The Experts below are selected from a list of 23616 Experts worldwide ranked by ideXlab platform
Hideo Kasami - One of the best experts on this subject based on the ideXlab platform.
-
bonding wire Loop antenna in standard ball grid array package for 60 ghz short range wireless communication
IEEE Transactions on Antennas and Propagation, 2013Co-Authors: Yukako Tsutsumi, Hiroki Shoki, Takayoshi Ito, Koh Hashimoto, Shuichi Obayashi, Hideo KasamiAbstract:High-speed short-range wireless communication systems are expected to utilize the 60-GHz band. This paper presents a bonding wire Loop antenna in a standard ball grid array (BGA) package for 60-GHz short-range wireless communication. The proposed antenna has a Loop Shape and consists of two bonding wires connecting to a complementary metal–oxide–semiconductor (CMOS) chip and a metal plate on an interposer in a BGA package. The antenna can be fabricated at low cost by a conventional BGA package fabrication process. The BGA package is mounted on a printed circuit board (PCB) that consists of resin substrate, such as FR-4. The broadband impedance characteristic is achieved by adjusting the position of the metal pad for wire bonding. The antenna gain is improved by forming cranked ledges and notches in the metal patterns of the PCB, and the wide-angle radiation characteristic is realized. The sizes of the fabricated antenna and BGA package are approximately 0.6 mm $\,\times \,$ 1.0 mm $\,\times \,$ 0.3 mm and 9.0 mm $\,\times \,$ 9.0 mm $\,\times \,$ 0.9 mm, respectively. Performing measurements, the antenna gain with the PCB is from $-$ 2.4 to 4.9 dBi over the 57- to 65-GHz frequency range and over an angular range of 60 $^\circ$ in the horizontal plane.
Yukako Tsutsumi - One of the best experts on this subject based on the ideXlab platform.
-
bonding wire Loop antenna in standard ball grid array package for 60 ghz short range wireless communication
IEEE Transactions on Antennas and Propagation, 2013Co-Authors: Yukako Tsutsumi, Hiroki Shoki, Takayoshi Ito, Koh Hashimoto, Shuichi Obayashi, Hideo KasamiAbstract:High-speed short-range wireless communication systems are expected to utilize the 60-GHz band. This paper presents a bonding wire Loop antenna in a standard ball grid array (BGA) package for 60-GHz short-range wireless communication. The proposed antenna has a Loop Shape and consists of two bonding wires connecting to a complementary metal–oxide–semiconductor (CMOS) chip and a metal plate on an interposer in a BGA package. The antenna can be fabricated at low cost by a conventional BGA package fabrication process. The BGA package is mounted on a printed circuit board (PCB) that consists of resin substrate, such as FR-4. The broadband impedance characteristic is achieved by adjusting the position of the metal pad for wire bonding. The antenna gain is improved by forming cranked ledges and notches in the metal patterns of the PCB, and the wide-angle radiation characteristic is realized. The sizes of the fabricated antenna and BGA package are approximately 0.6 mm $\,\times \,$ 1.0 mm $\,\times \,$ 0.3 mm and 9.0 mm $\,\times \,$ 9.0 mm $\,\times \,$ 0.9 mm, respectively. Performing measurements, the antenna gain with the PCB is from $-$ 2.4 to 4.9 dBi over the 57- to 65-GHz frequency range and over an angular range of 60 $^\circ$ in the horizontal plane.
-
bonding wire Loop antenna built into standard bga package for 60 ghz short range wireless communication
International Microwave Symposium, 2011Co-Authors: Yukako Tsutsumi, Hiroki Shoki, Shuichi Obayashi, Tasuku MorookaAbstract:The unlicensed 60 GHz frequency band is suitable for high-speed wireless systems with transmission rates of 1 Gbps or more. In this paper, we propose a bonding wire antenna built into a BGA package for 60 GHz short-range wireless communication. This antenna utilizes two bonding wires and a metal plate on an interposer in a BGA package and has a Loop Shape. The proposed antenna is built into a standard BGA package without special modification, so that it can be fabricated at low cost by conventional BGA package fabrication process. The first and unique evaluation of the antenna fully sealed by encapsulation resin was done by measurement. We describe the operation mechanism of the proposed antenna, the design procedure and the measurement results.
Socrates Dokos - One of the best experts on this subject based on the ideXlab platform.
-
a multiphysics biventricular cardiac model simulations with a left ventricular assist device
Frontiers in Physiology, 2018Co-Authors: Azam Ahmad Bakir, Amr Al Abed, Michael C Stevens, Nigel H Lovell, Socrates DokosAbstract:Computational models have become essential in predicting medical device efficacy prior to clinical studies. To investigate the performance of a left-ventricular assist device (LVAD), a fully-coupled cardiac fluid-electromechanics finite element model was developed, incorporating electrical activation, passive and active myocardial mechanics, as well as blood hemodynamics solved simultaneously in an idealized biventricular geometry. Electrical activation was initiated using a simplified Purkinje network with one-way coupling to the surrounding myocardium. Phenomenological action potential and excitation-contraction equations were adapted to trigger myocardial contraction. Action potential propagation was formulated within a material frame to emulate gap junction-controlled propagation, such that the activation sequence was independent of myocardial deformation. Passive cardiac mechanics were governed by a transverse isotropic hyperelastic constitutive formulation. Blood velocity and pressure were determined by the incompressible Navier-Stokes formulations with a closed-Loop Windkessel circuit governing the circulatory load. To investigate heart-LVAD interaction, we reduced the left ventricular (LV) contraction stress to mimic a failing heart, and inserted a LVAD cannula at the LV apex with continuous flow governing the outflow rate. A proportional controller was implemented to determine the pump motor voltage whilst maintaining pump motor speed. Following LVAD insertion, the model revealed a change in the LV pressure-volume Loop Shape from rectangular to triangular. At higher pump speeds, aortic ejection ceased and the LV decompressed to smaller end diastolic volumes. After multiple cycles, the LV cavity gradually collapsed along with a drop in pump motor current. The model was therefore able to predict ventricular collapse, indicating its utility for future development of control algorithms and pre-clinical testing of LVADs to avoid LV collapse in recipients.
-
Data_Sheet_1_A Multiphysics Biventricular Cardiac Model: Simulations With a Left-Ventricular Assist Device.pdf
2018Co-Authors: Azam Ahmad Bakir, Amr Al Abed, Michael C Stevens, Nigel H Lovell, Socrates DokosAbstract:Computational models have become essential in predicting medical device efficacy prior to clinical studies. To investigate the performance of a left-ventricular assist device (LVAD), a fully-coupled cardiac fluid-electromechanics finite element model was developed, incorporating electrical activation, passive and active myocardial mechanics, as well as blood hemodynamics solved simultaneously in an idealized biventricular geometry. Electrical activation was initiated using a simplified Purkinje network with one-way coupling to the surrounding myocardium. Phenomenological action potential and excitation-contraction equations were adapted to trigger myocardial contraction. Action potential propagation was formulated within a material frame to emulate gap junction-controlled propagation, such that the activation sequence was independent of myocardial deformation. Passive cardiac mechanics were governed by a transverse isotropic hyperelastic constitutive formulation. Blood velocity and pressure were determined by the incompressible Navier-Stokes formulations with a closed-Loop Windkessel circuit governing the circulatory load. To investigate heart-LVAD interaction, we reduced the left ventricular (LV) contraction stress to mimic a failing heart, and inserted a LVAD cannula at the LV apex with continuous flow governing the outflow rate. A proportional controller was implemented to determine the pump motor voltage whilst maintaining pump motor speed. Following LVAD insertion, the model revealed a change in the LV pressure-volume Loop Shape from rectangular to triangular. At higher pump speeds, aortic ejection ceased and the LV decompressed to smaller end diastolic volumes. After multiple cycles, the LV cavity gradually collapsed along with a drop in pump motor current. The model was therefore able to predict ventricular collapse, indicating its utility for future development of control algorithms and pre-clinical testing of LVADs to avoid LV collapse in recipients.
-
a multiphysics biventricular cardiac model simulations with a left ventricular assist device
Frontiers in Physiology, 2018Co-Authors: Azam Ahmad Bakir, Amr Al Abed, Michael C Stevens, Nigel H Lovell, Socrates DokosAbstract:Computational models have become essential in predicting medical device efficacy prior to clinical studies. To investigate the performance of a left-ventricular assist device (LVAD), a fully-coupled cardiac fluid-electromechanics finite element model was developed, incorporating electrical activation, passive and active myocardial mechanics, as well as blood hemodynamics solved simultaneously in an idealized biventricular geometry. Electrical activation was initiated using a simplified Purkinje network with one-way coupling to the surrounding myocardium. Phenomenological action potential and excitation-contraction equations were adapted to trigger myocardial contraction. Action potential propagation was formulated within a material frame to emulate gap junction-controlled propagation, such that the activation sequence was independent of myocardial deformation. Passive cardiac mechanics were governed by a transverse isotropic hyperelastic constitutive formulation. Blood velocity and pressure were determined by the incompressible Navier-Stokes formulations with a closed-Loop Windkessel circuit governing the circulatory load. To investigate heart-LVAD interaction, we reduced the left ventricular (LV) contraction stress to mimic a failing heart, and inserted a LVAD cannula at the LV apex with continuous flow governing the outflow rate. A proportional controller was implemented to determine the pump motor voltage whilst maintaining pump motor speed. Following LVAD insertion, the model revealed a change in the LV pressure-volume Loop Shape from rectangular to triangular. At higher pump speeds, aortic ejection ceased and the LV decompressed to smaller end diastolic volumes. After multiple cycles, the LV cavity gradually collapsed along with a drop in pump motor current. The model was therefore able to predict ventricular collapse, indicating its utility for future development of control algorithms and pre-clinical testing of LVADs to avoid LV collapse in recipients.
-
Video_5_A Multiphysics Biventricular Cardiac Model: Simulations With a Left-Ventricular Assist Device.AVI
2018Co-Authors: Azam Ahmad Bakir, Amr Al Abed, Michael C Stevens, Nigel H Lovell, Socrates DokosAbstract:Computational models have become essential in predicting medical device efficacy prior to clinical studies. To investigate the performance of a left-ventricular assist device (LVAD), a fully-coupled cardiac fluid-electromechanics finite element model was developed, incorporating electrical activation, passive and active myocardial mechanics, as well as blood hemodynamics solved simultaneously in an idealized biventricular geometry. Electrical activation was initiated using a simplified Purkinje network with one-way coupling to the surrounding myocardium. Phenomenological action potential and excitation-contraction equations were adapted to trigger myocardial contraction. Action potential propagation was formulated within a material frame to emulate gap junction-controlled propagation, such that the activation sequence was independent of myocardial deformation. Passive cardiac mechanics were governed by a transverse isotropic hyperelastic constitutive formulation. Blood velocity and pressure were determined by the incompressible Navier-Stokes formulations with a closed-Loop Windkessel circuit governing the circulatory load. To investigate heart-LVAD interaction, we reduced the left ventricular (LV) contraction stress to mimic a failing heart, and inserted a LVAD cannula at the LV apex with continuous flow governing the outflow rate. A proportional controller was implemented to determine the pump motor voltage whilst maintaining pump motor speed. Following LVAD insertion, the model revealed a change in the LV pressure-volume Loop Shape from rectangular to triangular. At higher pump speeds, aortic ejection ceased and the LV decompressed to smaller end diastolic volumes. After multiple cycles, the LV cavity gradually collapsed along with a drop in pump motor current. The model was therefore able to predict ventricular collapse, indicating its utility for future development of control algorithms and pre-clinical testing of LVADs to avoid LV collapse in recipients.
Sergei V Kalinin - One of the best experts on this subject based on the ideXlab platform.
-
guided search for desired functional responses via bayesian optimization of generative model hysteresis Loop Shape engineering in ferroelectrics
Journal of Applied Physics, 2020Co-Authors: Sergei V Kalinin, Maxim Ziatdinov, Rama K VasudevanAbstract:Advances in theoretical modeling across multiple disciplines have yielded generative models capable of high veracity in predicting macroscopic functional responses of materials emerging as a result of complex non-local interactions. Correspondingly, of interest is the inverse problem of finding the model parameter that will yield desired macroscopic responses, such as stress–strain curves, ferroelectric hysteresis Loops, etc. Here, we suggest and implement Gaussian process based methods that allow to effectively sample the degenerate parameter space of a complex non-local model to output regions of parameter space which yield desired functionalities. We discuss the specific adaptation of the acquisition function and sampling function to make the process efficient and balance the efficient exploration of parameter space for multiple possible minima and exploitation to densely sample the regions of interest where target behaviors are optimized. This approach is illustrated via the hysteresis Loop engineering in ferroelectric materials but can be adapted to other functionalities and generative models.
-
role of measurement voltage on hysteresis Loop Shape in piezoresponse force microscopy
Applied Physics Letters, 2012Co-Authors: Evgheny Strelcov, Yunseok Kim, Jan Chi Yang, Yinghao Chu, Stephen Jesse, Sergei V KalininAbstract:The dependence of field-on and field-off hysteresis Loop Shape in Piezoresponse Force Microscopy (PFM) on driving voltage, Vac, is explored. A nontrivial dependence of hysteresis Loop parameters on measurement conditions is observed. The strategies to distinguish between paraelectric and ferroelectric states with small coercive bias and separate reversible hysteretic and non-hysteretic behaviors are suggested. Generally, measurement of Loop evolution with Vac is a necessary step to establish the veracity of PFM hysteresis measurements.
-
disorder identification in hysteresis data recognition analysis of the random bond random field ising model
Physical Review Letters, 2009Co-Authors: Oleg S Ovchinnikov, Stephen Jesse, P Bintacchit, Susan Troliermckinstry, Sergei V KalininAbstract:An approach for the direct identification of disorder type and strength in physical systems based on recognition analysis of hysteresis Loop Shape is developed. A large number of theoretical examples uniformly distributed in the parameter space of the system is generated and is decorrelated using principal component analysis (PCA). The PCA components are used to train a feed-forward neural network using the model parameters as targets. The trained network is used to analyze hysteresis Loops for the investigated system. The approach is demonstrated using a 2D random-bond-random-field Ising model, and polarization switching in polycrystalline ferroelectric capacitors.
-
domain nucleation and hysteresis Loop Shape in piezoresponse force spectroscopy
Applied Physics Letters, 2006Co-Authors: Anna N Morozovska, Eugene A Eliseev, Sergei V KalininAbstract:Electromechanical hysteresis Loop measurements in piezoresponse force microscopy (PFM) [piezoresponse force spectroscopy (PFS)] have emerged as a powerful technique for probing ferroelectric switching behavior on the nanoscale. Interpretation of PFS data requires the relationship between the domain parameters and PFM signal to be established. Here, the authors analyze the switching process using modified point charge model. The charge parameters are selected to reproduce tip-induced surface potential and tip radius of curvature. The relationship between geometric parameters of semiellipsoidal domain and PFM signal is derived using linear Green’s function theory. The role of domain nucleation on hysteresis Loop is established.
-
domain nucleation and hysteresis Loop Shape in piezoresponse force spectroscopy
arXiv: Materials Science, 2006Co-Authors: Anna N Morozovska, Eugene A Eliseev, Sergei V KalininAbstract:Electromechanical hysteresis Loop measurements in Piezoresponse Force Microscopy (Piezoresponse Force Spectroscopy) have emerged as a powerful technique for probing ferroelectric switching behavior on the nanoscale. Interpretation of PFS data requires the relationship between the domain parameters and PFM signal to be established. Here, we analyze the switching process using a modified point charge model for the electric field of the tip. The charge value and position are selected so that its electric field isopotential surface reproduces the tip with definite radius of curvature. Using linear theory of elasticity the relationship between the sizes of semiellipsoidal domain and PFM signal has been derived. The role of domain nucleation on piezoresponse hysteresis Loop is established.
Hiroki Shoki - One of the best experts on this subject based on the ideXlab platform.
-
bonding wire Loop antenna in standard ball grid array package for 60 ghz short range wireless communication
IEEE Transactions on Antennas and Propagation, 2013Co-Authors: Yukako Tsutsumi, Hiroki Shoki, Takayoshi Ito, Koh Hashimoto, Shuichi Obayashi, Hideo KasamiAbstract:High-speed short-range wireless communication systems are expected to utilize the 60-GHz band. This paper presents a bonding wire Loop antenna in a standard ball grid array (BGA) package for 60-GHz short-range wireless communication. The proposed antenna has a Loop Shape and consists of two bonding wires connecting to a complementary metal–oxide–semiconductor (CMOS) chip and a metal plate on an interposer in a BGA package. The antenna can be fabricated at low cost by a conventional BGA package fabrication process. The BGA package is mounted on a printed circuit board (PCB) that consists of resin substrate, such as FR-4. The broadband impedance characteristic is achieved by adjusting the position of the metal pad for wire bonding. The antenna gain is improved by forming cranked ledges and notches in the metal patterns of the PCB, and the wide-angle radiation characteristic is realized. The sizes of the fabricated antenna and BGA package are approximately 0.6 mm $\,\times \,$ 1.0 mm $\,\times \,$ 0.3 mm and 9.0 mm $\,\times \,$ 9.0 mm $\,\times \,$ 0.9 mm, respectively. Performing measurements, the antenna gain with the PCB is from $-$ 2.4 to 4.9 dBi over the 57- to 65-GHz frequency range and over an angular range of 60 $^\circ$ in the horizontal plane.
-
bonding wire Loop antenna built into standard bga package for 60 ghz short range wireless communication
International Microwave Symposium, 2011Co-Authors: Yukako Tsutsumi, Hiroki Shoki, Shuichi Obayashi, Tasuku MorookaAbstract:The unlicensed 60 GHz frequency band is suitable for high-speed wireless systems with transmission rates of 1 Gbps or more. In this paper, we propose a bonding wire antenna built into a BGA package for 60 GHz short-range wireless communication. This antenna utilizes two bonding wires and a metal plate on an interposer in a BGA package and has a Loop Shape. The proposed antenna is built into a standard BGA package without special modification, so that it can be fabricated at low cost by conventional BGA package fabrication process. The first and unique evaluation of the antenna fully sealed by encapsulation resin was done by measurement. We describe the operation mechanism of the proposed antenna, the design procedure and the measurement results.
