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Full-Text Articles in Engineering

Risk-Based Critical Infrastructure Priorities For Emp And Solar Storms, George H. Baker Iii Oct 2011

Risk-Based Critical Infrastructure Priorities For Emp And Solar Storms, George H. Baker Iii

George H Baker

Two electromagnetic phenomena have the potential to create continental-scale disasters. The first, nuclear electromagnetic pulse (EMP), results from a nuclear detonation high above the tropopause. The second, a major solar storm, or "solar tsunami" occurs naturally when an intense wave of charged particles from the sun perturbs the earth's magnetic field. Both phenomena can debilitate electrical and electronic systems necessary for the operation of infrastructure systems and services. One reason why a U.S. protection program has yet to be initiated is that policy makers continue to wrestle with the question of where to begin, given the Department of Homeland Security’s …


Risk-Based Critical Infrastructure Protection Priorities For Emp And Solar Storms, George H. Baker Iii Sep 2011

Risk-Based Critical Infrastructure Protection Priorities For Emp And Solar Storms, George H. Baker Iii

George H Baker

The Commission to Assess the Threat to the United States from Electromagnetic Pulse Attack has provided a compelling case for protecting civilian infrastructure against the effects of EMP. As with protecting infrastructure against any hazard, it will be important to take a risk-based priority approach for EMP, recognizing that it is fiscally impracticable to protect everything. In this regard, EMP is particularly challenging in that it interferes with electrical and electronic data, control, transmission, and communication systems organic to nearly all infrastructures in a simultaneous and wide-scale manner. And, for nuclear burst altitudes of 100s of kilometers, the exposed geography …


Aluminum Nitride Reconfigurable Rf-Mems Front-Ends, Augusto Tazzoli, Matteo Rinaldi, Chengjie Zuo, Nipun Sinha, Jan Van Der Spiegel, Gianluca Piazza Sep 2011

Aluminum Nitride Reconfigurable Rf-Mems Front-Ends, Augusto Tazzoli, Matteo Rinaldi, Chengjie Zuo, Nipun Sinha, Jan Van Der Spiegel, Gianluca Piazza

Matteo Rinaldi

Aluminum Nitride based piezoelectric microelectromechanical systems (MEMS) technology has the potential to develop a fully integrated radio frequency (RF) platform that satisfies the requirements of next-generation communication standards: reconfigurability, miniaturization, and low power consumption. Here we report on the recent developments of this AlN thin-film based technology, namely resonators, filters, oscillators and switches. These examples highlight how MEMS will enable the mass manufacturing of reconfigurable RF front-ends.


Emp: A Brief Tutorial, George H. Baker Iii Jul 2011

Emp: A Brief Tutorial, George H. Baker Iii

George H Baker

A nuclear detonation at altitudes from about 30 to 500 kilometers generates a strong electromagnetic pulse (EMP) that propagates to points on the ground within the line-of-sight of the burst. For bursts above 100 kilometers, electronics can be affected over continental scale areas. The EMP induces large voltages and currents in antennas and cables of electronic systems that will upset operation or damage circuit components if protection measures are not present. The article provides a brief tutorial on EMP environments, effects and protection.


High Power Electromagnetic Weapons: A Brief Tutorial, George H. Baker Iii Jul 2011

High Power Electromagnetic Weapons: A Brief Tutorial, George H. Baker Iii

George H Baker

High power electromagnetic weapons, also referred to as high power radiofrequency (HPRF) weapons, are a type of directed energy weapons. The system effects of high power electromagnetic environments are well recognized by world scientific and military communities. Former CIA Director John Deutch has said that, "the electron is the ultimate precision-guided weapon." In the course of the investigation ofnuclear EMP effects on electronics during the Cold War period, it became evident that garden variety, unprotected electronics would malfunction, in some cases burn out, in the presence of electromagnetic fields in the hundreds to thousands of volts per meter. The EMP …


Design, Modeling And Control Strategy Of Pv/Fc Hybrid Power System, Dr. Adel A. Elbaset Jul 2011

Design, Modeling And Control Strategy Of Pv/Fc Hybrid Power System, Dr. Adel A. Elbaset

Dr. Adel A. Elbaset

This paper describes development of a general methodology of an autonomous PV/FC system composed of photovoltaic (PV), electrolyzer, hydrogen storage tank and fuel cell (FC). The aim of this paper is to determine optimum design, control strategy, economic and performance of a PV/FC hybrid power generation system without battery storage taking into account all losses in the system. The paper also presents a computer program based on Matlab software to determine optimum design, control strategy, economic and performance of an autonomous PV/FC hybrid power generation system. The computer program develops to size system components in order to match the load …


Purely Electronic Switching With High Uniformity, Resistance Tunability, And Good Retention In Pt-Dispersed Sio2 Thin Films For Reram, Albert Chen Jun 2011

Purely Electronic Switching With High Uniformity, Resistance Tunability, And Good Retention In Pt-Dispersed Sio2 Thin Films For Reram, Albert Chen

Albert B Chen

Resistance switching memory operating by a purely electronic switching mechanism, which was first realized in Pt-dispersed SiO2 thin films, satisfies criteria including high uniformity, fast switching speed, and long retention for non-volatile memory application. This resistive element obeys Ohm's law for the area dependence, but its resistance exponentially increases with the film thickness, which provides new freedom to tailor the device characteristics.


High-Throughput Assembly Of Nanoelements In Nanoporous Alumina Templates, Evin Gultepe, Dattatri K. Nagesha, Latika Menon, Ahmed A. Busnaina, Srinivas Sridhar Jun 2011

High-Throughput Assembly Of Nanoelements In Nanoporous Alumina Templates, Evin Gultepe, Dattatri K. Nagesha, Latika Menon, Ahmed A. Busnaina, Srinivas Sridhar

Dattatri K. Nagesha

The authors demonstrate a nanofabrication method utilizing nanoporous alumina templates which involves directed three dimensional assembly of nanoparticles inside the pores by means of an electrophoretic technique. In their demonstration, they have assembled polystyrene nanobeads with diameter of 50 nm inside nanopore arrays of height of 250 nm and diameter of 80 nm. Such a technique is particularly useful for large-scale, rapid assembly of nanoelements for potential device applications.


High-Throughput Assembly Of Nanoelements In Nanoporous Alumina Templates, Evin Gultepe, Dattatri K. Nagesha, Latika Menon, Ahmed A. Busnaina, Srinivas Sridhar Jun 2011

High-Throughput Assembly Of Nanoelements In Nanoporous Alumina Templates, Evin Gultepe, Dattatri K. Nagesha, Latika Menon, Ahmed A. Busnaina, Srinivas Sridhar

Latika Menon

The authors demonstrate a nanofabrication method utilizing nanoporous alumina templates which involves directed three dimensional assembly of nanoparticles inside the pores by means of an electrophoretic technique. In their demonstration, they have assembled polystyrene nanobeads with diameter of 50 nm inside nanopore arrays of height of 250 nm and diameter of 80 nm. Such a technique is particularly useful for large-scale, rapid assembly of nanoelements for potential device applications.


Three Dimensional Controlled Assembly Of Gold Nanoparticles Using A Micromachined Platform, Nishant Khanduja, Selvapraba Selvarasah, Chia-Ling Chen, Mehmet R. Dokmeci, Xugang Xiong, Prashanth Makaram, Ahmed A. Busnaina Jun 2011

Three Dimensional Controlled Assembly Of Gold Nanoparticles Using A Micromachined Platform, Nishant Khanduja, Selvapraba Selvarasah, Chia-Ling Chen, Mehmet R. Dokmeci, Xugang Xiong, Prashanth Makaram, Ahmed A. Busnaina

Ahmed A. Busnaina

By using optical lithographic procedures, the authors present a micromachined platform for large scale three dimensional (3D) assembly of gold nanoparticles with diameters of ∼ 50 nm. The gold nanoparticles are formed into 3D low resistance bridges (two terminal resistance of ∼ 40 Ω) interconnecting the two microelectrodes using ac dielectrophoresis. The thickness of the parylene interlevel dielectric can be adjusted to vary the height of the 3D platform for meeting different application requirements. This research represents a step towards realizing high density, three dimensional structures and devices for applications such as nanosensors, vertical integration of nanosystems, and characterization of …


Scalable Nanotemplate Assisted Directed Assembly Of Single Walled Carbon Nanotubes For Nanoscale Devices, Prashanth Makaram, Sivasubramanian Somu, Xugang Xiong, Ahmed A. Busnaina, Yung-Joon Jung, Nicol E. Mcgruer Jun 2011

Scalable Nanotemplate Assisted Directed Assembly Of Single Walled Carbon Nanotubes For Nanoscale Devices, Prashanth Makaram, Sivasubramanian Somu, Xugang Xiong, Ahmed A. Busnaina, Yung-Joon Jung, Nicol E. Mcgruer

Ahmed A. Busnaina

The authors demonstrate precise alignment and controlled assembly of single wall nanotube (SWNT) bundles at a fast rate over large areas by combining electrophoresis and dip coating processes. SWNTs in solution are assembled on prepatterned features that are 80 nm wide and separated by 200 nm. The results show that the direction of substrate withdrawal significantly affects the orientation and alignment of the assembled SWNT bundles. I-V characterization is carried out to demonstrate electrical continuity of these assembled SWNT bundles.


Directed Assembly Of Gold Nanoparticle Nanowires And Networks For Nanodevices, Xugang Xiong, Ahmed A. Busnaina, Selvapraba Selvarasah, Sivasubramanian Somu, Ming Wei, Joey Mead, Chia-Ling Chen, Juan Aceros, Prashanth Makaram, Mehmet R. Dokmeci Jun 2011

Directed Assembly Of Gold Nanoparticle Nanowires And Networks For Nanodevices, Xugang Xiong, Ahmed A. Busnaina, Selvapraba Selvarasah, Sivasubramanian Somu, Ming Wei, Joey Mead, Chia-Ling Chen, Juan Aceros, Prashanth Makaram, Mehmet R. Dokmeci

Ahmed A. Busnaina

Alternating electric field is used to assemble gold nanoparticle nanowires from liquid suspensions. The effects of electrode geometry and the dielectrophoresis force on the chaining and branching of nanowire formation are investigated. The nanowire assembly processes are modeled using finite element calculations, and the particle trajectories under the combined influence of dielectrophoresis force and viscous drag are simulated. Nanoparticle nanowires with 10 nm resolution are fabricated. The wires can be further oriented along an externally introduced flow. This work provides an approach towards rapid assembly and organization of ultrasmall nanoparticle networks.


High-Throughput Assembly Of Nanoelements In Nanoporous Alumina Templates, Evin Gultepe, Dattatri K. Nagesha, Latika Menon, Ahmed A. Busnaina, Srinivas Sridhar Jun 2011

High-Throughput Assembly Of Nanoelements In Nanoporous Alumina Templates, Evin Gultepe, Dattatri K. Nagesha, Latika Menon, Ahmed A. Busnaina, Srinivas Sridhar

Ahmed A. Busnaina

The authors demonstrate a nanofabrication method utilizing nanoporous alumina templates which involves directed three dimensional assembly of nanoparticles inside the pores by means of an electrophoretic technique. In their demonstration, they have assembled polystyrene nanobeads with diameter of 50 nm inside nanopore arrays of height of 250 nm and diameter of 80 nm. Such a technique is particularly useful for large-scale, rapid assembly of nanoelements for potential device applications.


Experimental Study Of Shoot-Through Control Methods For Z-Source Inverter, Omar Ellabban, Joeri Van Mierlo, Philippe Lataire May 2011

Experimental Study Of Shoot-Through Control Methods For Z-Source Inverter, Omar Ellabban, Joeri Van Mierlo, Philippe Lataire

Omar Ellabban

This paper presents a simulation and experimental comparative analysis of the Z-source inverter (ZSI) with four different shoot-through (ST) control methods, namely: the simple boost control, the maximum boost control, the maximum constant boost control and the modified space vector modulation boost control methods. A review of these methods is presented with a summary of all expressions. A prototype of a 30 kW ZSI is designed and implemented. The eZdsp™ F2808 evaluation board is used for the realization of the shoot-through control methods and the real time workshop (RTW) is used for automatic code generation. The paper compares between the …


Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol E. Mcgruer, George G. Adams, Yan Du May 2011

Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol E. Mcgruer, George G. Adams, Yan Du

George G. Adams

We report the observation of two distinct modes of rate-dependent behavior during contact cycling tests. One is a higher pull-off force at low cycling rates and the other is a higher pull-off force at high cycling rates. Subsequent investigation of these contacts using scanning electron microscopy (SEM) demonstrates that these two rate-dependent modes can be related to brittle and ductile separation modes. The former behavior is indicative of brittle separation, whereas the latter accompanies ductile separation. Thus by monitoring the rate dependence of the pull-off force, the type of separation mode can be identified during cycling without interrupting the test …


Contact Resistance Study Of Noble Metals And Alloy Films Using A Scanning Probe Microscope Test Station, Lei Chen, H. Lee, Z. J. Guo, Nicol E. Mcgruer, K. W. Gilbert, S. Mall, Kevin D. Leedy, George G. Adams May 2011

Contact Resistance Study Of Noble Metals And Alloy Films Using A Scanning Probe Microscope Test Station, Lei Chen, H. Lee, Z. J. Guo, Nicol E. Mcgruer, K. W. Gilbert, S. Mall, Kevin D. Leedy, George G. Adams

George G. Adams

The proper selection of electrical contact materials is one of the critical steps in designing a metal contact microelectromechanical system (MEMS) switch. Ideally, the contact should have both very low contact resistance and high wear resistance. Unfortunately this combination cannot be easily achieved with the contact materials currently used in macroswitches because the available contact force in microswitches is generally insufficient (less than 1 mN) to break through nonconductive surface layers. As a step in the materials selection process, three noble metals, platinum (Pt), rhodium (Rh), ruthenium (Ru), and their alloys with gold (Au) were deposited as thin films on …


A Parameter Study Of Separation Modes Of Adhering Microcontacts, Yan Du, George G. Adams, Nicol E. Mcgruer, Izhak Etsion May 2011

A Parameter Study Of Separation Modes Of Adhering Microcontacts, Yan Du, George G. Adams, Nicol E. Mcgruer, Izhak Etsion

George G. Adams

A finite element model was developed to study adhesion of elastic-plastic microcontacts in a previous investigation. An interesting result was the identification of two distinct separation modes, i.e. brittle and ductile separation. In the current study, that model is used to conduct a series of simulations to determine the influence of four nondimensional parameters (including the maximum load parameter) on the contact and on the separation modes. The results show that the parameter S (the ratio of the theoretical stress to the hardness) and δƒ/δc (representing the loading level) are the most important. Smaller S can only lead to brittle …


Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol Mcgruer, George Adams, Yan Du May 2011

Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol Mcgruer, George Adams, Yan Du

Nicol E. McGruer

We report the observation of two distinct modes of rate-dependent behavior during contact cycling tests. One is a higher pull-off force at low cycling rates and the other is a higher pull-off force at high cycling rates. Subsequent investigation of these contacts using scanning electron microscopy (SEM) demonstrates that these two rate-dependent modes can be related to brittle and ductile separation modes. The former behavior is indicative of brittle separation, whereas the latter accompanies ductile separation. Thus by monitoring the rate dependence of the pull-off force, the type of separation mode can be identified during cycling without interrupting the test …


Contact Resistance Study Of Noble Metals And Alloy Films Using A Scanning Probe Microscope Test Station, Lei Chen, H. Lee, Z. J. Guo, Nicol E. Mcgruer, K. W. Gilbert, S. Mall, Kevin D. Leedy, George G. Adams May 2011

Contact Resistance Study Of Noble Metals And Alloy Films Using A Scanning Probe Microscope Test Station, Lei Chen, H. Lee, Z. J. Guo, Nicol E. Mcgruer, K. W. Gilbert, S. Mall, Kevin D. Leedy, George G. Adams

Nicol E. McGruer

The proper selection of electrical contact materials is one of the critical steps in designing a metal contact microelectromechanical system (MEMS) switch. Ideally, the contact should have both very low contact resistance and high wear resistance. Unfortunately this combination cannot be easily achieved with the contact materials currently used in macroswitches because the available contact force in microswitches is generally insufficient (less than 1 mN) to break through nonconductive surface layers. As a step in the materials selection process, three noble metals, platinum (Pt), rhodium (Rh), ruthenium (Ru), and their alloys with gold (Au) were deposited as thin films on …


A Parameter Study Of Separation Modes Of Adhering Microcontacts, Yan Du, George G. Adams, Nicol E. Mcgruer, Izhak Etsion May 2011

A Parameter Study Of Separation Modes Of Adhering Microcontacts, Yan Du, George G. Adams, Nicol E. Mcgruer, Izhak Etsion

Nicol E. McGruer

A finite element model was developed to study adhesion of elastic-plastic microcontacts in a previous investigation. An interesting result was the identification of two distinct separation modes, i.e. brittle and ductile separation. In the current study, that model is used to conduct a series of simulations to determine the influence of four nondimensional parameters (including the maximum load parameter) on the contact and on the separation modes. The results show that the parameter S (the ratio of the theoretical stress to the hardness) and δƒ/δc (representing the loading level) are the most important. Smaller S can only lead to brittle …


Scalable Nanotemplate Assisted Directed Assembly Of Single Walled Carbon Nanotubes For Nanoscale Devices, Prashanth Makaram, Sivasubramanian Somu, Xugang Xiong, Ahmed A. Busnaina, Yung-Joon Jung, Nicol E. Mcgruer May 2011

Scalable Nanotemplate Assisted Directed Assembly Of Single Walled Carbon Nanotubes For Nanoscale Devices, Prashanth Makaram, Sivasubramanian Somu, Xugang Xiong, Ahmed A. Busnaina, Yung-Joon Jung, Nicol E. Mcgruer

Nicol E. McGruer

The authors demonstrate precise alignment and controlled assembly of single wall nanotube (SWNT) bundles at a fast rate over large areas by combining electrophoresis and dip coating processes. SWNTs in solution are assembled on prepatterned features that are 80 nm wide and separated by 200 nm. The results show that the direction of substrate withdrawal significantly affects the orientation and alignment of the assembled SWNT bundles. I-V characterization is carried out to demonstrate electrical continuity of these assembled SWNT bundles.


Parallel Arrays Of Individually Addressable Single-Walled Carbon Nanotube Field-Effect Transistors, Sarah Lastella, Govind Mallick, Raymond Woo, Shashi Karna, David Rider, Ian Manners, Yung-Joon Jung, Chang Ryu, Pulickel Ajayan May 2011

Parallel Arrays Of Individually Addressable Single-Walled Carbon Nanotube Field-Effect Transistors, Sarah Lastella, Govind Mallick, Raymond Woo, Shashi Karna, David Rider, Ian Manners, Yung-Joon Jung, Chang Ryu, Pulickel Ajayan

Yung Joon Jung

High-throughput field-effect transistors (FETs) containing over 300 disentangled, high-purity chemical-vapor-deposition-grown single-walled carbon nanotube (SWNT) channels have been fabricated in a three-step process that creates more than 160 individually addressable devices on a single silicon chip. This scheme gives a 96% device yield with output currents averaging 5.4 mA and reaching up to 17 mA at a 300 mV bias. Entirely semiconducting FETs are easily realized by a high current selective destruction of metallic tubes. The excellent dispersity and nearly-defect-free quality of the SWNT channels make these devices also useful for nanoscale chemical and biological sensor applications.


Scalable Nanotemplate Assisted Directed Assembly Of Single Walled Carbon Nanotubes For Nanoscale Devices, Prashanth Makaram, Sivasubramanian Somu, Xugang Xiong, Ahmed A. Busnaina, Yung-Joon Jung, Nicol E. Mcgruer May 2011

Scalable Nanotemplate Assisted Directed Assembly Of Single Walled Carbon Nanotubes For Nanoscale Devices, Prashanth Makaram, Sivasubramanian Somu, Xugang Xiong, Ahmed A. Busnaina, Yung-Joon Jung, Nicol E. Mcgruer

Yung Joon Jung

The authors demonstrate precise alignment and controlled assembly of single wall nanotube (SWNT) bundles at a fast rate over large areas by combining electrophoresis and dip coating processes. SWNTs in solution are assembled on prepatterned features that are 80 nm wide and separated by 200 nm. The results show that the direction of substrate withdrawal significantly affects the orientation and alignment of the assembled SWNT bundles. I-V characterization is carried out to demonstrate electrical continuity of these assembled SWNT bundles.


Directed Assembly Of Gold Nanoparticle Nanowires And Networks For Nanodevices, Xugang Xiong, Ahmed A. Busnaina, Selvapraba Selvarasah, Sivasubramanian Somu, Ming Wei, Joey Mead, Chia-Ling Chen, Juan Aceros, Prashanth Makaram, Mehmet R. Dokmeci May 2011

Directed Assembly Of Gold Nanoparticle Nanowires And Networks For Nanodevices, Xugang Xiong, Ahmed A. Busnaina, Selvapraba Selvarasah, Sivasubramanian Somu, Ming Wei, Joey Mead, Chia-Ling Chen, Juan Aceros, Prashanth Makaram, Mehmet R. Dokmeci

Mehmet R. Dokmeci

Alternating electric field is used to assemble gold nanoparticle nanowires from liquid suspensions. The effects of electrode geometry and the dielectrophoresis force on the chaining and branching of nanowire formation are investigated. The nanowire assembly processes are modeled using finite element calculations, and the particle trajectories under the combined influence of dielectrophoresis force and viscous drag are simulated. Nanoparticle nanowires with 10 nm resolution are fabricated. The wires can be further oriented along an externally introduced flow. This work provides an approach towards rapid assembly and organization of ultrasmall nanoparticle networks.


Three Dimensional Controlled Assembly Of Gold Nanoparticles Using A Micromachined Platform, Nishant Khanduja, Selvapraba Selvarasah, Chia-Ling Chen, Mehmet R. Dokmeci, Xugang Xiong, Prashanth Makaram, Ahmed A. Busnaina May 2011

Three Dimensional Controlled Assembly Of Gold Nanoparticles Using A Micromachined Platform, Nishant Khanduja, Selvapraba Selvarasah, Chia-Ling Chen, Mehmet R. Dokmeci, Xugang Xiong, Prashanth Makaram, Ahmed A. Busnaina

Mehmet R. Dokmeci

By using optical lithographic procedures, the authors present a micromachined platform for large scale three dimensional (3D) assembly of gold nanoparticles with diameters of ∼ 50 nm. The gold nanoparticles are formed into 3D low resistance bridges (two terminal resistance of ∼ 40 Ω) interconnecting the two microelectrodes using ac dielectrophoresis. The thickness of the parylene interlevel dielectric can be adjusted to vary the height of the 3D platform for meeting different application requirements. This research represents a step towards realizing high density, three dimensional structures and devices for applications such as nanosensors, vertical integration of nanosystems, and characterization of …


Reconfigurable Cmos Oscillator Based On Multifrequency Aln Contour-Mode Mems Resonators, Matteo Rinaldi, Chengjie Zuo, Jan Van Der Spiegel, Gianluca Piazza Apr 2011

Reconfigurable Cmos Oscillator Based On Multifrequency Aln Contour-Mode Mems Resonators, Matteo Rinaldi, Chengjie Zuo, Jan Van Der Spiegel, Gianluca Piazza

Matteo Rinaldi

This paper reports on the first demonstration of a reconfigurable complementary-metal-oxide-semiconductor (CMOS) oscillator based on microelectromechanical system (MEMS) resonators operating at four different frequencies (268, 483, 690, and 785 MHz). A bank of multifrequency switchable AlN contour-mode MEMS resonators was connected to a single CMOS oscillator circuit that can be configured to selectively operate in four different states with distinct oscillation frequencies. The phase noise (PN) of the reconfigurable oscillator was measured for each of the four different frequencies of operation, showing values between −94 and −70 dBc/Hz at a 1-kHz offset and PN floor values as low as −165 …


Multifrequency Wilkinson Power Divider Using Microstrip Nonuniform Transmission Lines, M. Khalaj-Amirhossein, M. Moghavvemi, Hossein Ameri Mahabadi Apr 2011

Multifrequency Wilkinson Power Divider Using Microstrip Nonuniform Transmission Lines, M. Khalaj-Amirhossein, M. Moghavvemi, Hossein Ameri Mahabadi

Hossein Ameri Mahabadi

A new idea is proposed to modify the conventional Wilkinson power dividers to operate at two or several desired frequencies. The proposed structure contains two Microstrip Nonuniform Transmission Lines (MNTLs) instead of two uniform ones with nearly the same length at the minimum frequency. The strip width of MNTLs is considered variable and is written as a truncated Fourier series. Three nonuniform power dividers are designed and one of them operating at frequencies 1.0, 2.8, and 4.5 GHz is fabricated and measured. The measured results of the fabricated diplexer have a good agreement with the theoretical results.


Automating The Screening Of Microphonic Defects In Automotive Radio Receivers, Chin-Leong Lim Feb 2011

Automating The Screening Of Microphonic Defects In Automotive Radio Receivers, Chin-Leong Lim

Chin-Leong Lim

Microphonics are unwanted electro-acoustic effects in electronic equipment caused by mechanical vibration. Vehicular radio receivers are particularly susceptible due to their traveling over uneven roads, e.g. potholes and bumps. As microphonics influence customers’ perception of product quality, manufacturers actively seek to sieve out receivers exhibiting the worst manifestation of this defect. The IEC 315-4 standard for FM broadcast receivers mandates screening for "unwanted acoustic feedback" by tapping on the receiver housing and then listening for the tell-tale ringing noises at the audio output, i.e. speakers or headphone. However, this subjective method requires trained workers and even then, the repeatability can …


A Dsp Based Dual Loop Digital Controller Design And Implementation Of A High Power Boost Converter For Hybrid Electric Vehicles Applications, Omar Ellabban, Joeri Van Mierlo, Philippe Lataire Feb 2011

A Dsp Based Dual Loop Digital Controller Design And Implementation Of A High Power Boost Converter For Hybrid Electric Vehicles Applications, Omar Ellabban, Joeri Van Mierlo, Philippe Lataire

Omar Ellabban

This paper presents a DSP based direct digital control design and implementation for a high power boost converter. A single loop and dual loop voltage control are digitally implemented and compared. The real time workshop (RTW) is used for automatic real-time code generation. Experimental results of a 20 kW boost converter based on the TMS320F2808 DSP during reference voltage changes, input voltage changes, and load disturbances are presented. The results show that the dual loop control achieves better steady state and transient performance than the single loop control. In addition, the experimental results validate the effectiveness of using the RTW …


Simulation Studies On Ecs Application In A Clean Power Distribution System, Dr. Adel A. Elbaset Jan 2011

Simulation Studies On Ecs Application In A Clean Power Distribution System, Dr. Adel A. Elbaset

Dr. Adel A. Elbaset

Dealing with power distribution system became one of the most important arts in the field of power system, especially in the rapid increase of the distributed generation (DG) penetration to the distribution level which is a vital and important part of the entire power system. In this paper, a very special power distribution system with a unique deployment of distributed generation, such as, photovoltaic and wind generation has been studied. Energy storage system is utilized to play the main role to control the system’s power quality and the system frequency, as load following operation (LFO) and automatic generation control (AGC), …