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Full-Text Articles in Engineering
Inherited Redundancy And Configurability Utilization For Repairing Nanowire Crossbars With Clustered Defects, Yadunandana Yellambalase, Minsu Choi, Yong-Bin Kim
Inherited Redundancy And Configurability Utilization For Repairing Nanowire Crossbars With Clustered Defects, Yadunandana Yellambalase, Minsu Choi, Yong-Bin Kim
Electrical and Computer Engineering Faculty Research & Creative Works
With the recent development of nanoscale materials and assembly techniques, it is envisioned to build high-density reconfigurable systems which have never been achieved by the photolithography. Various reconfigurable architectures have been proposed based on nanowire crossbar structure as the primitive building block. Unfortunately, high-density systems consisting of nanometer-scale elements are likely to have many imperfections and variations; thus, defect-tolerance is considered as one of the most exigent challenges. In this paper, we evaluate three different logic mapping algorithms with defect avoidance to circumvent clustered defective crosspoints in nanowire reconfigurable crossbar architectures. The effectiveness of inherited redundancy and configurability utilization is …
Signal Link-Path Characterization Up To 20 Ghz Based On A Stripline Structure, Jianmin Zhang, James L. Drewniak, David Pommerenke, Richard E. Dubroff, Zhiping Yang, Wheling Cheng, John C. Fisher, Sergio Camerlo
Signal Link-Path Characterization Up To 20 Ghz Based On A Stripline Structure, Jianmin Zhang, James L. Drewniak, David Pommerenke, Richard E. Dubroff, Zhiping Yang, Wheling Cheng, John C. Fisher, Sergio Camerlo
Electrical and Computer Engineering Faculty Research & Creative Works
Dielectric properties and losses are two critical issues in signal link-path characterization. To obtain the substrate dielectric properties for a planar transmission line, an analytical solution is derived and validated based on a stripline structure and measured scattering parameters with TRL de-embedding. The characterized dielectric property is used to evaluate dielectric loss and conductor loss. The total loss is thereby found from their summation. The calculated total loss is compared to the measured total loss, and the conductor loss and dielectric loss are then quantifiable. Since the conventional description using the loss tangent and dielectric constant to represent material properties …
High Resolution Millimeter Wave Detection Of Vertical Cracks In The Space Shuttle External Tank Spray-On-Foam Insulation (Sofi), Sergey Kharkovsky, R. Zoughi, F. L. Hepburn
High Resolution Millimeter Wave Detection Of Vertical Cracks In The Space Shuttle External Tank Spray-On-Foam Insulation (Sofi), Sergey Kharkovsky, R. Zoughi, F. L. Hepburn
Electrical and Computer Engineering Faculty Research & Creative Works
Space Shuttle Columbia's catastrophic failure, the separation of a piece of spray-on-foam insulation (SOFI) from the external tank (ET) in the Space Shuttle Discovery's flight in 2005 and crack detected in its ET foam prior to its successful launch in 2006 emphasize the need for effective nondestructive methods for inspecting the shuttle ET SOFI. Millimeter wave nondestructive testing methods have been considered as potential and effective inspection tools for evaluating the integrity of the SOFI. This paper presents recent results of an investigation for the purpose of detecting vertical cracks in SOFI panels using a focused millimeter wave (150 GHz) …
A Method For Charactering Emi Coupling Paths And Source Properties In Complex Systems, Shishuang Sun, Gang Feng, Chong Ding, David Pommerenke, James L. Drewniak
A Method For Charactering Emi Coupling Paths And Source Properties In Complex Systems, Shishuang Sun, Gang Feng, Chong Ding, David Pommerenke, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
A method for charactering EMI coupling paths in complex systems is presented. While it is relatively easy to determine the EMI antenna structures or the sources of EMI, it is often quite difficult to identify, and even more difficult to quantify coupling paths. This paper introduces a measurement-based method to quantify EMI coupling paths, and the source strengths can be indirectly determined by applying linear system theory. Circuit design guidelines, e.g., the permissible even-mode current in a differential signal, can be derived with the knowledge of the coupling path and EMI limits. Moreover, the EMI can be better predicted with …
Hysteresis And Delta Modulation Control Of Converters Using Sensorless Current Mode, Jonathan W. Kimball, Philip T. Krein, Yongxiang Chen
Hysteresis And Delta Modulation Control Of Converters Using Sensorless Current Mode, Jonathan W. Kimball, Philip T. Krein, Yongxiang Chen
Electrical and Computer Engineering Faculty Research & Creative Works
Sensorless current mode (SCM) is a control formulation for dc-dc converters that results in voltage-source characteristics, excellent open-loop tracking, and near-ideal source rejection. Hysteresis and delta modulation are well-known, easy-to-construct large-signal methods for switched systems. Combining either large-signal method with SCM creates a controller that is simpler and more robust than a pulse-width modulation (PWM) based controller. The small-signal advantages of PWM-based SCM are retained and expanded to include converter response to large-signal disturbances. These approaches can be used with any converter topology over a broad range of operating conditions. In the present work, hysteresis and delta modulation SCM controllers …
High Accuracy Disbond Thickness Estimation Scheme Employing Multiple-Frequency Near-Field Microwave Measurements, Mohamed A. Abou-Khousa, R. Zoughi
High Accuracy Disbond Thickness Estimation Scheme Employing Multiple-Frequency Near-Field Microwave Measurements, Mohamed A. Abou-Khousa, R. Zoughi
Electrical and Computer Engineering Faculty Research & Creative Works
Microwave nondestructive evaluation (NDE) techniques have shown great potential for disbond detection in multi-layer dielectric structures. However, a quantitative disbond thickness estimation scheme has not been introduced yet. In this paper, we propose a maximum-likelihood (ML) disbond thickness estimation scheme utilizing multiple independent measurements obtained at different frequencies. By simulations and experiments, we show that the proposed scheme produces highly accurate disbond thickness estimates.