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Electrical and Electronics Engineering publications abstract of: 06-2010 sorted by title, page: 0
» α-stable interference modeling and cauchy receiver for an IR-UWB Ad Hoc network
Abstract:
In this paper we investigate ad hoc networks based on impulse radio ultra wideband. Due to multiple access, the interference distribution is not Gaussian. One important reason for errors is the presence of close interferers generating pulse collision. However such events are rare and we propose an α-stable model compatible with this fact due to its heavy tailed distribution. We derive the analytical expression of the two significant parameters. They depend on the attenuation coefficient, the users¿ density, the pulse collision probability and the pulse shape. We finally propose receiver strategies (Cauchy receiver and ρ-norm) that outperforms the classical Gaussian receiver.
Autors: El Ghannudi, H.;Clavier, L.;Azzaoui, N.;Septier, F.;Rolland, R.-A.;
Appeared in: IEEE Transactions on Communications
Publication date: Jun 2010, volume: 58, issue:6, pages: 1748 - 1757
Publisher: IEEE
 
» 10-Gb/s Wavelength and Pulse Format Conversion Using Four-Wave Mixing in a GaAs Waveguide
Abstract:
We demonstrate the simultaneous conversion of wavelength and nonreturn-to-zero to return-to-zero (RZ) format at 10 Gb/s, using four-wave mixing in a passive GaAs bulk-waveguide. A conversion efficiency of 28 dB (idler output relative to signal output) and a conversion bandwidth of 48 nm could be achieved in this waveguide, which was fabricated in a single photolithographic step. The conversion efficiency is also characterized and compared with simulated results. The converted RZ on–off keying (RZ-OOK) signal demonstrated a bit-error-rate receiver sensitivity penalty of 1 dB relative to baseline RZ-OOK.
Autors: Apiratikul, P.;Astar, W.;Carter, G. M.;Murphy, T. E.;
Appeared in: IEEE Photonics Technology Letters
Publication date: Jun 2010, volume: 22, issue:12, pages: 872 - 874
Publisher: IEEE
 
» 1901 Transmission Line the great Carquinez Straits crossing [History]
Abstract:
For 96 years, the Carquinez Straits crossing supplied power to the San Francisco Bay Area under severe environmental conditions. It was an extremely reliable crossing and stands as a tribute to the engineers and the construction and maintenance workers who designed, installed, and maintained it over the years. PG&E saved and donated a set of the 1914 pyramid-style insulators to the Northwest Lineman College, and they are now on display at the Oroville, California, campus (see Figure 17). Students and visitors to the college are able to view the last tangible reminder of one of the most significant engineering and construction accomplishments in the history of electric power transmission.
Autors: Drew, A.;
Appeared in: IEEE Power and Energy Magazine
Publication date: Jun 2010, volume: 8, issue:3, pages: 80 - 88
Publisher: IEEE
 
» 1T2R Parallel Mechanisms Without Parasitic Motion
Abstract:
Parasitic motion is a major drawback of the general 1T2R parallel mechanism (PM), where T denotes a translation degree of freedom (DOF) and R a rotational DOF. This paper investigates the type synthesis of the 1T2R PM without parasitic motion. First, a brief review on the planar–spherical bond and its mechanical generators is presented. Then, the difference between the general and special T R motion is discussed. Relations between the parasitic motion and the general and special T R motion are revealed. An infinitesimal 1T2R PM with rotation bifurcation is presented as a special case. Further, the definition of the 1T2R PM without parasitic motion is presented, and the limb bond { ( )}{ ( )} is identified. Geometrical conditions to construct an 1T2R PM without parasitic motion are presented, and nonoverconstrained 1T2R PMs without parasitic motion are synthesized. Idle pairs in the nonoverconstrained 1T2R PMs without parasitic motion are detected. Finally, overconstrained 1T2R PMs without parasitic motion are obtained by removing the idle pairs in the nonoverconstrained 1T2R PMs.
Autors: Li, Q.;Hervé, J.;
Appeared in: IEEE Transactions on Robotics
Publication date: Jun 2010, volume: 26, issue:3, pages: 401 - 410
Publisher: IEEE
 
» 2.2-MW Record Power of the 170-GHz European Preprototype Coaxial-Cavity Gyrotron for ITER
Abstract:
A 2-MW continuous-wave (CW) 170-GHz coaxial-cavity gyrotron for electron cyclotron heating and current drive in the International Thermonuclear Experimental Reactor (ITER) is under development within the European Gyrotron Consortium (EGYCEuropean GYrotron Consortium: CRPP, Switzerland; KIT/FZK, Germany; HELLAS, Greece; CNR, Italy; ENEA, Italy.), a cooperation between European research institutions. To support the development of the industrial prototype of a CW gyrotron, a short-pulse tube (preprototype) is used at KIT Karlsruhe (former FZK) for experimental verification of the design of critical components, like the electron gun, beam tunnel, cavity, and quasi-optical RF output coupler. Significant progress has been achieved recently. In particular, RF output power of up to 2.2 MW with 30% output efficiency has been obtained in single-mode operation at 170 GHz. Furthermore, a new RF output system has been designed, with an efficient conversion of the generated RF power into a Gaussian RF output beam. The results have been successful, yielding a Gaussian mode content 96%.
Autors: Rzesnicki, T.;Piosczyk, B.;Kern, S.;Illy, S.;Jin, J.;Samartsev, A.;Schlaich, A.;Thumm, M.;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Jun 2010, volume: 38, issue:6, pages: 1141 - 1149
Publisher: IEEE
 
» 25 kV/40 kA Protection Inductor for Capacitor Bank of the Wuhan Pulsed High Magnetic Field Facility
Abstract:
A 25 kV/40 kA protection inductor with low stray field was designed and the first prototype was fabricated. The protection inductor protected the thyristor switch in the capacitor bank, limit the current at 40 kA in case of a short circuit. It was designed as a toroidal system consisting of 12 coils evenly distributed in the perimeter of a circle. The inductance could be changed easily by adjusting the number of coils. The structure of coils was optimized to withstand the great electromagnetic force produced by the 40 kA current. The coils were wound by a 4 45 mm copper strip standing on edge. Each coil was externally reinforced by a stainless steel ring tightly enclosing the coil. The first prototype was fabricated. Its inductance and magnetic field were tested. The prototype has been mounted in the 1 MJ module and is now in operation. In this paper, the structure design, fabrication and testing of a new protection inductor are presented. The testing results are discussed. Tested inductance was 1.05 mH and direct resistance was 16 . The first prototype was proved to be successful and 13 more protection inductors will be made after some improvements.
Autors: Lv, Y.;Qiu, L.;Zhang, S.;Tang, Y.;Li, L.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 1211 - 1214
Publisher: IEEE
 
» 2D analytical calculation of the electrostatic potential in lightly doped Schottky barrier Double-Gate MOSFET
Abstract:
In this paper we present a new way to calculate the electrostatic potential of Schottky barrier Double-Gate MOSFETs (SB-DG-MOSFET) in subthreshold region. Compared to the most existing models, our model does not introduce any kind of fitting parameters, all parameters depend on geometry and boundary conditions. This is beneficial for its advantage application in circuit simulations. We solve 2D Poisson equation in an analytical closed-form with the conformal mapping technique. The model is compared with data simulated by TCAD Sentaurus for channel lengths down to 22nm and is in good agreement to this simulation results.
Autors: Mike, Schwarz , Michaela, Weidemann , Alexander, Kloes , Benjamn, Iguez
Appeared in: Solid-State Electronics
Publication date: Jun 2010
Publisher: Elsevier B.V.
 
» 3-D Augmented Reality for MRI-Guided Surgery Using Integral Videography Autostereoscopic Image Overlay
Abstract:
A 3-D augmented reality navigation system using autostereoscopic images was developed for MRI-guided surgery. The 3-D images are created by employing an animated autostereoscopic image, integral videography (IV), which provides geometrically accurate 3-D spatial images and reproduces motion parallax without using any supplementary eyeglasses or tracking devices. The spatially projected 3-D images are superimposed onto the surgical area and viewed via a half-slivered mirror. A fast and accurate spatial image registration method was developed for intraoperative IV image-guided therapy. Preliminary experiments showed that the total system error in patient-to-image registration was 0.90  0.21 mm, and the procedure time for guiding a needle toward a target was shortened by 75%. An animal experiment was also conducted to evaluate the performance of the system. The feasibility studies showed that augmented reality of the image overlay system could increase the surgical instrument placement accuracy and reduce the procedure time as a result of intuitive 3-D viewing.
Autors: Liao, H.;Inomata, T.;Sakuma, I.;Dohi, T.;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Jun 2010, volume: 57, issue:6, pages: 1476 - 1486
Publisher: IEEE
 
» 3-D Sensitivity Function of Shielded Reader by Reciprocity Principle
Abstract:
The sensitivity function to recognize the gapped or shielded reader structure is critical for quantitative analysis of the readback waveform. Although the 3-D finite-element method (FEM) model can capture the full features of geometry and material properties of the reader, it is still preferred to have the precise analytical model as a fast tool for reader design and optimization. This work proposes an analytical model to describe the readback sensitivity function of a shielded reader by the reciprocity principle whereby the media flux absorptions by the sensor free layer and shields are based on the magnetic fields generated when they are treated as the writing elements. Using this approach, the reader geometry and also the material properties of shields and free layer can be included in the model. The proposed 3-D sensitivity function of the model allows us to examine the criteria for read head design and evaluate the reading performance through the analysis of readback waveforms.
Autors: Yuan, Z.-M.;Ong, C. L.;Leong, S. H.;Zhou, T.;Liu, B.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jun 2010, volume: 46, issue:6, pages: 1929 - 1932
Publisher: IEEE
 
» 3-D Visualization of Acute RF Ablation Lesions Using MRI for the Simultaneous Determination of the Patterns of Necrosis and Edema
Abstract:
Catheter ablation using RF energy is a common treatment for atrial arrhythmias. Although this treatment provides a potential cure, currently, there remains a high proportion of patients returning for repeat ablations. Electrophysiologists have little information to verify that a lesion has been created in the myocardium. Temporary electrical block can be created from edema, which will subside. MRI can visualize acute and chronic ablation lesions using delayed-enhancement techniques. However, the ablation patterns cannot be determined from 2-D images alone. Using the combination of -weighted and delayed-enhancement MRI, ablation lesions can be characterized in terms of necrosis and edema. A novel 3-D visualization technique is presented that projects the image intensity due the lesions onto a 3-D cardiac surface, allowing the complete, simultaneous visualization of the delayed-enhancement and -weighted ablation patterns. Results show successful visualization of ablation patterns in 18 patients, and an application of this technique is presented in which electroanatomical mapping systems can be validated by overlaying the acquired ablation points onto the cardiac surfaces and assessing the correlation with the lesion maps.
Autors: Knowles, B. R.;Caulfield, D. R.;Cooklin, M. R.;Rinaldi, C. C.;Gill, J. C.;Bostock, J. C.;Razavi, R. C.;Schaeffter, T. C.;Rhode, K. S.;
Appeared in: IEEE Transactions on Biomedical Engineering
Publication date: Jun 2010, volume: 57, issue:6, pages: 1467 - 1475
Publisher: IEEE
 
» 3-Dimensional Stress Analysis of Virial-Limit Coils
Abstract:
We computed the virial-limit coils which level the distribution of electromagnetic stress with a uniaxial model and a finite element method model. The model's helical pitch number, , the aspect ratio, , and the number of coils was 8. In order to compare with other coil windings, we analysed additional two model coils whose aspect ratios are 1.68 and 3.0 with the same pitch number and the number of coils. We confirmed that VLCs achieve nearly uniform stress distribution from both analyses. And we found that large bending stress is generated in coils from FEM analysis. Distribution of bending stress was found to be different depending on the aspect ratio. The strain in the thickness direction is predominant with a lower aspect ratio while the strain in the width direction is largest with large one.
Autors: Habuchi, T.;Tsutsui, H.;Tsuji-Iio, S.;Shimada, R.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 1924 - 1927
Publisher: IEEE
 
» 30 GHz CMOS Self-Oscillating Mixer for Self-Heterodyne Receiver Application
Abstract:
A 30 GHz CMOS-based self-oscillating mixer (SOM) is demonstrated for millimeter-wave self-heterodyne receiver applications. When injection-locked by transmitted LO carrier, the SOM provides constant and sufficient LO power for mixing process independent of transmitted LO power level. The SOM based on the cross-coupled VCO architecture is realized in 0.13 CMOS process. It has down-conversion loss of about 30 dB and requires the minimum LO injection power of 32 dBm.
Autors: Kim, J.-Y.;Choi, W.-Y.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jun 2010, volume: 20, issue:6, pages: 334 - 336
Publisher: IEEE
 
» 3D CFD computations of transitional flows using DES and a correlation based transition model
Abstract:
The present article describes the application of the correlation based transition model of Menter et al. in combination with the Detached Eddy Simulation (DES) methodology to two cases with large degree of flow separation typically considered difficult to compute. Firstly, the flow is computed over a circular cylinder from Re = 10 to 1 106 reproducing the cylinder drag crisis. The computations show good quantitative and qualitative agreement with the behaviour seen in experiments. This case shows that the methodology performs smoothly from the laminar cases at low Re to the turbulent cases at high Re. Secondly, the flow is computed over a thick airfoil at high angle of attack, in this case the DU-96-W351 is considered. These computations show that a transition model is needed to obtain correct drag predictions at low angle of attack, and that the combination of transition and the DES method improve agreement in the deep stall region. Copyright 2010 John Wiley & Sons, Ltd.
Autors: Niels N. Srensen, A. Bechmann, F. Zahle
Appeared in: Wind Energy
Publication date: Jun 2010
Publisher: Wiley InterScience
 
» 3D-objecttracking with a mixed omnidirectional stereo camera system
Abstract:
This paper presents a novel technique of stereo vision based on the combination of an omnidirectional camera and a perspective camera. The technique combines the 360 field of view of the omnidirectional camera with the long field of view of a perspective camera. We describe the setup of such a camera system and how it can be used to achieve 3D-position estimates. Furthermore, we develop a maximum likelihood approach and a Bayesian approach that are able to fuse monocular and binocular observations of the same object to estimate its position and movement and show how this technique can be applied...
Autors: Martin, Lauer , Miriam, Schnbein , Sascha, Lange , Stefan, Welker
Appeared in: Mechatronics
Publication date: Jun 2010
Publisher: Elsevier B.V.
 
» 5-GHz-Band Vehicle-to-Vehicle Channels: Models for Multiple Values of Channel Bandwidth
Abstract:
In Sen and Matolak's earlier paper, 5-GHz-band vehicle-to-vehicle (V2V) channel models were presented for channel bandwidths of 5 and 10 MHz. In this paper, we provide additional tapped delay line models for bandwidths of 1, 20, 33.33, and 50 MHz based upon the data used in Sen and Matolak's paper. We provide tables of channel parameters for five types of V2V channel classes and also include example tap correlation coefficients. Root-mean-square delay spread values are summarized, as are values of bandwidth for which the channel frequency correlation takes values of 0.7 and 0.5. As with the results from Sen and Matolak's paper, these models should be useful for designers in future V2V communication systems.
Autors: Wu, Q.;Matolak, D. W.;Sen, I.;
Appeared in: IEEE Transactions on Vehicular Technology
Publication date: Jun 2010, volume: 59, issue:5, pages: 2620 - 2625
Publisher: IEEE
 
» 60 GHz Aperture-Coupled Dielectric Resonator Antennas Fed by a Half-Mode Substrate Integrated Waveguide
Abstract:
Dielectric resonator antennas (DRAs) fed by a half-mode substrate integrated waveguide (HMSIW) are proposed and studied in this paper. The investigated antenna configuration consists of a dielectric resonator (DR) mounted on the conducting back plane of an HMSIW. Energy is coupled from the interior HMSIW to the DR through an aperture between them. Using this excitation scheme, a 60 GHz linearly polarized HMSIW-fed DRA is first designed by applying a transverse rectangular slot to feed a dielectric cylinder. This design experimentally exhibits a bandwidth of 24.2% for . In particular, a gain higher than 5.5 dB and a radiation efficiency between 80% and 92% are obtained over the whole operation band, indicating that the HMSIW can be an efficient feed for DRAs operating around 60 GHz. In addition to this linearly polarized example, a DRA of circular polarization, coupled through a pair of cross slots, is also designed, presenting a measured 3-dB axial ratio bandwidth of 4.0%.
Autors: Lai, Q.;Fumeaux, C.;Hong, W.;Vahldieck, R.;
Appeared in: IEEE Transactions on Antennas and Propagation
Publication date: Jun 2010, volume: 58, issue:6, pages: 1856 - 1864
Publisher: IEEE
 
» 60-GHz Ultra-Wideband Radio-Over-Fiber System Using a Novel Photonic Monocycle Generation
Abstract:
An impulse-radio ultra-wideband (UWB) photonic generation system targeting high user density in-flight communications with simultaneous ranging capabilities in the 60-GHz radio band is proposed and demonstrated experimentally and the implementation cost is analyzed. Impulse-radio UWB monocycles are employed for signaling. The monocycles are generated employing a pulsed laser and a differential photoreceiver with phase shifting. Optical frequency up-conversion is performed employing a low-frequency RF carrier and a Mach–Zehnder electrooptical modulator operating in the nonlinear regime. In the experiment, Gaussian monocycles at a 1.244-Gbit/s data rate with 3.8-GHz bandwidth are generated and up-converted to 57 GHz. The performance of the 57-GHz UWB signal after the transmission over a standard single-mode fiber at in-cabin distances up to 100 m is studied. The experimental results show that good quality UWB pulses can be obtained with the proposed system. The impact of the system parameters on performance including wireless transmission and associated cost is analyzed, indicating that a high number of UWB access nodes can be cost-effectively supported by the proposed system.
Autors: Beltran, M.;Llorente, R.;
Appeared in: IEEE Transactions on Microwave Theory and Techniques
Publication date: Jun 2010, volume: 58, issue:6, pages: 1609 - 1620
Publisher: IEEE
 
» 60-MHz PMN-PT Single Crystal Transducers for Microfluidic Analysis Systems
Abstract:
This paper describes the design, fabrication and evaluation of high frequency ultrasonic needle transducers for microfluidic analysis system. The transducers with an aperture size of 0.4mm have been fabricated using lead magnesium niobate-lead titanate (PMN-PT) single crystal as the active piezoelectric element. The PMN-PT has been bonded to a conductive epoxy backing and fixed within a stainless-steel needle housing. A parylene front-face matching layer has been formed by vapor deposition. The measured center frequency and -6dB bandwidth of the PMN-PT transducer are 60MHz and 36%, respectively. The two-way insertion loss is -15.8dB. Such devices are successfully built into a microfluidic...
Autors: S.T., Lau , L.B., Zhao , H.L.W., Chan , H.S., Luo
Appeared in: Sensors and Actuators A: Physical
Publication date: Jun 2010
Publisher: Elsevier B.V.
 
» 70% Efficient Relativistic Magnetron With Axial Extraction of Radiation Through a Horn Antenna
Abstract:
At the Nagaoka University of Technology (Japan), Daimon and Jiang used particle-in-cell (PIC) code simulations to demonstrate that the electronic efficiency of the A6 magnetron with axial extraction can be increased from 3% up to 37% applying different diffraction outputs, from tapered cavities in a conical horn antenna to modified expanded ones that improve magnetron matching with the antenna. This paper presents PIC code simulation results for the modified magnetron design using a transparent cathode, in contrast with Daimon and Jiang's simulations that used a solid explosive emission cathode. Furthermore, by further optimizing the magnetron parameters, we demonstrate an efficiency approaching 70% with gigawatt radiation power for an applied voltage of 400 kV. By maintaining a synchronous interaction of electrons with the operating wave, we found that the radiation power increases as the square of the diode voltage up to a diode voltage of 800 kV with short rise time that does not exceed 20 ns. In addition, we show that using a transparent cathode promotes avoiding the regime of hard excitation of magnetrons.
Autors: Fuks, M. I.;Schamiloglu, E.;
Appeared in: IEEE Transactions on Plasma Science
Publication date: Jun 2010, volume: 38, issue:6, pages: 1302 - 1312
Publisher: IEEE
 
» 8 T Cryogen Free Magnet With a Variable Temperature Insert Using a Heat Switch
Abstract:
The paper presents design and test results for a conduction cooled 8 T superconducting magnetic system with a variable temperature insert for electrical measurements. The system is based on one Pulse Tube cryocooler. The helium gas gap heat switch is used as controllable thermal link between variable temperature chamber and the 4 K stage to avoid overheating of the magnet at high temperatures of the insert. The superconducting magnet is manufactured from NbTi wire and impregnated with epoxy resin by “wet” technology. The clear diameter of variable temperature chamber is 20 mm. The system provides sample temperature range of 5.4–300 K. The maximum operating magnetic field depends on the temperature of the insert and belongs to the range of 7.1–8.2 T. The cool down time of the magnet from room temperature to 3.6 K is 6 hours.
Autors: Demikhov, E.;Kostrov, E.;Lysenko, V.;Piskunov, N.;Troitskiy, V.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 612 - 615
Publisher: IEEE
 
» In Situ Electron Microscopy Mechanical Testing of Silicon Nanowires Using Electrostatically Actuated Tensile Stages
Abstract:
Two types of electrostatically actuated tensile stages for in situ electron microscopy mechanical testing of 1-D nanostructures were designed, microfabricated, and tested. Testing was carried out for mechanical characterization of silicon nanowires (SiNWs). The bulk micromachined stages consist of a comb-drive actuator and either a differential capacitive sensor or a clamped–clamped beam force sensor. High-aspect-ratio structures were designed to increase the driving force of the geometrically optimized actuator and the sensitivity of the capacitive sensor. The actuator stiffness is kept low to enable high tensile force to be exerted in the specimen rather than in the suspensions of the comb drive. Individual SiNWs were mounted on the devices by in situ scanning electron microscopy nanomanipulation, and their tensile properties were determined to demonstrate the device capability. The phosphorus-doped SiNWs, which were grown in a bottom–up manner by the vapor–liquid–solid process, show an average Young's modulus of (170.0 2.4) GPa and a tensile strength of at least 4.2 GPa. Top–down electroless chemically etched SiNWs, with their long axis along the [100] direction, show a fracture strength of 5.4 GPa. [2009-0309]
Autors: Zhang, D.;Breguet, J.-M.;Clavel, R.;Sivakov, V.;Christiansen, S.;Michler, J.;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Jun 2010, volume: 19, issue:3, pages: 663 - 674
Publisher: IEEE
 
» In Vivo Virtual Biopsy of Human Skin by Using Noninvasive Higher Harmonic Generation Microscopy
Abstract:
Higher harmonic generation microscopy (HHGM), combining both second- and third-harmonic generation (SHG and THG) modalities, is a new paradigm for in vivo noninvasive virtual biopsy. With the ability to achieve noninvasiveness, high resolution, and high penetrability at the same time, HHGM is a promising tool for future noninvasive diagnosis of skin diseases. In this paper, we report our preliminary pilot clinical trial results on in vivo virtual biopsy of human skin by using HHGM. In vivo virtual biopsy imaging has been performed on 21 volunteers’ inside and outside forearm skin along with the damage evaluation. Together with an embryo viability study, our results not only indicate a superior viability performance of the developed system, but also a much improved penetrability in different skin types. Ex vivo studies further confirm the capability of the developed virtual biopsy system to pathohistologically distinguish different skin diseases. Our in vivo HHGM biopsy study of human skin with different colors also reveals the central role of melanin in the epi-THG resonance enhancement and attenuation. With a unique capability to molecular image the melanin distribution, epi-THG microscopy is also highly valuable for diagnosing and screening early melanocytic lesions.
Autors: Chen, S.-Y.;Chen, S.-U.;Wu, H.-Y.;Lee, W.-J.;Liao, Y.-H.;Sun, C.;
Appeared in: IEEE Journal of Selected Topics in Quantum Electronics
Publication date: Jun 2010, volume: 16, issue:3, pages: 478 - 492
Publisher: IEEE
 
» In-Vivo Dosimetry for Photon Radiotherapy Based on Pair Production
Abstract:
Experience during percutaneous ion beam therapy at Gesellschaft für Schwerionenforschung showed that the treatment can be improved by in-vivo dose monitoring that is independent of the irradiation device and based on positron emission tomography. It has been studied whether a similar technique can be implemented for high energy photon therapy. Simulation shows that the dose is closely related to the distribution of the annihilation points of positrons emerging from pair production. Design parameters of a detector system have been assessed which is capable of registering annihilation radiation during treatment. A test system has been assembled which can be operated with various scintillator crystals and avalanche photodiodes. A custom digital signal processing system has been implemented. Phantom experiments at a clinical linear accelerator disclosed a severe background that does not solely stem from scattered primary photons but from radiation directly emitted from the treatment head. It was not possible to shield the detectors sufficiently and thus there was no success in identifying annihilation radiation.
Autors: Kormoll, T.;Kunath, D.;Enghardt, W.;
Appeared in: IEEE Transactions on Nuclear Science
Publication date: Jun 2010, volume: 57, issue:3, pages: 1125 - 1131
Publisher: IEEE
 
» Ni and Zn doped MgTiO3 thin films: Structure, microstructure, and dielectric characteristics
Abstract:
The addition of low loss ilmenite impurities, can effectively tailor the dielectric properties of MgTiO3 without modifying the crystal structure. In the present study, the modification of the structural and dielectric properties of sol gel derived MgTiO3 films by doping with Ni and Zn is exploited. The change of the dielectric response and unit cell parameters of doped MgTiO3 is correlated with Ni and Zn occupancy. The temperature stability of MgTiO3 thin films is improved with doping, while the dielectric losses are aggravated with both Zn and Ni doping, which is correlated with the localized d electrons of the dopant cations. The dielectric permittivity decreased with Ni doping while it increased with Zn, which is attributed to the lower ionic polarizability of Ni2+ (1.23 Å3) as in comparison with Mg2+ (1.32 Å3) while Zn2+ has a higher ionic polarizability (2.04 Å3).
Autors: Surendran, Kuzhichalil P.;Wu, Aiying;Vilarinho, Paula M.;Ferreira, Victor M.;
Appeared in: Journal of Applied Physics
Publication date: Jun 2010, volume: 107, issue:11, pages: 114112 - 114112-8
Publisher: IEEE
 
» TiO2 nanotubes as a cold cathode for x-ray generation
Abstract:
Here we report on an x-ray source based on titanium dioxide (TiO2) nanotubes grown by electrochemical oxidation. From the analysis of current-voltage characteristics of TiO2 electron emitter field emission nature of the current was confirmed. The threshold voltage and field enhancement factors were derived to be ∼1.8 Vm and ∼8363, respectively. The current density was ∼4.0 mA/cm2 at ∼2.4 Vm. The stability tests showed that the current stayed stable within 6% for more than 720 h. TiO2 nanotubes were used as a cold cathode in x-ray tube and it was demonstrated that TiO2 nanotubes could be a good candidate for such applications.
Autors: Alivov, Yahya;Klopfer, Michael;Molloi, Sabee;
Appeared in: Applied Physics Letters
Publication date: Jun 2010, volume: 96, issue:24, pages: 243502 - 243502-3
Publisher: IEEE
 
» 85Rb tunable-interaction Bose–Einstein condensate machine
Abstract:
We describe our experimental setup for creating stable Bose–Einstein condensates (BECs) of 85Rb with tunable interparticle interactions. We use sympathetic cooling with 87Rb in two stages, initially in a tight Ioffe–Pritchard magnetic trap and subsequently in a weak, large-volume, crossed optical dipole trap, using the 155 G Feshbach resonance to manipulate the elastic and inelastic scattering properties of the 85Rb atoms. Typical 85Rb condensates contain 4×104 atoms with a scattering length of a=+200a0. Many aspects of the design presented here could be adapted to other dual-species BEC machines, including those involving degenerate Fermi–Bose mixtures. Our minimalist apparatus is well suited to experiments on dual-species and spinor Rb condensates, and has several simplifications over the 85Rb BEC machine at JILA, which we discuss at the end of this article.
Autors: Altin, P. A.;Robins, N. P.;Doring, D.;Debs, J. E.;Poldy, R.;Figl, C.;Close, J. D.;
Appeared in: Review of Scientific Instruments
Publication date: Jun 2010, volume: 81, issue:6, pages: 063103 - 063103-9
Publisher: IEEE
 
» Noise of Silicon Nanowire BioFETs
Abstract:
The noise of silicon nanowire (NW) biological field-effect transistors (NW FETs with exposed channels) is characterized and compared with various fabrication approaches, specifically, a wet orientation-dependent etch (ODE) versus common plasma-based etching methods. The wet-etched devices are shown to have significantly lower noise and subthreshold swing, and the average extracted Hooge parameter for ODE wet-etched devices is comparable to the values reported for submicrometer MOSFETs with a gate stack.
Autors: Rajan, N. K.;Routenberg, D. A.;Chen, J.;Reed, M. A.;
Appeared in: IEEE Electron Device Letters
Publication date: Jun 2010, volume: 31, issue:6, pages: 615 - 617
Publisher: IEEE
 
» Phase CoPt-TiO /FePt-TiO Exchange Coupled Media With Small Switching Field
Abstract:
The effects of CoPt-TiO /FePt-TiO bilayer and (Co Fe ) Pt -TiO ( at.%) multilayer exchange coupled media on switching field and magnetization reversal mechanism were studied. Results showed that both bilayer and multilayer exchange coupled media with out-of-plane anisotropy in the hard and soft layers were effective to reduce the switching field of single layer FePt-TiO media. First order reversal curve (FORC) distribution indicated that switching field distribution in the bilayer and multilayer exchanged coupled media was significantly narrowed down compared to the single layer and magnetization reversal was ascribed to domain formation followed by domain wall motion.
Autors: Pandey, K. K. M.;Chen, J. S.;Chow, G. M.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jun 2010, volume: 46, issue:6, pages: 1955 - 1958
Publisher: IEEE
 
» Coils for MRI Applications
Abstract:
In this paper, we report our progress in the development of a low cost, liquid-helium-free superconducting MRI magnet. Several technical issues related to the construction of such a magnet to operate in persistent current mode are discussed, namely, the performance consistency of long length conductors, the fabrication of superconducting joints and persistent current switches. Quench detection and protection of such magnets operated in solid nitrogen environment are also discussed.
Autors: Yao, W.;Bascunan, J.;Hahn, S.;Iwasa, Y.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 756 - 759
Publisher: IEEE
 
» Strand Characterization for the Nijmegen 45 T Hybrid Magnet
Abstract:
The Nijmegen 45 T hybrid magnet will consist of an inner resistive 33 T resistive magnet and a superconducting 12 T outsert magnet. In the present conceptual design of the layer-wound outsert, the conductor is a Cable-In-Conduit Conductor (CICC) with a stainless steel conduit, operating at 4.5 K by a forced flow of supercritical helium. At nominal magnetic field, the operating current is 12.3 kA.
Autors: den Ouden, A.;Wiegers, S. A. J.;Perenboom, J. A. A. J.;Wessel, W. A. J.;ten Kate, H. H. J.;Maan, J. C.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 1383 - 1386
Publisher: IEEE
 
» Coil Options for Fusion Poloidal Magnets
Abstract:
A hybrid solution is proposed for the IGNITOR research fusion machine by using of superconducting coils for some poloidal magnets, in association with high field copper magnets for the central solenoid and for the toroidal field coils. The choice to be made among the various superconductors is based on the materials performances in high magnetic field, on the mechanical strength of the conductors and on the cost of manufacturing large coils. In this study we analyze a coil based on MgB2, a "medium temperature" superconducting material that we expect will avoid, in association with others high temperature superconductors, the use of liquid He in future machines. The external poloidal magnet, 5 m in diameter and subjected to a magnetic field of 5 T, represents a real test bench of the technical issues which should be addressed in the exploitation of the future fusion reactors. To fulfil the technical characteristics of the selected magnet we must optimize the fill factor of the superconducting MgB2 wires, increasing the presently obtained 30% value. Accordingly, the effective current density in the superconducting wire should be of about 1500 A/mm2 (@10 K, 5 T), a value which is compatible with the present best MgB2 laboratory short wires, doped by C or SiC.
Autors: Giunchi, G.;Coppi, B.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 1610 - 1613
Publisher: IEEE
 
» FePt/Fe Exchange Coupled Composite Structure on MgO Substrates
Abstract:
A core-shell type exchange-coupled composite (ECC) structure is developed with an L10 phase FePt core and an Fe shell. Coercivity decreases from 30.6 kOe for the FePt granular film with a very thin thickness of 3.2 nm, to 7.85 kOe for the FePt/Fe core-shell type granular film with a 3-nm-thick Fe. The energy barriers of the FePt/Fe films are measured by using Sharrock equation. A modified formula of gain factor considering the effect of films' thickness is proposed. Core-shell type FePt/Fe ECC granular film has a large advantage over a conventional granular film for media application.
Autors: Bin Ma;Hao Wang;Haibao Zhao;Chengjun Sun;Acharya, R.;Jian-Ping Wang;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jun 2010, volume: 46, issue:6, pages: 2345 - 2348
Publisher: IEEE
 
» Phase CoPt-TiO /FePt-TiO Exchange Coupled Media With Small Switching Field
Abstract:
The effects of L10 CoPt-TiO2/FePt-TiO2 bilayer and (CoxFe100-x)50Pt50-TiO2 (0 ¿ x ¿ 100 at.%) multilayer exchange coupled media on switching field and magnetization reversal mechanism were studied. Results showed that both bilayer and multilayer exchange coupled media with out-of-plane anisotropy in the hard and soft layers were effective to reduce the switching field of single layer FePt-TiO2 media. First order reversal curve (FORC) distribution indicated that switching field distribution in the bilayer and multilayer exchanged coupled media was significantly narrowed down compared to the single layer and magnetization reversal was ascribed to domain formation followed by domain wall motion.
Autors: Pandey, K.K.M.;Chen, J.S.;Chow, G.M.;
Appeared in: IEEE Transactions on Magnetics
Publication date: Jun 2010, volume: 46, issue:6, pages: 1955 - 1958
Publisher: IEEE
 
» A 0.18 m CMOS Quadrature VCO Using the Quadruple Push-Push Technique
Abstract:
This letter presents a new quadrature voltage-controlled oscillator (QVCO), which consists of two complementary cross-coupled voltage-controlled oscillators (VCOs) with two tail inductors. The two differential VCOs are coupled via two tail inductors to form a quadrature VCO. The proposed CMOS QVCO has been implemented with the TSMC 0.18 m CMOS technology and the die area is 0.83 0.96 mm . At the supply voltage of 1.45 V, the free-running frequency of the QVCO is tunable from 4.94 to 5.22 GHz as the tuning voltage is varied from 0.0 to 1.0 V. The total power consumption is 8.7 mW and the measured phase noise at 1 MHz frequency offset is dBc/Hz at the oscillation frequency of 5.15 GHz and the figure of merit (FOM) of the proposed QVCO is dBc/Hz.
Autors: Jang, S.-L.;Shih, C.-C.;Liu, C.-C.;Juang, M.-H.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jun 2010, volume: 20, issue:6, pages: 343 - 345
Publisher: IEEE
 
» A 0.93-mA Spur-Enhanced Frequency Synthesizer for L1/L5 Dual-Band GPS/Galileo RF Receiver
Abstract:
A versatile frequency synthesizer for a L1/L5 dual-band GPS/Galilleo dual-mode RF receiver is designed with a 0.13 CMOS process. For spur reduction, a simple low-glitch charge-pump circuit (CPC) is proposed in this letter. The fabricated chip achieves the in-band phase noise of 92 dBc/Hz and the spur performance of 71.23 dBc at 8.184 MHz offset from 1.571 GHz carrier with a second-order loop filter.
Autors: Hwang, I.-C.;Baek, D.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jun 2010, volume: 20, issue:6, pages: 355 - 357
Publisher: IEEE
 
» A 1.3 GHz NMR Magnet Design Under High Hoop Stress Condition
Abstract:
NMR magnets using high- superconductors (HTS) to generate high magnetic fields exceeding 25 T are currently being designed by several organizations. In these designs, the HTS is used for the inner coils, and the other coils consist of NbTi and wires. The YBCO wire, which is a typical HTS, has excellent critical current performance over a wide range of magnetic fields and tolerates high tensile stress of up to 700 MPa. These properties make it possible to realize a high-field NMR magnet. In particular, the superior mechanical strength allows for the high-stress criterion of the electromagnetic force to be applied to the design of the magnets. In this study, we show the conceptual design of 1.3 GHz (30.5 T) NMR magnets under the condition of high hoop stress of 500 MPa. To achieve high magnetic field homogeneity in these designs, we propose three magnet design plans that have different arrangements of the compensation coils. We assumed that the magnet would be operated by the driven mode at 4.2 K. We also considered the strong angular dependence of the critical current of the YBCO wires to design the magnet.
Autors: Otsuka, A.;Kiyoshi, T.;Takeda, M.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 596 - 599
Publisher: IEEE
 
» A 10-bit 100-MS/s Reference-Free SAR ADC in 90 nm CMOS
Abstract:
A 1.2 V 10-bit 100 MS/s Successive Approximation (SA) ADC is presented. The scheme achieves high-speed and low-power operation thanks to the reference-free technique that avoids the static power dissipation of an on-chip reference generator. Moreover, the use of a common-mode based charge recovery switching method reduces the switching energy and improves the conversion linearity. A variable self-timed loop optimizes the reset time of the preamplifier to improve the conversion speed. Measurement results on a 90 nm CMOS prototype operated at 1.2 V supply show 3 mW total power consumption with a peak SNDR of 56.6 dB and a FOM of 77 fJ/conv-step.
Autors: Zhu, Y.;Chan, C.-H.;Chio, U.-F.;Sin, S.-W.;U, S.-P.;Martins, R. P.;Maloberti, F.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Jun 2010, volume: 45, issue:6, pages: 1111 - 1121
Publisher: IEEE
 
» A 12-kVA DSP-Controlled Laboratory Prototype UPQC Capable of Mitigating Unbalance in Source Voltage and Load Current
Abstract:
This paper reports the development of a laboratory prototype of a fully digital DSP-controlled 12-kVA unified power quality conditioner (UPQC), capable of compensating for both the supply voltage and the load current imperfections. A fully digital controller based on the TMS320F2812 DSP platform is implemented for the reference generation as well as control purposes. The delay problem in the digital controller is overcome by application of a fast DSP, a compact control technique and proper flow of control steps in the DSP software. A phase-locked loop-less software grid synchronization method has been implemented for the effective operation of the UPQC under conditions of grid frequency variation. A sequence-based compensation strategy has been developed to compensate for balanced and unbalanced sags while accommodating the fact that the voltage injection capability of the UPQC is limited. The prototype UPQC power circuit, control features, and control algorithm along with experimental results are presented in this paper.
Autors: Axente, I.;Ganesh, J. N.;Basu, M.;Conlon, M. F.;Gaughan, K.;
Appeared in: IEEE Transactions on Power Electronics
Publication date: Jun 2010, volume: 25, issue:6, pages: 1471 - 1479
Publisher: IEEE
 
» A 12.5 GHz-spaced optical frequency comb spanning >400 nm for near-infrared astronomical spectrograph calibration
Abstract:
A 12.5 GHz-spaced optical frequency comb locked to a global positioning system disciplined oscillator for near-infrared (IR) spectrograph calibration is presented. The comb is generated via filtering a 250 MHz-spaced comb. Subsequent nonlinear broadening of the 12.5 GHz comb extends the wavelength range to cover 1380–1820 nm, providing complete coverage over the H-band transmission window of earth’s atmosphere. Finite suppression of spurious sidemodes, optical linewidth, and instability of the comb has been examined to estimate potential wavelength biases in spectrograph calibration. Sidemode suppression varies between 20 and 45 dB, and the optical linewidth is ∼350 kHz at 1550 nm. The comb frequency uncertainty is bounded by ±30 kHz (corresponding to a radial velocity of ±5 cm/s), limited by the global positioning system disciplined oscillator reference. These results indicate that this comb can readily support radial velocity measurements below 1 m/s in the near IR.
Autors: Quinlan, F.;Ycas, G.;Osterman, S.;Diddams, S. A.;
Appeared in: Review of Scientific Instruments
Publication date: Jun 2010, volume: 81, issue:6, pages: 063105 - 063105-9
Publisher: IEEE
 
» A 120 mm Bore Quadrupole for the Phase I LHC Upgrade
Abstract:
The phase I LHC upgrade foresees the installation of a new final focusing for the high luminosity experiences in order to be able to focus the beams in the interaction points to . Key element of this upgrade is a large bore (120 mm) superconducting quadrupole. This article proposes a magnet design that will make use of the LHC main dipole superconducting cable. Due to the schedule constraints and to the budget restrictions, it is mandatory to integrate in the design the maximum number of features successfully used during the LHC construction. This paper presents this design option and the rationales behind the several technical choices.
Autors: Fessia, P.;Granieri, P.;Borgnolutti, F.;Regis, F.;Richter, D.;Todesco, E.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 140 - 143
Publisher: IEEE
 
» A 120-420 MHz delay-locked loop with multi-band voltage-controlled delay unit
Abstract:
A low-jitter and low-power dissipation delay-locked loop (DLL) is presented. A proposed multi-band voltage control delay unit (MVCDU) is employed to extend the operation frequency of the DLL by controlling the delay cell within the MVCDU. The jitter of DLL is reduced due to MVCDU's low sensitivity. The delay cell in the MVCDU employs a differential configuration to further reduce the noise impact from the fluctuation in the supply and ground voltage. The operating frequency of the proposed DLL ranges from 120 to 420 MHz. The proposed design has been fabricated in a TSMC 0.18m CMOS process. The measured RMS and peak-to-peak jitters are 4.86 and 34.55 ps, respectively, at an operating frequency of 300 MHz. The power dissipation is below 14.85 mW at an operating frequency of 420 MHz. Copyright 2010 John Wiley & Sons, Ltd.
Autors: Ko-Chi Kuo, Yi-Hsi Hsu
Appeared in: International Journal of Circuit Theory and Applications
Publication date: Jun 2010
Publisher: Wiley InterScience
 
» A 2 2 MIMO DVB-T2 System: Design, New Channel Estimation Scheme and Measurements With Polarization Diversity
Abstract:
The increasing interest in MIMO (Multiple-Input Multiple-Output) systems has given rise to a prolific research activity in recent years. Both theoretical and practical issues have been studied. However, so far few MIMO testbeds or prototypes have been built for DVB-T or future standards. In this paper, a novel 2 2 MIMO testbed specifically designed for evaluating the performances of a DVB-T2 MIMO system is presented. The description of signal processing is detailed including a new scheme to estimate the MIMO channel matrix. Finally, measurement results with different polarization schemes are presented for typical scenarios, obtaining higher capacity in LoS situations using polarization diversity.
Autors: Gomez-Calero, C.;Navarrete, L. C.;de Haro, L.;Martinez, R.;
Appeared in: IEEE Transactions on Broadcasting
Publication date: Jun 2010, volume: 56, issue:2, pages: 184 - 192
Publisher: IEEE
 
» A 2-Dimensional Finite-Element Method for Transient Magnetic Field Computation Taking Into Account Parasitic Capacitive Effects
Abstract:
A formulation to model solid conductor groups in transient finite-element model (FEM) of inverter driven motor drives is presented to facilitate the users to model many solid conductors in one winding. A novel two-dimensional (2-D) FEM formulation which can include the displacement current in the direction of the model's depth is deduced. The effect of displacement current in the plane of the solution domain is represented by coupling the circuit of capacitances into the FEM equations. By introducing additional unknowns, the last set of the system equations has a symmetrical coefficient matrix. A method using electric charge as an excitation to compute the capacitance matrix is also presented to reduce the computation time. The developed algorithm has been applied to evaluate the effect of a LC filter in a converter motor drive and the parasitic capacitive effect is included.
Autors: Fu, W. N.;Ho, S. L.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 1869 - 1873
Publisher: IEEE
 
» A 2.1 to 6 GHz Tunable-band LNA With Adaptive Frequency Responses by Transistor Size Scaling
Abstract:
A 2.1 to 6 GHz tunable-band LNA by using transistor-size scaling technique is realized in 90 nm CMOS technology, which adopts a scalable-size transistor mimicked by the parallel-connected transistors with binary weighted device sizes. In the 16 programmable bands located in the frequencies of interest, the S21 varies in the range from 15.1 to 16.9 dB, and the NF is from 2.16 to 2.81 dB. This tunable -band LNA occupies only , which is readily compact compared with the prior arts of passive components switchable LNAs.
Autors: Wang, Y.-H.;Lin, K.-T.;Wang, T.;Chiu, H.-W.;Chen, H.-C.;Lu, S.-S.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jun 2010, volume: 20, issue:6, pages: 346 - 348
Publisher: IEEE
 
» A 2.4-GS/s FFT Processor for OFDM-Based WPAN Applications
Abstract:
This brief presents a fast Fourier transform (FFT) processor that provides high throughput rate (T.R.) by applying the eight-data-path pipelined approach for wireless personal area network applications. The hardware costs, including the power consumption and area, increase due to multiple data paths and increased wordlength along stages. To resolve these issues, a novel simplification method to reduce the hardware cost in multiplication units of the multiple-path FFT approach is proposed. A multidata scaling scheme to reduce wordlengths while preserving the signal-to-quantization-noise ratio is also presented. Using UMC 90-nm 1P9M technology, a 2048-point FFT processor test chip has been designed, and its 128-point FFT kernel has been fabricated for ultrawideband (UWB) applications and also for verification. The 2048-point FFT processor can provide a T.R. of 2.4 GS/s at 300 MHz with a power consumption of 159 mW. Compared with the four-data-path approach, a power consumption saving of about 30% can be achieved under the same T.R. In addition, the 128-point FFT kernel test chip has a measured power consumption of 6.8 mW with a T.R. of 409.6 MS/s at 52 MHz to meet the UWB standard with a saving in power consumption of about 40%.
Autors: Tang, S.-N.;Tsai, J.-W.;Chang, T.-Y.;
Appeared in: IEEE Transactions on Circuits and Systems II: Express Briefs
Publication date: Jun 2010, volume: 57, issue:6, pages: 451 - 455
Publisher: IEEE
 
» A 3 Tesla Superconducting Magnet for Hall Sensor Calibration
Abstract:
A 3 T superconducting magnet with a 70 mm diameter warm bore and energy storage of 47 kJ has been successfully fabricated and tested, which can be used to calibrate Hall sensors in high magnetic field as well as conduct superconducting experiments. The magnet consists of three solenoid coils and an iron yoke. The homogeneity of the magnetic field in the region of interest (ROI) is . The coils of the magnet were fabricated with NbTi-Cu superconducting wire and the stray magnetic field is shielded by an iron yoke. The coils and yoke are fully immersed in a helium vessel. The optimized structural design, stress and quench simulation, fabrication and test results are presented in this paper.
Autors: Guo, B.;Ma, L.;Li, Q.;Wu, W.;Yao, Q.;Zhang, X.;Wu, X.;He, Y.;Han, S.;Zhang, S.;Yuan, P.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 1781 - 1784
Publisher: IEEE
 
» A 3-D Cache With Ultra-Wide Data Bus for 3-D Processor-Memory Integration
Abstract:
Slow cache memory systems and low memory bandwidth present a major bottleneck in performance of modern microprocessors. 3-D integration of processor and memory subsystems provides a means to realize a wide data bus that could provide a high bandwidth and low latency on-chip cache. This paper presents a three-tier, 3-D 192-kB cache for a 3-D processor-memory stack. The chip is designed and fabricated in a 0.18 m fully depleted SOI CMOS process. An ultra wide data bus for connecting the 3-D cache with the microprocessor is implemented using dense vertical vias between the stacked wafers. The fabricated cache operates at 500 MHz and achieves up to 96 GB/s aggregate bandwidth at the output.
Autors: Zia, A.;Jacob, P.;Kim, J.-W.;Chu, M.;Kraft, R. P.;McDonald, J. F.;
Appeared in: IEEE Transactions on Very Large Scale Integration Systems
Publication date: Jun 2010, volume: 18, issue:6, pages: 967 - 977
Publisher: IEEE
 
» A 40 T Hybrid Magnet Under Construction in China
Abstract:
The Chinese National Project to develop new high magnetic field facilities began in 2008. It includes the construction of a 40 T hybrid magnet. The magnet will be built at the Chinese High Magnetic Field Laboratory (CHMFL) of the Chinese Academy of Sciences. It consists of a superconducting outsert magnet and a resistive insert magnet. The outsert magnet with a bore diameter of 580 mm at room temperature is expected to provide 11 T. It is composed of two coils: the inner coil is made of cable-in-conduit-conductor (CICC), the outer coil of NbTi CICC. The insert magnet, which will be a 20 MW Florida-Bitter-type resistive magnet with a clear bore diameter of 32 mm, will produce 29 T. The construction of the hybrid magnet is scheduled to be completed in 2013.
Autors: Kuang, G.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 680 - 683
Publisher: IEEE
 
» A 5-Gb/s ADC-Based Feed-Forward CDR in 65 nm CMOS
Abstract:
This paper presents an ADC-based CDR that blindly samples the received signal at twice the data rate and uses these samples to directly estimate the locations of zero crossings for the purpose of clock and data recovery. We successfully confirmed the operation of the proposed CDR architecture at 5 Gb/s. The receiver is implemented in 65 nm CMOS, occupies 0.51 mm , and consumes 178.4 mW at 5 Gb/s.
Autors: Tyshchenko, O.;Sheikholeslami, A.;Tamura, H.;Kibune, M.;Yamaguchi, H.;Ogawa, J.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Jun 2010, volume: 45, issue:6, pages: 1091 - 1098
Publisher: IEEE
 
» A 5.8 GHz Low-Phase-Noise LC-QVCO Using Splitting Switched Biasing Technique
Abstract:
A 5.8 GHz LC-tank quadrature voltage-controlled oscillator (QVCO) is proposed for achieving low phase noise. Phase noise contributed by the tank voltage amplitude and the 1/f noise of the tail transistors were simultaneously improved when the splitting switched biasing technique was adopted. Measured results showed a tuning range from 5.09 to 6.15 GHz, a phase noise of at an offset of 1 MHz, and a phase-noise figure-of-merit of , while consuming 3.06 mA for the core QVCO from a 1.6 V supply. The proposed QVCO was designed using a CMOS process.
Autors: Kim, K.-W.;Chang, H.-J.;Kim, Y.-M.;Yun, T.-Y.;
Appeared in: IEEE Microwave and Wireless Components Letters
Publication date: Jun 2010, volume: 20, issue:6, pages: 337 - 339
Publisher: IEEE
 
» A 500 mW ADC-Based CMOS AFE With Digital Calibration for 10 Gb/s Serial Links Over KR-Backplane and Multimode Fiber
Abstract:
This paper presents the design of an analog-front-end (AFE) integrated into a DSP-based transceiver for both serial 10 Gbps KR-backplane and long-reach-multimode-fiber (LRM) applications. The receiver consists of a programmable gain amplifier (PGA) and a 6-bit 4-way time-interleaved ADC, which is digitally calibrated to compensate for the offset, gain and phase mismatches between the interleaved channels. With a 5 GHz input signal, the ADC achieves overall SNDR of 29 dB, while the measured SNDR of flash sub-ADC is 31.6 dB. The power efficiency FoM of the complete interleaved ADC is 1.4 pJ per conversion step. The PLL uses a calibrated LC-VCO and the TX features a full-rate 3-tap de-emphasis at the output. Inductively tuned buffers connected in tandem are employed to distribute the 10 GHz clock. Random and deterministic jitter measured at the TX output are 0.38 and 2.65 , respectively. Implemented in 65 nm CMOS technology, the AFE occupies an area of 3 and consumes 500 mW from a 1 V supply. BER of less than 10 is measured over legacy backplanes with 26 dB loss at Nyquist and the measured transceiver optical sensitivity is less than for all four LRM stressors, exceeding both the KR and the LRM specifications.
Autors: Cao, J.;Zhang, B.;Singh, U.;Cui, D.;Vasani, A.;Garg, A.;Zhang, W.;Kocaman, N.;Pi, D.;Raghavan, B.;Pan, H.;Fujimori, I.;Momtaz, A.;
Appeared in: IEEE Journal of Solid-State Circuits
Publication date: Jun 2010, volume: 45, issue:6, pages: 1172 - 1185
Publisher: IEEE
 
» A -Based, Model Superconducting Helical Undulator Fabricated Using a Wind and React Process
Abstract:
A model helical undulator 250 mm in length, with a period of 14 mm, was designed, fabricated and tested. The helical coil was wound with multifilamentary, internal-Sn type strand. The 0.7 mm OD strand was insulated with S-glass, wound onto the former, and reacted, after which the coil underwent vacuum epoxy impregnation. The beam aperture was 7 mm, the winding bore diameter was 8 mm, and the OD of the complete winding was 18 mm. The helical poles were made from 1016 low carbon steel, and projected slightly above the coil pack, with an OD of 19.06 mm. The coil and the magnetic field in the bore were measured at 4.2 K in a liquid helium bath. The bore field was also measured as a function of position along the length of the undulator.
Autors: Majoros, M.;Sumption, M. D.;Susner, M. A.;Bhartiya, S.;Mahmud, M.;Collings, E. W.;Tomsic, M.;Rindfleisch, M.;Phillips, J.;Lyons, D.;Yue, J.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 270 - 273
Publisher: IEEE
 
» A -Based, Model Superconducting Helical Undulator Fabricated Using a Wind and React Process
Abstract:
A model helical undulator 250 mm in length, with a period of 14 mm, was designed, fabricated and tested. The helical coil was wound with multifilamentary, internal-Sn type Nba3Sn strand. The 0.7 mm OD strand was insulated with S-glass, wound onto the former, and reacted, after which the coil underwent vacuum epoxy impregnation. The beam aperture was 7 mm, the winding bore diameter was 8 mm, and the OD of the complete winding was 18 mm. The helical poles were made from 1016 low carbon steel, and projected slightly above the coil pack, with an OD of 19.06 mm. The coil Ic and the magnetic field in the bore were measured at 4.2 K in a liquid helium bath. The bore field was also measured as a function of position along the length of the undulator.
Autors: Majoros, M.;Sumption, M.D.;Susner, M.A.;Bhartiya, S.;Mahmud, M.;Collings, E.W.;Tomsic, M.;Rindfleisch, M.;Phillips, J.;Lyons, D.;Yue, J.;
Appeared in: IEEE Transactions on Applied Superconductivity
Publication date: Jun 2010, volume: 20, issue:3, pages: 270 - 273
Publisher: IEEE
 
» A Bayesian Approach to Automated Creation of Tactile Facial Images
Abstract:
Portrait photos (facial images) play important social and emotional roles in our life. This type of visual media is unfortunately inaccessible by users with visual impairment. This paper proposes a systematic approach for automatically converting human facial images into a tactile form that can be printed on a tactile printer and explored by a user who is blind. We propose a deformable Bayesian Active Shape Model (BASM), which integrates anthropometric priors with shape and appearance information learnt from a face dataset. We design an inference algorithm under this model for processing new face images to create an input-adaptive face sketch. Further, the model is enhanced by input-specific details through semantic-aware processing. We report experiments on evaluating the accuracy of face alignment using the proposed method, with comparison with other state-of-the-art results. Furthermore, subjective evaluations of the produced tactile face images were performed by 17 persons including six visually-impaired users, confirming the effectiveness of the proposed approach in conveying via haptics vital visual information in a face image.
Autors: Wang, Z.;Li, B.;
Appeared in: IEEE Transactions on Multimedia
Publication date: Jun 2010, volume: 12, issue:4, pages: 233 - 246
Publisher: IEEE
 
» A Bayesian Mixture Approach to Modeling Spatial Activation Patterns in Multisite fMRI Data
Abstract:
We propose a probabilistic model for analyzing spatial activation patterns in multiple functional magnetic resonance imaging (fMRI) activation images such as repeated observations on an individual or images from different individuals in a clinical study. Instead of taking the traditional approach of voxel-by-voxel analysis, we directly model the shape of activation patterns by representing each activation cluster in an image as a Gaussian-shaped surface. We assume that there is an unknown true template pattern and that each observed image is a noisy realization of this template. We model an individual image using a mixture of experts model with each component representing a spatial activation cluster. Taking a nonparametric Bayesian approach, we use a hierarchical Dirichlet process to extract common activation clusters from multiple images and estimate the number of such clusters automatically. We further extend the model by adding random effects to the shape parameters to allow for image-specific variation in the activation patterns. Using a Bayesian framework, we learn the shape parameters for both image-level activation patterns and the template for the set of images by sampling from the posterior distribution of the parameters. We demonstrate our model on a dataset collected in a large multisite fMRI study.
Autors: Kim, S.;Smyth, P.;Stern, H.;
Appeared in: IEEE Transactions on Medical Imaging
Publication date: Jun 2010, volume: 29, issue:6, pages: 1260 - 1274
Publisher: IEEE
 
» A BCM Theory of Meta-Plasticity for Online Self-Reorganizing Fuzzy-Associative Learning
Abstract:
Self-organizing neurofuzzy approaches have matured in their online learning of fuzzy-associative structures under time-invariant conditions. To maximize their operative value for online reasoning, these self-sustaining mechanisms must also be able to reorganize fuzzy-associative knowledge in real-time dynamic environments. Hence, it is critical to recognize that they would require self-reorganizational skills to rebuild fluid associative structures when their existing organizations fail to respond well to changing circumstances. In this light, while Hebbian theory (Hebb, 1949) is the basic computational framework for associative learning, it is less attractive for time-variant online learning because it suffers from stability limitations that impedes unlearning. Instead, this paper adopts the Bienenstock–Cooper–Munro (BCM) theory of neurological learning via meta-plasticity principles (Bienenstock et al., 1982) that provides for both online associative and dissociative learning. For almost three decades, BCM theory has been shown to effectively brace physiological evidence of synaptic potentiation (association) and depression (dissociation) into a sound mathematical framework for computational learning. This paper proposes an interpretation of the BCM theory of meta-plasticity for an online self-reorganizing fuzzy-associative learning system to realize online-reasoning capabilities. Experimental findings are twofold: 1) the analysis using S&P-500 stock index illustrated that the self-reorganizing approach could follow the trajectory shifts in the time-variant S&P-500 index for about 60 years, and 2) the benchmark profiles showed that the fuzzy-associative approach yielded comparable results with other fuzzy-precision models with similar online objectives.
Autors: Tan, J.;Quek, C.;
Appeared in: IEEE Transactions on Neural Networks
Publication date: Jun 2010, volume: 21, issue:6, pages: 985 - 1003
Publisher: IEEE
 
» A Bendable-Channel FinFET for Logic Application
Abstract:
Bendable-channel fin field-effect transistor (FET) (FinFET) (BC-FinFET) is presented for the basic logic family that includes nand, nor , and pass gate. The BC-FinFET can replace the suspended-gate FET (SGFET), and its function is very similar to that of a double-gate MOSFET. The BC-FinFET is composed of an n-type and p-type MOSFETs, and hence, it can be applicable for logic circuits. Numerical simulations based on elementary characteristics extracted from the fabricated BC-FinFET have been carried out for nand and nor circuits from an input–output characteristics' point of view. The proposed architecture can improve the standby and dynamic power consumption by reduction of the number of SGFETs and the size of the chip, while improving circuit performance.
Autors: Kwon, S.-G.;Han, J.-W.;Choi, Y.-K.;
Appeared in: IEEE Electron Device Letters
Publication date: Jun 2010, volume: 31, issue:6, pages: 624 - 626
Publisher: IEEE
 
» A Bibliographic Analysis of the IEEE Transactions on Intelligent Transportation Systems Literature
Abstract:
This paper presents a bibliographic analysis of the papers published in the IEEE Transactions on Intelligent Transportation Systems (T-ITS). We identify the most productive and high-impact authors, institutions, and countries/regions. We find that research on intelligent transportation systems is dominated by U.S. researchers and institutions and that China and Japan are the second most productive countries. According to this analysis, M. M. Trivedi, N. P. Papanikolopoulos, and P. A. Ioannou are the three most productive and influential authors in the IEEE T-ITS, whereas the Massachusetts Institute of Technology, Cambridge, the University of California, San Diego, and the University of Minnesota, Minneapolis, are three of the most productive and influential institutions in the IEEE T-ITS.
Autors: Li, L.;Li, X.;Li, Z.;Zeng, D. D.;Scherer, W. T.;
Appeared in: IEEE Transactions on Intelligent Transportation Systems
Publication date: Jun 2010, volume: 11, issue:2, pages: 251 - 255
Publisher: IEEE
 
» A Bidirectional Two-Axis Electrostatic MEMS Positioning System
Abstract:
We report on the design, fabrication, and testing of a bidirectional two-axis MEMS positioning system that is used to move a stage. Sandia National Laboratories' MEMS foundry process was utilized for the fabrication of the device; this process incorporates five layers of polysilicon and four sacrificial layers of silicon dioxide. The positioning assembly consists of a pin and slotted-arm arrangement, wherein the pin is constrained between the slotted arms and the positioning of the pin is achieved by identical electrostatic drives on both axes. The electrostatic drives consist of a comb drive interfaced with a compliant-mechanism-based distance multiplier. The stage is connected to a cantilever arm extending from the positioning pin. The crosstalk between the - and -axes was less than 0.3 through displacements of in both - and -directions. The displacement shows a quadratic relationship with the applied voltage. [2009-0213]
Autors: Sivakumar, G.;Matthews, J.;Subhani, M.;Dallas, T.;
Appeared in: Journal of Microelectromechanical Systems
Publication date: Jun 2010, volume: 19, issue:3, pages: 451 - 457
Publisher: IEEE
 

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