computer Sciences, Mar 6, 2011
Social network gains popularity due to its ease of use, as an application of Web 2.0. The study o... more Social network gains popularity due to its ease of use, as an application of Web 2.0. The study of networks is an active area of research due to its capability of modelling many real world complex systems. One such interesting property to investigate in any typical network is the community structure which is the division of networks into groups. Discovering communities in a social network environment is graph partitioning problem, which subdivides the entire graph into smaller partitions. Graph partitioning is believed as NP -hard problem, due to its complexity to split the number of vertices. We introduced the method of mutual accessibility to find communities in social networking environments. Existing work presents community discovery from blog posts. In this research, we discovered community structures from blogs which are posted by mobile devices such as mobile phones, specialized devices like personal digital assistants (PDA). We also applied the method called "mutual accessibility" for discovering communities. We presented the results obtained through our method. It is feasible that our method produced accurate identification of community structure in large complex networks.
Corporate social and Eco-friendly Co₂ emission environment are essential for a firm's and emp... more Corporate social and Eco-friendly Co₂ emission environment are essential for a firm's and employees' health. This Study investigates the impact of Corporate social environment and Co₂ emission environment on Organizational Performance the mediator role of social capital. The study used 260 Pakistan stock exchange-listed firms data from 2011 to 2020 and estimated impact through Regression least square method and GMM. Robust least square test used for validity and sustainability of results. The results of Regression least square and GMM confirmed that the Corporate social environment and environment friendly Co₂ emission have high significant positive impact on Organizational Performance. Social capital role as mediator is highly positive significance that enhances employee’s social, environment Co₂ emission activity and firm outcomes; Indicate corporate social environment, eco-friendly Co₂ emission and social capital have intangible potential Capital of a firm and their signi...
The performance of water as a heat transfer medium in numerous applications is limited by its eff... more The performance of water as a heat transfer medium in numerous applications is limited by its effective thermal conductivity. To improve the thermal conductivity of water, herein, we report the development and thermophysical characterization of novel metal-metal-oxide-carbon-based ternary-hybrid nanoparticles (THNp) GO-TiO2-Ag and rGO-TiO2-Ag. The results indicate that the graphene oxide- and reduced graphene oxide-based ternary-hybrid nanoparticles dispersed in water enhance the base fluid (H2O) thermal conductivity by 66% and 83%, respectively, even at very low concentrations. Mechanisms contributing to this significant enhancement are discussed. The experimental thermal conductivity is plotted against the existing empirical hybrid thermal conductivity correlations. We found that those correlations are not suitable for the metal-metal-oxide-carbon combinations, calling for new thermal conductivity models. Furthermore, the rheological measurements of the nanofluids display non-Newt...
RISUS - Revista de Inovação e Sustentabilidade, Oct 27, 2022
The main reason for this examination is to analyze the position of small financial institutions t... more The main reason for this examination is to analyze the position of small financial institutions that take care of women's independence in Pakistan due to the fact women also are the most vulnerable communities in Pakistan and the arena, too. To address this difficulty, current studies have followed a multidisciplinary method and the improvement of differentiated research. Using a survey questionnaire, information has been accrued from female clients of small financial institutions from might also May 1, 2019, to August 30, 2019. The outcomes of this look revealed that only a few monetary establishments have a crucial position to play in promoting women's independence. With the assist of women's small organizations, offerings provided by means of a small financial group which includes low credit, low financial savings, low coverage, low schooling, and social funding play a first-rate function in promoting women's independence.
Active macro seepages of methane that occur in between the north bank of the Brahmaputra river an... more Active macro seepages of methane that occur in between the north bank of the Brahmaputra river and Himalayan foothill region of Assam Arakan Basin, India, indicate the presence of hydrocarbon accumulation in the subsurface, but the hydrocarbon prospects in this region are not well studied. We carried out an extensive field sampling, which included a total of 58 sediment core collections from an active gas seepage location and nearby areas at a depth of 2–2.5 m. Our sample locations are placed at 1 km intervals laterally. We performed laboratory investigations and mapped near-surface chemical alterations associated with active macro seepages and microseepages. The analysis of geochemical composition of hydrocarbon gases in the sediment indicates both the biogenic and thermogenic origins of seeped hydrocarbons. The stable isotope analysis of methane suggests the presence of thermogenic as well as mixed biogenic-thermogenic gases. The presence of such mixing of gases is caused by the s...
INTERNATIONAL JOURNAL OF DESIGN AND MANUFACTURING TECHNOLOGY, Dec 3, 2014
Cooling by an acousticwave is one of the attractive areas of research in the field of cry coolers... more Cooling by an acousticwave is one of the attractive areas of research in the field of cry coolers and refrigeration. Towards the development of such systems, simulation can be carried out by several methods. We present here the simulation studies of thermo acoustically driven standing wave refrigerator and traveling wave thermoacoustic prime mover for the pulse tube refrigeration using the procedures of Computational Fluid Dynamics (CFD). The CFD analysis is carried out using Ansys Fluent, incorporating the necessary boundary conditions, for different operating and geometric parameters. The study indicates that the working fluid has an influence on the system frequency and on the pressure amplitude. The results obtained by CFD are compared with those obtained using experiments wherever possible and they are in good agreement.
This study presents the rheological behavior of water-based GO-TiO2-Ag and rGO-TiO2-Ag ternary-hy... more This study presents the rheological behavior of water-based GO-TiO2-Ag and rGO-TiO2-Ag ternary-hybrid nanofluids. The impact of nanoparticles’ volumetric concentration and temperature on the rheological properties were studied. All experiments were performed under temperatures ranging from 25 to 50 °C in the solid volume concentration range of 0.5–0.00005%. The data optimization technique was adopted using the Taguchi method. The types of nanomaterials, concentration, temperature, and shear rate were chosen to optimize the viscosity and shear stress. The effect of shear stress, angular sweep, frequency sweep, and damping factor ratio is plotted. The experimental results demonstrated that the rheological properties of the ternary hybrid nanofluid depend on the ternary hybrid nanofluid’s temperature. The viscosity of ternary hybrid nanofluids (THNf) change by 40% for GO-TiO2-Ag and 33% for rGO-TiO2-Ag when temperature and shear rates are increased. All the ternary hybrid nanofluids de...
Handbook of Advanced Ceramics and Composites, 2020
Optical glass and glass ceramic components with angstrom-level surface roughness and nanometer-le... more Optical glass and glass ceramic components with angstrom-level surface roughness and nanometer-level dimensional accuracy are in potential demand for sophisticated optical fabrication. In recent years, aspherical and free-form surfaces are gaining prominence for high performance applications. Moreover, the new optical materials and fabrication process which exhibit superior mechanical properties are being developed to meet the stringent requirements and harsh environment. Fabrication of complex-shaped high optical finish components becomes a significant challenge as conventional finishing techniques are unable to machine aspherical or free-form surfaces precisely. This situation demands few highly advanced and precise finishing processes which ensure stress-free surfaces. Mostly, the optical components are fabricated by shaping or pre-finishing methods followed by final finishing processes. Final finishing processes include more deterministic and flexible polishing techniques that can achieve desired surface finish, figure accuracy and surface integrity to make it suitable for shorter wavelength applications. In this chapter, basic principle, mechanism of various material removal processes, and precision polishing techniques such as magnetorheological fluid-based finishing were discussed and are compared with the convention polishing techniques.
This paper describes the design and implementation of a single axis sun tracking and protection s... more This paper describes the design and implementation of a single axis sun tracking and protection system. This utilizes LDR's and air-flow sensors to make PV cell facing in the direction of maximum irradiation to promote system efficiency and also aligning them parallel to the direction of harsh winds for panel protection. Meanwhile, the algorithm is implemented such that during normal weather, solar tracking occurs and when comes the harsh winds solar tracking is temporarily be replaced by solar protection system. This paper will first highlight and elaborate the concept.
International Journal of Scientific & Technology Research, 2019
Software Process Improvement is generally regarded a key to economic success by increasing the qu... more Software Process Improvement is generally regarded a key to economic success by increasing the quality of software systems, accelerating time-to-market and decreasing development costs. The new software development paradigm is much different from the traditional approach. It is necessary to study and analyze the gap between classical and modern software development methods. The use of agile methods is becoming widespread in the system development industry. Agile methods have several benefits over traditional plan-based methods, in particular their ability to handle projects where requirements are dynamic Organization's varying needs and environments results in context specific adjustments of agile methods. In the present digital transformation world, agility processes, practice and degree of agility need to be assessed. The assessment of agile work is often based on how well the organization complies with a commercial method. In the last few years, a number of agile software development methods have been developed but a detailed evaluation (which is essential) of these methods is not available. In this paper, we survey and compare traditional software development models and agile software models, described their advantages and disadvantages, and discuss the features they inherit. The aim is to identify how gaps between practice and priority can be measured. A detailed study has been conducted to measure the perceptual performance of five Scrum practices with consideration to the prioritization of seven agile aspects. The results shows that the studied agile aspects are considered essential in the organization and that practices in some cases underperform or over perform. This paper presents a detailed comparative analysis of two well-known agile methods, XP and Scrum, based on agility characterization. However, in this study, compliance of practices to strategic priorities is considered.
Previous studies on the utilization of electric arc furnace (e.a.f.) dusts and the recovery of va... more Previous studies on the utilization of electric arc furnace (e.a.f.) dusts and the recovery of valuable metals are based mostly on pyrometallurgical methods. Such methods are expensive to install and operate. In the present study an attempt has been made to recover the main constituents such as iron, lead and zinc of e.a.f. dusts through a hydrometallurgical route by treating the dust with sodium-hydroxide solution. The iron compounds are obtained as a solid residue while lead and zinc remain in solution which is being used for the separation of lead by cementation. Along with this study the physico-chemical properties have been characterised, Lead has been separated from the solution by a technique of cementation in batch and continuous systems using zinc as a precipitant metal. In the batch system the effect of temperature, stirring speed, caustic concentration, on the rate of cementation are investigated. The results confirm that the process is controlled by the counter diffusion...
International Journal of Engineering Research and, 2020
The transmission and reception of information such as the data from a sensor, data in form of ima... more The transmission and reception of information such as the data from a sensor, data in form of images, text, voice and videos on Field Programmable Gate Arrays (FPGAs) over ethernet through a coaxial cable, involves attenuation and distortion of signals at certain speed. Since conventional FPGAs do not have an optical fiber interface port, an external optical interface circuits are needed to establish fiber optic communication links between two conventional FPGA's to have a secured and fast communication link. The main aim of this paper is to present an approach to establish optical fiber communication by employing the standard IEEE 802.3 Ethernet and Optical Sensing circuits that can be implemented on an FPGA. The Ethernet MAC transmitter and Receiver modules are designed in Verilog using Xilinx Vivado and verified for the functionality on Xilinx Nexys 4 board. The Optical Sensing Circuits are designed and simulation is done on Multisim and functionalities are verified. The Optical Driver and the Optical Detector circuits are made to operate in Mega Hertz range for a Fast Ethernet (referred as 100Base-T) that enables transmission of data over 100 Megabits per second on Local Area Network (LAN).
Herein, renewable and uniform nanospheres based on chitosan (CS) and lignosulfonate (LS): (CS@LS)... more Herein, renewable and uniform nanospheres based on chitosan (CS) and lignosulfonate (LS): (CS@LS) were designed for the first time through a simple one-step covalent cross-linking protocol.
Certainly, photovoltaics (PV) is regarded as one of the most reliable and competitive energy prod... more Certainly, photovoltaics (PV) is regarded as one of the most reliable and competitive energy production alternatives due to a massive decline in prices. Coming years are expected to witness PV systems leading the renewable electricity capacity growth by surpassing 550 GW. However, the efficiency of the enormous number of PV modules being produced and installed remains poor due to overheating. PV systems that are cooled using liquid coolants, popularly known as photovoltaic-thermal (PV/T) is a promising solution, but the inherent thermal conductivity of the conventional coolants being used makes it less attractive. Besides the evolution of next-generation PV modules and efficient designs, a breakthrough was made when nanoparticles successfully dispersed in coolants that led to better heat transfer and energy conversion. In recent years, hybrid nanoparticle-based fluids have helped augment heat transfer through PV panels. In this review, we discussed the evolution of PV/T system; difficulties faced in improving thermal and electrical production, and explain how the design modifications and hybrid nanofluids contribute in enhancing the system performance. In terms of the PV/T efficiency, we specifically highlight the role of hybrid nanofluids and the struggles arise from design to operation through 10 big questions and some possible solutions are also suggested to overcome those issues. INDEX TERMS Solar thermal, hybrid nanofluids, channel flow patterns, channel geometry, heat transfer, thermal conductivity.
INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY, 2013
In wireless communication systems reducing bit/frame/symbol error rate is critical. If bit error ... more In wireless communication systems reducing bit/frame/symbol error rate is critical. If bit error rates are high then in wireless communication system our aim is to minimize error by employing various coding methods on the data transferred. Various channel coding for error detection and correction helps the communication system designers to reduce the effects of a noisy data transmission channel. In this paper our focus is to study and analysis of the performance of Reed-Solomon code that is used to encode the data stream in digital communication. The performances were evaluated by applying to different phase sift keying (PSK) modulation scheme in Noisy channel. Reed-Solomon codes are one of the best for correcting burst errors and find wide range of applications in digital communications and data storage. Reed-Solomon codes are good coding technique for error correcting, in which redundant information is added to data so that it can be recovered reliably despite errors in transmissi...
Generally, wind to power conversion is calculated by assuming the quality of wind as measured wit... more Generally, wind to power conversion is calculated by assuming the quality of wind as measured with a Weibull probability distribution at wind speed during power generation. We build on this method by modifying the Weibull distributions to reflect the actual range of wind speeds and wind energy density. This was combined with log law that modifies wind speed based on the height from the ground, to derive the wind power potential at windy sites. The study also provides the levelized cost of renewable energy and hydrogen conversion capacity at the proposed sites. The calculated cost ($/kWh) suggests that the commercial viability is not feasible. We have also electrolyzed the wind-generated electricity to measure the production capacity of renewable hydrogen. We found that all the sites considered are commercially viable for hydrogen production from wind-generated electricity.
Concrete, an integral part of a nuclear power plant (NPP), experiences degradation during their o... more Concrete, an integral part of a nuclear power plant (NPP), experiences degradation during their operational lifetime of the plant. In this review, the major causes of concrete degradation are extensively discussed including mechanisms that are specific to NPPs. The damage mechanism could be chemical or physical. The major causes of chemical degradation include alkali–aggregate reactions, leaching, sulfate attack, bases and acids attack, and carbonation. Physical degradation is a consequence of both environmental and mechanical factors combined. These factors are mainly elevated temperature, radiation, abrasion and erosion, salt crystallization, freeze–thaw distortions, fatigue and vibration. Additionally, steel reinforcements, prestressing steels, liner plates, and structural steel also experience degradation. The prospective areas in the structural components of the NPP where the degradation could occur are mentioned and the effective solutions to the causes of degradation are high...
The wide applicability of acoustics in the life of mankind spread over health, energy, environmen... more The wide applicability of acoustics in the life of mankind spread over health, energy, environment, etc. These acoustic technologies rely on the materials properties with which are made of. However,...
Zenodo (CERN European Organization for Nuclear Research), May 23, 2009
This paper presents the design, fabrication and evaluation of magneto-rheological damper. Semi-ac... more This paper presents the design, fabrication and evaluation of magneto-rheological damper. Semi-active control devices have received significant attention in recent years because they offer the adaptability of active control devices without requiring the associated large power sources. Magneto-Rheological (MR) dampers are semi-active control devices that use MR fluids to produce controllable dampers. They potentially offer highly reliable operation and can be viewed as fail-safe in that they become passive dampers if the control hardware malfunction. The advantage of MR dampers over conventional dampers are that they are simple in construction, compromise between high frequency isolation and natural frequency isolation, they offer semi-active control, use very little power, have very quick response, has few moving parts, have a relax tolerances and direct interfacing with electronics. Magneto-Rheological (MR) fluids are Controllable fluids belonging to the class of active materials that have the unique ability to change dynamic yield stress when acted upon by an electric or magnetic field, while maintaining viscosity relatively constant. This property can be utilized in MR damper where the damping force is changed by changing the rheological properties of the fluid magnetically. MR fluids have a dynamic yield stress over Electro-Rheological fluids (ER) and a broader operational temperature range. The objective of this papert was to study the application of an MR damper to vibration control, design the vibration damper using MR fluids, test and evaluate its performance. In this paper the Rheology and the theory behind MR fluids and their use on vibration control were studied. Then a MR vibration damper suitable for vehicle suspension was designed and fabricated using the MR fluid. The MR damper was tested using a dynamic test rig and the results were obtained in the form of force vs velocity and the force vs displacement plots. The results were encouraging and greatly inspire further research on the topic.
Indian Scientific Journal Of Research In Engineering And Management, Mar 4, 2023
An up-to-date overview of various technologies which are existing to provide home automation from... more An up-to-date overview of various technologies which are existing to provide home automation from different sources is provided. This review covers some evolving technologies in the field of home automation using COB AC LED. A separate review on home automation and COB AC LED is provided. The use of regular LED in various domains is more expensive than the newly developed driverless AC LED, the total cost to build a driverless AC LED and the life span is much higher than the regular LED devices. This paper compared the performance of different ways of home and different ways of controlling the appliances.
Journal of Global Research in Computer Sciences, Mar 6, 2011
Social network gains popularity due to its ease of use, as an application of Web 2.0. The study o... more Social network gains popularity due to its ease of use, as an application of Web 2.0. The study of networks is an active area of research due to its capability of modelling many real world complex systems. One such interesting property to investigate in any typical network is the community structure which is the division of networks into groups. Discovering communities in a social network environment is graph partitioning problem, which subdivides the entire graph into smaller partitions. Graph partitioning is believed as NP -hard problem, due to its complexity to split the number of vertices. We introduced the method of mutual accessibility to find communities in social networking environments. Existing work presents community discovery from blog posts. In this research, we discovered community structures from blogs which are posted by mobile devices such as mobile phones, specialized devices like personal digital assistants (PDA). We also applied the method called "mutual accessibility" for discovering communities. We presented the results obtained through our method. It is feasible that our method produced accurate identification of community structure in large complex networks.
Corporate social and Eco-friendly Co₂ emission environment are essential for a firm's and emp... more Corporate social and Eco-friendly Co₂ emission environment are essential for a firm's and employees' health. This Study investigates the impact of Corporate social environment and Co₂ emission environment on Organizational Performance the mediator role of social capital. The study used 260 Pakistan stock exchange-listed firms data from 2011 to 2020 and estimated impact through Regression least square method and GMM. Robust least square test used for validity and sustainability of results. The results of Regression least square and GMM confirmed that the Corporate social environment and environment friendly Co₂ emission have high significant positive impact on Organizational Performance. Social capital role as mediator is highly positive significance that enhances employee’s social, environment Co₂ emission activity and firm outcomes; Indicate corporate social environment, eco-friendly Co₂ emission and social capital have intangible potential Capital of a firm and their signi...
The performance of water as a heat transfer medium in numerous applications is limited by its eff... more The performance of water as a heat transfer medium in numerous applications is limited by its effective thermal conductivity. To improve the thermal conductivity of water, herein, we report the development and thermophysical characterization of novel metal-metal-oxide-carbon-based ternary-hybrid nanoparticles (THNp) GO-TiO2-Ag and rGO-TiO2-Ag. The results indicate that the graphene oxide- and reduced graphene oxide-based ternary-hybrid nanoparticles dispersed in water enhance the base fluid (H2O) thermal conductivity by 66% and 83%, respectively, even at very low concentrations. Mechanisms contributing to this significant enhancement are discussed. The experimental thermal conductivity is plotted against the existing empirical hybrid thermal conductivity correlations. We found that those correlations are not suitable for the metal-metal-oxide-carbon combinations, calling for new thermal conductivity models. Furthermore, the rheological measurements of the nanofluids display non-Newt...
RISUS - Revista de Inovação e Sustentabilidade, Oct 27, 2022
The main reason for this examination is to analyze the position of small financial institutions t... more The main reason for this examination is to analyze the position of small financial institutions that take care of women's independence in Pakistan due to the fact women also are the most vulnerable communities in Pakistan and the arena, too. To address this difficulty, current studies have followed a multidisciplinary method and the improvement of differentiated research. Using a survey questionnaire, information has been accrued from female clients of small financial institutions from might also May 1, 2019, to August 30, 2019. The outcomes of this look revealed that only a few monetary establishments have a crucial position to play in promoting women's independence. With the assist of women's small organizations, offerings provided by means of a small financial group which includes low credit, low financial savings, low coverage, low schooling, and social funding play a first-rate function in promoting women's independence.
Active macro seepages of methane that occur in between the north bank of the Brahmaputra river an... more Active macro seepages of methane that occur in between the north bank of the Brahmaputra river and Himalayan foothill region of Assam Arakan Basin, India, indicate the presence of hydrocarbon accumulation in the subsurface, but the hydrocarbon prospects in this region are not well studied. We carried out an extensive field sampling, which included a total of 58 sediment core collections from an active gas seepage location and nearby areas at a depth of 2–2.5 m. Our sample locations are placed at 1 km intervals laterally. We performed laboratory investigations and mapped near-surface chemical alterations associated with active macro seepages and microseepages. The analysis of geochemical composition of hydrocarbon gases in the sediment indicates both the biogenic and thermogenic origins of seeped hydrocarbons. The stable isotope analysis of methane suggests the presence of thermogenic as well as mixed biogenic-thermogenic gases. The presence of such mixing of gases is caused by the s...
INTERNATIONAL JOURNAL OF DESIGN AND MANUFACTURING TECHNOLOGY, Dec 3, 2014
Cooling by an acousticwave is one of the attractive areas of research in the field of cry coolers... more Cooling by an acousticwave is one of the attractive areas of research in the field of cry coolers and refrigeration. Towards the development of such systems, simulation can be carried out by several methods. We present here the simulation studies of thermo acoustically driven standing wave refrigerator and traveling wave thermoacoustic prime mover for the pulse tube refrigeration using the procedures of Computational Fluid Dynamics (CFD). The CFD analysis is carried out using Ansys Fluent, incorporating the necessary boundary conditions, for different operating and geometric parameters. The study indicates that the working fluid has an influence on the system frequency and on the pressure amplitude. The results obtained by CFD are compared with those obtained using experiments wherever possible and they are in good agreement.
This study presents the rheological behavior of water-based GO-TiO2-Ag and rGO-TiO2-Ag ternary-hy... more This study presents the rheological behavior of water-based GO-TiO2-Ag and rGO-TiO2-Ag ternary-hybrid nanofluids. The impact of nanoparticles’ volumetric concentration and temperature on the rheological properties were studied. All experiments were performed under temperatures ranging from 25 to 50 °C in the solid volume concentration range of 0.5–0.00005%. The data optimization technique was adopted using the Taguchi method. The types of nanomaterials, concentration, temperature, and shear rate were chosen to optimize the viscosity and shear stress. The effect of shear stress, angular sweep, frequency sweep, and damping factor ratio is plotted. The experimental results demonstrated that the rheological properties of the ternary hybrid nanofluid depend on the ternary hybrid nanofluid’s temperature. The viscosity of ternary hybrid nanofluids (THNf) change by 40% for GO-TiO2-Ag and 33% for rGO-TiO2-Ag when temperature and shear rates are increased. All the ternary hybrid nanofluids de...
Handbook of Advanced Ceramics and Composites, 2020
Optical glass and glass ceramic components with angstrom-level surface roughness and nanometer-le... more Optical glass and glass ceramic components with angstrom-level surface roughness and nanometer-level dimensional accuracy are in potential demand for sophisticated optical fabrication. In recent years, aspherical and free-form surfaces are gaining prominence for high performance applications. Moreover, the new optical materials and fabrication process which exhibit superior mechanical properties are being developed to meet the stringent requirements and harsh environment. Fabrication of complex-shaped high optical finish components becomes a significant challenge as conventional finishing techniques are unable to machine aspherical or free-form surfaces precisely. This situation demands few highly advanced and precise finishing processes which ensure stress-free surfaces. Mostly, the optical components are fabricated by shaping or pre-finishing methods followed by final finishing processes. Final finishing processes include more deterministic and flexible polishing techniques that can achieve desired surface finish, figure accuracy and surface integrity to make it suitable for shorter wavelength applications. In this chapter, basic principle, mechanism of various material removal processes, and precision polishing techniques such as magnetorheological fluid-based finishing were discussed and are compared with the convention polishing techniques.
This paper describes the design and implementation of a single axis sun tracking and protection s... more This paper describes the design and implementation of a single axis sun tracking and protection system. This utilizes LDR's and air-flow sensors to make PV cell facing in the direction of maximum irradiation to promote system efficiency and also aligning them parallel to the direction of harsh winds for panel protection. Meanwhile, the algorithm is implemented such that during normal weather, solar tracking occurs and when comes the harsh winds solar tracking is temporarily be replaced by solar protection system. This paper will first highlight and elaborate the concept.
International Journal of Scientific & Technology Research, 2019
Software Process Improvement is generally regarded a key to economic success by increasing the qu... more Software Process Improvement is generally regarded a key to economic success by increasing the quality of software systems, accelerating time-to-market and decreasing development costs. The new software development paradigm is much different from the traditional approach. It is necessary to study and analyze the gap between classical and modern software development methods. The use of agile methods is becoming widespread in the system development industry. Agile methods have several benefits over traditional plan-based methods, in particular their ability to handle projects where requirements are dynamic Organization's varying needs and environments results in context specific adjustments of agile methods. In the present digital transformation world, agility processes, practice and degree of agility need to be assessed. The assessment of agile work is often based on how well the organization complies with a commercial method. In the last few years, a number of agile software development methods have been developed but a detailed evaluation (which is essential) of these methods is not available. In this paper, we survey and compare traditional software development models and agile software models, described their advantages and disadvantages, and discuss the features they inherit. The aim is to identify how gaps between practice and priority can be measured. A detailed study has been conducted to measure the perceptual performance of five Scrum practices with consideration to the prioritization of seven agile aspects. The results shows that the studied agile aspects are considered essential in the organization and that practices in some cases underperform or over perform. This paper presents a detailed comparative analysis of two well-known agile methods, XP and Scrum, based on agility characterization. However, in this study, compliance of practices to strategic priorities is considered.
Previous studies on the utilization of electric arc furnace (e.a.f.) dusts and the recovery of va... more Previous studies on the utilization of electric arc furnace (e.a.f.) dusts and the recovery of valuable metals are based mostly on pyrometallurgical methods. Such methods are expensive to install and operate. In the present study an attempt has been made to recover the main constituents such as iron, lead and zinc of e.a.f. dusts through a hydrometallurgical route by treating the dust with sodium-hydroxide solution. The iron compounds are obtained as a solid residue while lead and zinc remain in solution which is being used for the separation of lead by cementation. Along with this study the physico-chemical properties have been characterised, Lead has been separated from the solution by a technique of cementation in batch and continuous systems using zinc as a precipitant metal. In the batch system the effect of temperature, stirring speed, caustic concentration, on the rate of cementation are investigated. The results confirm that the process is controlled by the counter diffusion...
International Journal of Engineering Research and, 2020
The transmission and reception of information such as the data from a sensor, data in form of ima... more The transmission and reception of information such as the data from a sensor, data in form of images, text, voice and videos on Field Programmable Gate Arrays (FPGAs) over ethernet through a coaxial cable, involves attenuation and distortion of signals at certain speed. Since conventional FPGAs do not have an optical fiber interface port, an external optical interface circuits are needed to establish fiber optic communication links between two conventional FPGA's to have a secured and fast communication link. The main aim of this paper is to present an approach to establish optical fiber communication by employing the standard IEEE 802.3 Ethernet and Optical Sensing circuits that can be implemented on an FPGA. The Ethernet MAC transmitter and Receiver modules are designed in Verilog using Xilinx Vivado and verified for the functionality on Xilinx Nexys 4 board. The Optical Sensing Circuits are designed and simulation is done on Multisim and functionalities are verified. The Optical Driver and the Optical Detector circuits are made to operate in Mega Hertz range for a Fast Ethernet (referred as 100Base-T) that enables transmission of data over 100 Megabits per second on Local Area Network (LAN).
Herein, renewable and uniform nanospheres based on chitosan (CS) and lignosulfonate (LS): (CS@LS)... more Herein, renewable and uniform nanospheres based on chitosan (CS) and lignosulfonate (LS): (CS@LS) were designed for the first time through a simple one-step covalent cross-linking protocol.
Certainly, photovoltaics (PV) is regarded as one of the most reliable and competitive energy prod... more Certainly, photovoltaics (PV) is regarded as one of the most reliable and competitive energy production alternatives due to a massive decline in prices. Coming years are expected to witness PV systems leading the renewable electricity capacity growth by surpassing 550 GW. However, the efficiency of the enormous number of PV modules being produced and installed remains poor due to overheating. PV systems that are cooled using liquid coolants, popularly known as photovoltaic-thermal (PV/T) is a promising solution, but the inherent thermal conductivity of the conventional coolants being used makes it less attractive. Besides the evolution of next-generation PV modules and efficient designs, a breakthrough was made when nanoparticles successfully dispersed in coolants that led to better heat transfer and energy conversion. In recent years, hybrid nanoparticle-based fluids have helped augment heat transfer through PV panels. In this review, we discussed the evolution of PV/T system; difficulties faced in improving thermal and electrical production, and explain how the design modifications and hybrid nanofluids contribute in enhancing the system performance. In terms of the PV/T efficiency, we specifically highlight the role of hybrid nanofluids and the struggles arise from design to operation through 10 big questions and some possible solutions are also suggested to overcome those issues. INDEX TERMS Solar thermal, hybrid nanofluids, channel flow patterns, channel geometry, heat transfer, thermal conductivity.
INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY, 2013
In wireless communication systems reducing bit/frame/symbol error rate is critical. If bit error ... more In wireless communication systems reducing bit/frame/symbol error rate is critical. If bit error rates are high then in wireless communication system our aim is to minimize error by employing various coding methods on the data transferred. Various channel coding for error detection and correction helps the communication system designers to reduce the effects of a noisy data transmission channel. In this paper our focus is to study and analysis of the performance of Reed-Solomon code that is used to encode the data stream in digital communication. The performances were evaluated by applying to different phase sift keying (PSK) modulation scheme in Noisy channel. Reed-Solomon codes are one of the best for correcting burst errors and find wide range of applications in digital communications and data storage. Reed-Solomon codes are good coding technique for error correcting, in which redundant information is added to data so that it can be recovered reliably despite errors in transmissi...
Generally, wind to power conversion is calculated by assuming the quality of wind as measured wit... more Generally, wind to power conversion is calculated by assuming the quality of wind as measured with a Weibull probability distribution at wind speed during power generation. We build on this method by modifying the Weibull distributions to reflect the actual range of wind speeds and wind energy density. This was combined with log law that modifies wind speed based on the height from the ground, to derive the wind power potential at windy sites. The study also provides the levelized cost of renewable energy and hydrogen conversion capacity at the proposed sites. The calculated cost ($/kWh) suggests that the commercial viability is not feasible. We have also electrolyzed the wind-generated electricity to measure the production capacity of renewable hydrogen. We found that all the sites considered are commercially viable for hydrogen production from wind-generated electricity.
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Papers by Abdul Rasheed