Spacing control is important topics of research as increasing number of vehicle are automatically... more Spacing control is important topics of research as increasing number of vehicle are automatically controlled in land, space and under water. Spacing control has importance as it helps in safety of passengers and also saves time and fuel. It has application in many fields like aircraft flight formation vehicle platooning, spacecraft, etc. A platoon is group of vehicles travelling with a leader which is followed by the others. Information of the leader is very important in case of platoon to be safe. Vehicles are equipped with wireless communication which is used in sending and receiving information from the other vehicle and specially leader information. These communication systems are not always prefect, sometime or frequently it gets affected by environmental factors and is not able to send and receive information. The need of robust control law to minimize the distance between vehicles and that remains robust in uncertain conditions is important. In this research Switched Static Output Feedback Stabilization with LMI approach has been used. This method has advantages over earlier method that has limitation over switching sequence. Using SOF method gives us a simple control methodology that doesn't need state information and LMI method is reliable in finding stability condition. It results in a control method that will stabilize the system in any arbitrary switching. System will attain string stability as it will ensure that error between vehicles doesn't increases as we go down the platoon .
ASPET 2023 Annual Meeting Abstract - Cellular and Molecular Pharmacology
Endocytosis of G protein-coupled receptors (GPCRs) via clathrin-coated pits (CCPs) is crucial for... more Endocytosis of G protein-coupled receptors (GPCRs) via clathrin-coated pits (CCPs) is crucial for receptor desensitization and signaling. The core protein machinery that mediate CCP initiation, maturation, and scission have been heavily studied. Although this core protein machinery is broadly distributed and shared between all CCPs, these structures are initiated at spatially non-random sites on the membrane and are restricted to specialized regions in some cell types. Whether the physical properties of the membrane itself contribute to this specialization is not well understood. Here, we use high resolution multichannel total internal reflection fluorescence microscopy (TIR-FM) to measure lipid order in the plasma membrane using a dual channel ratiometric fluorescence readout from a solvatochromic pyrene-based probe. Lipid order imaging in CCP clusters showed that CCPs represent membrane domains of a lower order relative to the rest of the plasma membrane. The lipid order in endocytic clusters exhibited time-resolved changes during CCP maturation. The prototypical GPCR, b 2 -adrenergic receptor (b2AR) clusters into a subset of CCPs in response to activation by its agonist isoproterenol. Interestingly, b2AR-containing CCPs exhibited higher lipid order relative to CCPs that did not contain the receptor. However, such a difference was not observed in case of another class A GPCR, the delta opioid receptor (DOR), and the constitutively internalizing cargo, transferrin. b2AR, unlike DOR, has been shown to extend CCP lifetimes and receptor residence times on the membrane via a C-terminal PDZ ligand that links the receptor to the actin cytoskeleton. We show here that the difference in lipid order between b2AR-containing CCPs and CCPs that do not contain b2AR was abrogated upon disruption of the b2AR C-terminal PDZ ligand. Overall, our results show that CCPs represent specialized membrane domains with a distinct lipid order, and that lipid order is an important determinant of cargo-specificity in GPCR endocytosis.
We present an O(nlogn) algorithm to compile a switch statement into jump tables. To generate jump... more We present an O(nlogn) algorithm to compile a switch statement into jump tables. To generate jump tables that can be efficiently predicted by current hardware branch predictors, we added an upper bound on the number of entries for each table. This modification of the previously best known algorithm reduces the complexity from O(n 2 ) to O(nlogn).
Communications Faculty Of Science University of Ankara Series A1Mathematics and Statistics
In this paper we impose distinct restrictions on the moduli of the zeros of p(z)=n∑v=0avzvp(z)=∑v... more In this paper we impose distinct restrictions on the moduli of the zeros of p(z)=n∑v=0avzvp(z)=∑v=0navzv and investigate the dependence of ∥p(Rz)−p(σz)∥‖p(Rz)−p(σz)‖, R>σ≥1R>σ≥1 on MαMα and Mα+πMα+π, where Mα=max1≤k≤n|p(ei(α+2kπ)/n)|Mα=max1≤k≤n|p(ei(α+2kπ)/n)| and on certain coefficients of p(z)p(z). This paper comprises several results, which in particular yields some classical polynomial inequalities as special cases. Moreover, the problem of estimating p(1−wn)p(1−wn), $0<w\leq$ given $p(1)=0$ is considered.
In a recent contribution, Kumar, Bourdin, Francfort, and Lopez-Pamies (J. Mech. Phys. Solids 142:... more In a recent contribution, Kumar, Bourdin, Francfort, and Lopez-Pamies (J. Mech. Phys. Solids 142:104027, 2020) have introduced a comprehensive macroscopic phase-field theory for the nucleation and propagation of fracture in linear elastic brittle materials under arbitrary quasistatic loading conditions. The theory can be viewed as a natural generalization of the phase-field approximation of the variational theory of brittle fracture of Francfort and Marigo (J. Mech. Phys. Solids 46:1319-1342, 1998) to account for the material strength at large. This is accomplished by the addition of an external driving force -which physically represents the macroscopic manifestation of the presence of inherent microscopic defects in the material -in the equation governing the evolution of the phase field. The main purpose of this paper is to continue providing validation results for the theory by confronting its predictions with direct measurements from three representative types of experimentally
Amid the previous existences a while, fuzzy controller depends on fuzzy logic included manages in... more Amid the previous existences a while, fuzzy controller depends on fuzzy logic included manages in a sure level of ideas can't be communicated as the " genuine" or "false" however a bit "in part genuine" are most dynamic and productive ranges for examination arranged applications particularly in the domain of mechanical procedure of data yield relations. The compensator is proposed for use with every individual distributed span (DS) framework in the smaller scale matrix, and comprises of two four - leg inverters (an arrangement and a shunt), ideally controlled to accomplish an improvement of both the nature of force inside of the miniaturized scale network and the nature of streams existing between the small scale lattice and usage framework. The reason for a four-leg voltage-source inverter (4LVSI) allow the pay of current consonant fixings, incorporating unequal current created in single-stage nonlinear burdens. An exact straightforward numerical m...
In this paper, we build a hybrid personalized music recommendation system that takes into account... more In this paper, we build a hybrid personalized music recommendation system that takes into account the user's previous listening history, real-time body parameters such as heart rate and interest of similar users. We build a unique unsupervised hierarchical model that combines all these attributes and computes the best song recommendation to the user.
Protein-minimization is an attractive approach for designing vaccines against rapidly evolving pa... more Protein-minimization is an attractive approach for designing vaccines against rapidly evolving pathogens such as HIV-1 since it can help in focussing the immune response towards conserved conformational epitopes present on complex targets. The outer domain (OD) of HIV-1 gp120 contains epitopes for a large number of neutralizing antibodies and therefore is a primary target for structure-based vaccine design. We have previously designed a bacterially expressed outer domain immunogen (OD) that bound CD4 binding site (CD4bs) ligands with 3-12µM affinity and elicited a modest neutralizing antibody response in rabbits. In this study, we have optimized OD using consensus sequence design, cyclic permutation and structure-guided mutations to generate a number of variants with improved yields, biophysical properties, stabilities and affinities (KD of 10-50 nM) for various CD4bs targeting, broadly neutralizing antibodies, including the germline reverted version of the broadly neutralizing anti...
The gp120 subunit of HIV-1 envelope (Env) protein is heavily glycosylated at approximately 25 gly... more The gp120 subunit of HIV-1 envelope (Env) protein is heavily glycosylated at approximately 25 glycosylation sites, of which ~7-8 are located in the V1/V2 and V3 variable loops and the others in the remaining core gp120 region. Glycans partially shield Env from recognition by the host immune system and also are believed to be indispensable for proper folding of gp120 and for viral infectivity. Previous attempts to alter glycosylation sites in Env typically involved mutating the glycosylated asparagine residues to structurally similar glutamines or to alanines. Here, we confirmed that such mutations at multiple glycosylation sites greatly diminish viral infectivity and result in significantly reduced binding to both neutralizing and non-neutralizing antibodies. Therefore, using an alternative approach, we combined evolutionary information with structure-guided design and yeast surface display to produce properly cleaved HIV-1 Env variants that lack all 15 core gp120 glycans, yet retai...
This Note lays out the specialization of the two-potential constitutive framework -also known as ... more This Note lays out the specialization of the two-potential constitutive framework -also known as the "generalized standard materials" framework -to rubber viscoelasticity. Inter alia, it is shown that a number of popular rubber viscoelasticity formulations, introduced over the years following different approaches, are special cases of this framework. As a first application of practical relevance, the framework is utilized to put forth a new objective and thermodynamically consistent rubber viscoelastic model for incompressible isotropic elastomers. The model accounts for the non-Gaussian elasticity of elastomers, as well as for the deformation-enhanced shear thinning of their viscous dissipation governed by reptation dynamics. The descriptive and predictive capabilities of the model are illustrated via comparisons with experimental data available from the literature for two commercially significant elastomers.
The current paper presents a comprehensive finite element analysis on stress concentration in ort... more The current paper presents a comprehensive finite element analysis on stress concentration in orthotropic laminates. This research investigates the Stress Concentration Factor (SCF) in isotropic and orthotropic plates due to presence of a central cutout with respect to ply orientation angle (θ). The numerical simulations are carried out by using an 8 node shell element in ANSYS APDL environment. It is established from the simulations that the SCF is dependent upon the orientation the fibers. For orthotropic laminates, SCF depends on material properties. It increases with increase in E y /E x ratio and decreases with increase in μ xy .
2009 59th Electronic Components and Technology Conference, 2009
Developments of ultra fine pitch and high density solder microbumps and assembly process for low ... more Developments of ultra fine pitch and high density solder microbumps and assembly process for low cost 3D stacking technologies are discussed in this paper. The solder microbumps developed in this work consist of Cu and Sn, which are electroplated in sequential with total thickness of 10µm; The under bump metallurgy (UBM) pads used here is electroless plated nickel and immersion gold (ENIG) with thickness of 2µm. Accordingly, joining of the two Si chips can be conducted by joining CuSn solder microbumps to ENIG UBM pads or CuSn solder microbumps to CuSn solder microbumps. The first joining can only be done with chip to chip assembly whereas the second joining has the potential for chip to wafer assembly. Assembly of the Si chips is conducted with the FC150 flip chip bonder at different temperatures, times, and pressures and the optimized bonding conditions are obtained. After assembly, underfill process is carried out to fill the gap and a void free underfilling is achieved using an underfill material with fine filler size.
International Journal of Heat and Mass Transfer, 2014
This paper presents detailed numerical simulations predicting the effective thermal conductivity ... more This paper presents detailed numerical simulations predicting the effective thermal conductivity of spherical monodisperse and polydisperse core-shell particles ordered or randomly distributed in a continuous matrix. First, the effective thermal conductivity of this three-component composite material was found to be independent of the capsule spatial distribution and size distribution. In fact, the study established that the effective thermal conductivity depended only on the core and shell volume fractions and on the core, shell, and matrix thermal conductivities. Second, the effective medium approximation reported by Felske (2004) [21] was in very good agreement with numerical predictions for any arbitrary combination of the above-mentioned parameters. These results can be used to design energy efficient composites, such as microencapsulated phase change materials in concrete and/or insulation materials for energy efficient buildings.
We propose a novel approach for credit card fraud detection, which combines evidences from curren... more We propose a novel approach for credit card fraud detection, which combines evidences from current as well as past behavior. The fraud detection system (FDS) consists of four components, namely, rule-based filter, Dempster-Shafer adder, transaction history database and Bayesian learner. In the rule-based component, we determine the suspicion level of each incoming transaction based on the extent of its deviation from good pattern. Dempster-Shafer's theory is used to combine multiple such evidences and an initial belief is computed. The transaction is classified as normal, abnormal or suspicious depending on this initial belief. Once a transaction is found to be suspicious, belief is further strengthened or weakened according to its similarity with fraudulent or genuine transaction history using Bayesian learning. Extensive simulation with stochastic models shows that fusion of different evidences has a very high positive impact on the performance of a credit card fraud detection system as compared to other methods.
Two arbuscular mycorrhizal fungi, Glomus mosseae and Acaulospora laevis either alone or in combin... more Two arbuscular mycorrhizal fungi, Glomus mosseae and Acaulospora laevis either alone or in combination with Trichoderma viride showed the dependence of Rauwolfia serpentina on endomycorrhizal fungi. After 60 days, G. mosseae singly or in combination with Trichoderma viride showed enhanced height increment compared to control plants. Maximum phosphorus content was shown by plants treated with G. mosseae plus T. viride (0.444 ± 2.62) in roots and (0.437 ± 4.71) in shoots. Phosphorus content in roots was more than that in shoots. Chlorophyll content and stomatal conductivity also showed similar trend.
AIAA 1st Intelligent Systems Technical Conference, 2004
To effectively accommodate safety critical faults in-flight it is necessary to rapidly detect the... more To effectively accommodate safety critical faults in-flight it is necessary to rapidly detect them and to have a means to accommodate the fault. We present results on model-based fault detection using sensor residuals from an extended Kalman filter with an embedded real-time engine model to characterize un-faulted behavior over the flight envelope. Thereafter, we present an approach for online fault accommodation via optimal changes in a set of suitable adjustments in the existing FADEC control logic. These optimal adjustments are obtained through off-line optimization for optimal recovery of stall margins and thrust and interpolated online for the existing flight conditions. We present results of the fault detection & accommodation applied to a high-bypass commercial aircraft engine over the flight envelope.
Institute for Plasma Research (IPR) is developing Spherical Tokamak (ST) related technologies to ... more Institute for Plasma Research (IPR) is developing Spherical Tokamak (ST) related technologies to realize a low aspect ratio compact device for plasma experiments. Center Stack is one of the critical components in ST which requires R&D to design, manufacture and assemble in a limited space within required tolerances. A Prototype Center Stack (PCS) is being developed based on reference ST parameters with major radius 0.28 m and minor radius 0.16 m for magnetic field 0.1 T. The main objective of PCS is to design and check its manufacturing feasibility to achieve required tolerances at component and assembly level and maintaining overall accuracy. The PCS assembly consists of two sets of coils, namely Toroidal Field (TF) coils and Ohmic (OH) coil made of Electrolytic Tough Pitch (ETP) Copper. It consists of 6 number of TF coils, with 3 turns per coil, all connected in series. The OH coil has two parallel layers, with 143 turns per layer. The SS 304 support structure consists of tension cylinder and Center Stack Casing (CSC) which are mounted on a pedestal support. Two different capacitor bank based power supplies are considered for TF and OH coils with a maximum operating current of 8.5 kA and 10 kA respectively. This paper discusses the conceptual design, engineering analysis including thermal, electromagnetic and structural analysis using ANSYS Mechanical, Multiphysics and Maxwell modules.
Spacing control is important topics of research as increasing number of vehicle are automatically... more Spacing control is important topics of research as increasing number of vehicle are automatically controlled in land, space and under water. Spacing control has importance as it helps in safety of passengers and also saves time and fuel. It has application in many fields like aircraft flight formation vehicle platooning, spacecraft, etc. A platoon is group of vehicles travelling with a leader which is followed by the others. Information of the leader is very important in case of platoon to be safe. Vehicles are equipped with wireless communication which is used in sending and receiving information from the other vehicle and specially leader information. These communication systems are not always prefect, sometime or frequently it gets affected by environmental factors and is not able to send and receive information. The need of robust control law to minimize the distance between vehicles and that remains robust in uncertain conditions is important. In this research Switched Static Output Feedback Stabilization with LMI approach has been used. This method has advantages over earlier method that has limitation over switching sequence. Using SOF method gives us a simple control methodology that doesn't need state information and LMI method is reliable in finding stability condition. It results in a control method that will stabilize the system in any arbitrary switching. System will attain string stability as it will ensure that error between vehicles doesn't increases as we go down the platoon .
ASPET 2023 Annual Meeting Abstract - Cellular and Molecular Pharmacology
Endocytosis of G protein-coupled receptors (GPCRs) via clathrin-coated pits (CCPs) is crucial for... more Endocytosis of G protein-coupled receptors (GPCRs) via clathrin-coated pits (CCPs) is crucial for receptor desensitization and signaling. The core protein machinery that mediate CCP initiation, maturation, and scission have been heavily studied. Although this core protein machinery is broadly distributed and shared between all CCPs, these structures are initiated at spatially non-random sites on the membrane and are restricted to specialized regions in some cell types. Whether the physical properties of the membrane itself contribute to this specialization is not well understood. Here, we use high resolution multichannel total internal reflection fluorescence microscopy (TIR-FM) to measure lipid order in the plasma membrane using a dual channel ratiometric fluorescence readout from a solvatochromic pyrene-based probe. Lipid order imaging in CCP clusters showed that CCPs represent membrane domains of a lower order relative to the rest of the plasma membrane. The lipid order in endocytic clusters exhibited time-resolved changes during CCP maturation. The prototypical GPCR, b 2 -adrenergic receptor (b2AR) clusters into a subset of CCPs in response to activation by its agonist isoproterenol. Interestingly, b2AR-containing CCPs exhibited higher lipid order relative to CCPs that did not contain the receptor. However, such a difference was not observed in case of another class A GPCR, the delta opioid receptor (DOR), and the constitutively internalizing cargo, transferrin. b2AR, unlike DOR, has been shown to extend CCP lifetimes and receptor residence times on the membrane via a C-terminal PDZ ligand that links the receptor to the actin cytoskeleton. We show here that the difference in lipid order between b2AR-containing CCPs and CCPs that do not contain b2AR was abrogated upon disruption of the b2AR C-terminal PDZ ligand. Overall, our results show that CCPs represent specialized membrane domains with a distinct lipid order, and that lipid order is an important determinant of cargo-specificity in GPCR endocytosis.
We present an O(nlogn) algorithm to compile a switch statement into jump tables. To generate jump... more We present an O(nlogn) algorithm to compile a switch statement into jump tables. To generate jump tables that can be efficiently predicted by current hardware branch predictors, we added an upper bound on the number of entries for each table. This modification of the previously best known algorithm reduces the complexity from O(n 2 ) to O(nlogn).
Communications Faculty Of Science University of Ankara Series A1Mathematics and Statistics
In this paper we impose distinct restrictions on the moduli of the zeros of p(z)=n∑v=0avzvp(z)=∑v... more In this paper we impose distinct restrictions on the moduli of the zeros of p(z)=n∑v=0avzvp(z)=∑v=0navzv and investigate the dependence of ∥p(Rz)−p(σz)∥‖p(Rz)−p(σz)‖, R>σ≥1R>σ≥1 on MαMα and Mα+πMα+π, where Mα=max1≤k≤n|p(ei(α+2kπ)/n)|Mα=max1≤k≤n|p(ei(α+2kπ)/n)| and on certain coefficients of p(z)p(z). This paper comprises several results, which in particular yields some classical polynomial inequalities as special cases. Moreover, the problem of estimating p(1−wn)p(1−wn), $0<w\leq$ given $p(1)=0$ is considered.
In a recent contribution, Kumar, Bourdin, Francfort, and Lopez-Pamies (J. Mech. Phys. Solids 142:... more In a recent contribution, Kumar, Bourdin, Francfort, and Lopez-Pamies (J. Mech. Phys. Solids 142:104027, 2020) have introduced a comprehensive macroscopic phase-field theory for the nucleation and propagation of fracture in linear elastic brittle materials under arbitrary quasistatic loading conditions. The theory can be viewed as a natural generalization of the phase-field approximation of the variational theory of brittle fracture of Francfort and Marigo (J. Mech. Phys. Solids 46:1319-1342, 1998) to account for the material strength at large. This is accomplished by the addition of an external driving force -which physically represents the macroscopic manifestation of the presence of inherent microscopic defects in the material -in the equation governing the evolution of the phase field. The main purpose of this paper is to continue providing validation results for the theory by confronting its predictions with direct measurements from three representative types of experimentally
Amid the previous existences a while, fuzzy controller depends on fuzzy logic included manages in... more Amid the previous existences a while, fuzzy controller depends on fuzzy logic included manages in a sure level of ideas can't be communicated as the " genuine" or "false" however a bit "in part genuine" are most dynamic and productive ranges for examination arranged applications particularly in the domain of mechanical procedure of data yield relations. The compensator is proposed for use with every individual distributed span (DS) framework in the smaller scale matrix, and comprises of two four - leg inverters (an arrangement and a shunt), ideally controlled to accomplish an improvement of both the nature of force inside of the miniaturized scale network and the nature of streams existing between the small scale lattice and usage framework. The reason for a four-leg voltage-source inverter (4LVSI) allow the pay of current consonant fixings, incorporating unequal current created in single-stage nonlinear burdens. An exact straightforward numerical m...
In this paper, we build a hybrid personalized music recommendation system that takes into account... more In this paper, we build a hybrid personalized music recommendation system that takes into account the user's previous listening history, real-time body parameters such as heart rate and interest of similar users. We build a unique unsupervised hierarchical model that combines all these attributes and computes the best song recommendation to the user.
Protein-minimization is an attractive approach for designing vaccines against rapidly evolving pa... more Protein-minimization is an attractive approach for designing vaccines against rapidly evolving pathogens such as HIV-1 since it can help in focussing the immune response towards conserved conformational epitopes present on complex targets. The outer domain (OD) of HIV-1 gp120 contains epitopes for a large number of neutralizing antibodies and therefore is a primary target for structure-based vaccine design. We have previously designed a bacterially expressed outer domain immunogen (OD) that bound CD4 binding site (CD4bs) ligands with 3-12µM affinity and elicited a modest neutralizing antibody response in rabbits. In this study, we have optimized OD using consensus sequence design, cyclic permutation and structure-guided mutations to generate a number of variants with improved yields, biophysical properties, stabilities and affinities (KD of 10-50 nM) for various CD4bs targeting, broadly neutralizing antibodies, including the germline reverted version of the broadly neutralizing anti...
The gp120 subunit of HIV-1 envelope (Env) protein is heavily glycosylated at approximately 25 gly... more The gp120 subunit of HIV-1 envelope (Env) protein is heavily glycosylated at approximately 25 glycosylation sites, of which ~7-8 are located in the V1/V2 and V3 variable loops and the others in the remaining core gp120 region. Glycans partially shield Env from recognition by the host immune system and also are believed to be indispensable for proper folding of gp120 and for viral infectivity. Previous attempts to alter glycosylation sites in Env typically involved mutating the glycosylated asparagine residues to structurally similar glutamines or to alanines. Here, we confirmed that such mutations at multiple glycosylation sites greatly diminish viral infectivity and result in significantly reduced binding to both neutralizing and non-neutralizing antibodies. Therefore, using an alternative approach, we combined evolutionary information with structure-guided design and yeast surface display to produce properly cleaved HIV-1 Env variants that lack all 15 core gp120 glycans, yet retai...
This Note lays out the specialization of the two-potential constitutive framework -also known as ... more This Note lays out the specialization of the two-potential constitutive framework -also known as the "generalized standard materials" framework -to rubber viscoelasticity. Inter alia, it is shown that a number of popular rubber viscoelasticity formulations, introduced over the years following different approaches, are special cases of this framework. As a first application of practical relevance, the framework is utilized to put forth a new objective and thermodynamically consistent rubber viscoelastic model for incompressible isotropic elastomers. The model accounts for the non-Gaussian elasticity of elastomers, as well as for the deformation-enhanced shear thinning of their viscous dissipation governed by reptation dynamics. The descriptive and predictive capabilities of the model are illustrated via comparisons with experimental data available from the literature for two commercially significant elastomers.
The current paper presents a comprehensive finite element analysis on stress concentration in ort... more The current paper presents a comprehensive finite element analysis on stress concentration in orthotropic laminates. This research investigates the Stress Concentration Factor (SCF) in isotropic and orthotropic plates due to presence of a central cutout with respect to ply orientation angle (θ). The numerical simulations are carried out by using an 8 node shell element in ANSYS APDL environment. It is established from the simulations that the SCF is dependent upon the orientation the fibers. For orthotropic laminates, SCF depends on material properties. It increases with increase in E y /E x ratio and decreases with increase in μ xy .
2009 59th Electronic Components and Technology Conference, 2009
Developments of ultra fine pitch and high density solder microbumps and assembly process for low ... more Developments of ultra fine pitch and high density solder microbumps and assembly process for low cost 3D stacking technologies are discussed in this paper. The solder microbumps developed in this work consist of Cu and Sn, which are electroplated in sequential with total thickness of 10µm; The under bump metallurgy (UBM) pads used here is electroless plated nickel and immersion gold (ENIG) with thickness of 2µm. Accordingly, joining of the two Si chips can be conducted by joining CuSn solder microbumps to ENIG UBM pads or CuSn solder microbumps to CuSn solder microbumps. The first joining can only be done with chip to chip assembly whereas the second joining has the potential for chip to wafer assembly. Assembly of the Si chips is conducted with the FC150 flip chip bonder at different temperatures, times, and pressures and the optimized bonding conditions are obtained. After assembly, underfill process is carried out to fill the gap and a void free underfilling is achieved using an underfill material with fine filler size.
International Journal of Heat and Mass Transfer, 2014
This paper presents detailed numerical simulations predicting the effective thermal conductivity ... more This paper presents detailed numerical simulations predicting the effective thermal conductivity of spherical monodisperse and polydisperse core-shell particles ordered or randomly distributed in a continuous matrix. First, the effective thermal conductivity of this three-component composite material was found to be independent of the capsule spatial distribution and size distribution. In fact, the study established that the effective thermal conductivity depended only on the core and shell volume fractions and on the core, shell, and matrix thermal conductivities. Second, the effective medium approximation reported by Felske (2004) [21] was in very good agreement with numerical predictions for any arbitrary combination of the above-mentioned parameters. These results can be used to design energy efficient composites, such as microencapsulated phase change materials in concrete and/or insulation materials for energy efficient buildings.
We propose a novel approach for credit card fraud detection, which combines evidences from curren... more We propose a novel approach for credit card fraud detection, which combines evidences from current as well as past behavior. The fraud detection system (FDS) consists of four components, namely, rule-based filter, Dempster-Shafer adder, transaction history database and Bayesian learner. In the rule-based component, we determine the suspicion level of each incoming transaction based on the extent of its deviation from good pattern. Dempster-Shafer's theory is used to combine multiple such evidences and an initial belief is computed. The transaction is classified as normal, abnormal or suspicious depending on this initial belief. Once a transaction is found to be suspicious, belief is further strengthened or weakened according to its similarity with fraudulent or genuine transaction history using Bayesian learning. Extensive simulation with stochastic models shows that fusion of different evidences has a very high positive impact on the performance of a credit card fraud detection system as compared to other methods.
Two arbuscular mycorrhizal fungi, Glomus mosseae and Acaulospora laevis either alone or in combin... more Two arbuscular mycorrhizal fungi, Glomus mosseae and Acaulospora laevis either alone or in combination with Trichoderma viride showed the dependence of Rauwolfia serpentina on endomycorrhizal fungi. After 60 days, G. mosseae singly or in combination with Trichoderma viride showed enhanced height increment compared to control plants. Maximum phosphorus content was shown by plants treated with G. mosseae plus T. viride (0.444 ± 2.62) in roots and (0.437 ± 4.71) in shoots. Phosphorus content in roots was more than that in shoots. Chlorophyll content and stomatal conductivity also showed similar trend.
AIAA 1st Intelligent Systems Technical Conference, 2004
To effectively accommodate safety critical faults in-flight it is necessary to rapidly detect the... more To effectively accommodate safety critical faults in-flight it is necessary to rapidly detect them and to have a means to accommodate the fault. We present results on model-based fault detection using sensor residuals from an extended Kalman filter with an embedded real-time engine model to characterize un-faulted behavior over the flight envelope. Thereafter, we present an approach for online fault accommodation via optimal changes in a set of suitable adjustments in the existing FADEC control logic. These optimal adjustments are obtained through off-line optimization for optimal recovery of stall margins and thrust and interpolated online for the existing flight conditions. We present results of the fault detection & accommodation applied to a high-bypass commercial aircraft engine over the flight envelope.
Institute for Plasma Research (IPR) is developing Spherical Tokamak (ST) related technologies to ... more Institute for Plasma Research (IPR) is developing Spherical Tokamak (ST) related technologies to realize a low aspect ratio compact device for plasma experiments. Center Stack is one of the critical components in ST which requires R&D to design, manufacture and assemble in a limited space within required tolerances. A Prototype Center Stack (PCS) is being developed based on reference ST parameters with major radius 0.28 m and minor radius 0.16 m for magnetic field 0.1 T. The main objective of PCS is to design and check its manufacturing feasibility to achieve required tolerances at component and assembly level and maintaining overall accuracy. The PCS assembly consists of two sets of coils, namely Toroidal Field (TF) coils and Ohmic (OH) coil made of Electrolytic Tough Pitch (ETP) Copper. It consists of 6 number of TF coils, with 3 turns per coil, all connected in series. The OH coil has two parallel layers, with 143 turns per layer. The SS 304 support structure consists of tension cylinder and Center Stack Casing (CSC) which are mounted on a pedestal support. Two different capacitor bank based power supplies are considered for TF and OH coils with a maximum operating current of 8.5 kA and 10 kA respectively. This paper discusses the conceptual design, engineering analysis including thermal, electromagnetic and structural analysis using ANSYS Mechanical, Multiphysics and Maxwell modules.
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Papers by aditya kumar