Subrata Roy - Academia.edu (original) (raw)
Papers by Subrata Roy
Symposium - International Astronomical Union, 2002
Journal of Applied Physics, 2003
Microchannel based systems have emerged as a critical design trend in development of precise cont... more Microchannel based systems have emerged as a critical design trend in development of precise control and maneuvering of small devices. In microelectronics, space propulsion and biomedical areas, these systems are especially useful. Nanoscale pores are recently becoming of great interest due to their beneficial drag and heat transfer properties. However it is difficult to predict the flow performance of these microsystems and nanosystems numerically since the standard assumptions of using Navier-Stokes equations break down at micrometer scales, while the computational times of applicable molecular-dynamics codes become exorbitant. A two-dimensional finite-element based microscale flow model is developed to efficiently predict the overall flow characteristics up to the transition regime for reasonably high Knudsen number flow inside microchannels and nanopores. Presented two-dimensional numerical results for Poiseuille flow of a simple fluid through the microchannel are comparable to the numerical and experimental data published in the literature. The nanopore solutions are also validated with presented experimental data.
Proceedings of the 2000 Ieee International Test Conference, Oct 3, 2000
Page 1. Efficient Test Mode Selection & Insertion for RTL-BIST Subrata Roy Gokhan Gun... more Page 1. Efficient Test Mode Selection & Insertion for RTL-BIST Subrata Roy Gokhan Guner Kwang-Ting(Tim) Cheng Lucent Technologies Department of ECE Department of ECE Bell Laboratories University of California University of California ...
Replacement and rehabilitation of corrosion defects in the approximately 400,000 miles of high-pr... more Replacement and rehabilitation of corrosion defects in the approximately 400,000 miles of high-pressure transmission and gathering line pipe result in substantial annual costs to the industry. Repair of dent damage due to third-party construction equipment, the most prevalent type of incident, adds significantly to the cost. A multifaceted program was devised which included the development of a repair analysis model,
ABSTRACT Certain parameters like nozzle geometry, jet impingement angle, fluid properties and noz... more ABSTRACT Certain parameters like nozzle geometry, jet impingement angle, fluid properties and nozzle-to-target plane spacing are critically important in jet impingement heat transfer process. In this paper, the fluid-thermal characteristics of an array of two ...
Proceedings International Test Conference 2000 (IEEE Cat. No.00CH37159), 2000
Inserting test logic at the Register Transfer Level (RTL), instead of at the gate-level, offers m... more Inserting test logic at the Register Transfer Level (RTL), instead of at the gate-level, offers many advantages. It allows the synthesis process to consider both functional and test logic together for optimization for meeting the timing/area/power goals; thus, this avoids an expensive cycle of re-optimization. It is also a necessary step for supporting RTL signoff. In this paper, we present
Mineral Processing and Extractive Metallurgy IMM Transactions section C
The use of electrical and electronic equipment increases consistently. Printed circuit boards, in... more The use of electrical and electronic equipment increases consistently. Printed circuit boards, incorporated in most electrical and electronic equipment, contain valuable metals such as Cu, Ni, Au, Ag, Pd, Fe, Sn and Pb, etc. The circuit boards are rich in metal content and the need for processing these wastes to extract the metals values and remove the non-metallic constituents has been felt all over the world. Eddy current separators (ECS) are increasingly used in waste processing industries. A deeper understanding of the influences of a large number of parameters involved in Eddy Current Separator system is of great help in optimizing the performance of an Eddy Current separator. The present study summarizes the effect of operating variables of crushed PCB waste using ECS. Detailed experimentation has been performed with crushed printed circuit boards according to a Box-Behnken design of experiments to establish the influence of operating variables on the separation performance. T...
42nd AIAA Aerospace Sciences Meeting and Exhibit, 2004
The study of fluid flow through tiny structures is fundamental to any future technologies. Specif... more The study of fluid flow through tiny structures is fundamental to any future technologies. Specifically efficient numerical modeling of subsonic single component microscale flow is the subject. We implement a recently developed two-dimensional hydrodynamic finite element model for ...
The Review of scientific instruments, 2013
The paper describes the design, calibration, and characterization of a thrust stand capable of na... more The paper describes the design, calibration, and characterization of a thrust stand capable of nano-Newton resolution. A low uncertainty calibration method is proposed and demonstrated. A passive eddy current based damper, which is non-contact and vacuum compatible, is employed. Signal analysis techniques are used to perform noise characterization, and potential sources are identified. Calibrated system noise floor suggests thrust measurement resolution of the order of 10 nN is feasible under laboratory conditions. Force measurement from this balance for a standard macroscale dielectric barrier discharge (DBD) plasma actuator is benchmarked with a commercial precision balance of 9.8 μN resolution and is found to be in good agreement. Published results of a microscale DBD plasma actuator force measurement and low pressure characterization of conventional plasma actuators are presented for completeness.
Smart Materials, Structures, and Systems, 2003
ABSTRACT A modified-CVD method was developed to deposit thin films of oxides for device applicati... more ABSTRACT A modified-CVD method was developed to deposit thin films of oxides for device applications. ZnO thin films were deposited on various substrates after optimizing the growth parameters. The quality of the ZnO films was investigated using x-ray diffraction and scanning electron microscopy. The same ZnO film deposited on quartz substrate has been used for sensing hydrogen gas at 400°C.
Symposium - International Astronomical Union, 2002
Journal of Applied Physics, 2003
Microchannel based systems have emerged as a critical design trend in development of precise cont... more Microchannel based systems have emerged as a critical design trend in development of precise control and maneuvering of small devices. In microelectronics, space propulsion and biomedical areas, these systems are especially useful. Nanoscale pores are recently becoming of great interest due to their beneficial drag and heat transfer properties. However it is difficult to predict the flow performance of these microsystems and nanosystems numerically since the standard assumptions of using Navier-Stokes equations break down at micrometer scales, while the computational times of applicable molecular-dynamics codes become exorbitant. A two-dimensional finite-element based microscale flow model is developed to efficiently predict the overall flow characteristics up to the transition regime for reasonably high Knudsen number flow inside microchannels and nanopores. Presented two-dimensional numerical results for Poiseuille flow of a simple fluid through the microchannel are comparable to the numerical and experimental data published in the literature. The nanopore solutions are also validated with presented experimental data.
Proceedings of the 2000 Ieee International Test Conference, Oct 3, 2000
Page 1. Efficient Test Mode Selection & Insertion for RTL-BIST Subrata Roy Gokhan Gun... more Page 1. Efficient Test Mode Selection & Insertion for RTL-BIST Subrata Roy Gokhan Guner Kwang-Ting(Tim) Cheng Lucent Technologies Department of ECE Department of ECE Bell Laboratories University of California University of California ...
Replacement and rehabilitation of corrosion defects in the approximately 400,000 miles of high-pr... more Replacement and rehabilitation of corrosion defects in the approximately 400,000 miles of high-pressure transmission and gathering line pipe result in substantial annual costs to the industry. Repair of dent damage due to third-party construction equipment, the most prevalent type of incident, adds significantly to the cost. A multifaceted program was devised which included the development of a repair analysis model,
ABSTRACT Certain parameters like nozzle geometry, jet impingement angle, fluid properties and noz... more ABSTRACT Certain parameters like nozzle geometry, jet impingement angle, fluid properties and nozzle-to-target plane spacing are critically important in jet impingement heat transfer process. In this paper, the fluid-thermal characteristics of an array of two ...
Proceedings International Test Conference 2000 (IEEE Cat. No.00CH37159), 2000
Inserting test logic at the Register Transfer Level (RTL), instead of at the gate-level, offers m... more Inserting test logic at the Register Transfer Level (RTL), instead of at the gate-level, offers many advantages. It allows the synthesis process to consider both functional and test logic together for optimization for meeting the timing/area/power goals; thus, this avoids an expensive cycle of re-optimization. It is also a necessary step for supporting RTL signoff. In this paper, we present
Mineral Processing and Extractive Metallurgy IMM Transactions section C
The use of electrical and electronic equipment increases consistently. Printed circuit boards, in... more The use of electrical and electronic equipment increases consistently. Printed circuit boards, incorporated in most electrical and electronic equipment, contain valuable metals such as Cu, Ni, Au, Ag, Pd, Fe, Sn and Pb, etc. The circuit boards are rich in metal content and the need for processing these wastes to extract the metals values and remove the non-metallic constituents has been felt all over the world. Eddy current separators (ECS) are increasingly used in waste processing industries. A deeper understanding of the influences of a large number of parameters involved in Eddy Current Separator system is of great help in optimizing the performance of an Eddy Current separator. The present study summarizes the effect of operating variables of crushed PCB waste using ECS. Detailed experimentation has been performed with crushed printed circuit boards according to a Box-Behnken design of experiments to establish the influence of operating variables on the separation performance. T...
42nd AIAA Aerospace Sciences Meeting and Exhibit, 2004
The study of fluid flow through tiny structures is fundamental to any future technologies. Specif... more The study of fluid flow through tiny structures is fundamental to any future technologies. Specifically efficient numerical modeling of subsonic single component microscale flow is the subject. We implement a recently developed two-dimensional hydrodynamic finite element model for ...
The Review of scientific instruments, 2013
The paper describes the design, calibration, and characterization of a thrust stand capable of na... more The paper describes the design, calibration, and characterization of a thrust stand capable of nano-Newton resolution. A low uncertainty calibration method is proposed and demonstrated. A passive eddy current based damper, which is non-contact and vacuum compatible, is employed. Signal analysis techniques are used to perform noise characterization, and potential sources are identified. Calibrated system noise floor suggests thrust measurement resolution of the order of 10 nN is feasible under laboratory conditions. Force measurement from this balance for a standard macroscale dielectric barrier discharge (DBD) plasma actuator is benchmarked with a commercial precision balance of 9.8 μN resolution and is found to be in good agreement. Published results of a microscale DBD plasma actuator force measurement and low pressure characterization of conventional plasma actuators are presented for completeness.
Smart Materials, Structures, and Systems, 2003
ABSTRACT A modified-CVD method was developed to deposit thin films of oxides for device applicati... more ABSTRACT A modified-CVD method was developed to deposit thin films of oxides for device applications. ZnO thin films were deposited on various substrates after optimizing the growth parameters. The quality of the ZnO films was investigated using x-ray diffraction and scanning electron microscopy. The same ZnO film deposited on quartz substrate has been used for sensing hydrogen gas at 400°C.