Electrical And Electronic Engineering Research Papers (original) (raw)

Coherent-population-trapping resonances within the degenerate two-level system of the F=2→F'=1 transition of the 87 Rb D1 line were investigated in an uncoated Rb vapor cell by means of level-crossing-type experiments. Tuning over the two-photon resonance is achieved sweeping a magnetic field around zero value. The influence of transverse magnetic fields on the amplitude and the width of the resonances, recorded in fluorescence and absorption, were investigated in the cases of excitation with linear, circular, and elliptical laser light polarization. A theoretical analysis was performed for the case of linearly polarized excitation, the results of which are in good agreement with the experiment.

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- Applied Mathematics, Physics, Magnetic field, Coherent Population Trapping

EuCARD-2 is a project partly supported by FP7-European Commission aiming at exploring accelerator magnet technology for 20 T dipole operating field. The EuCARD-2 collaboration is liaising with similar programs for high field magnets in the USA and Japan. EuCARD-2 focuses, through the workpackage 10 "Future magnets," on the development of a 10 kA-class superconducting, high current density cable suitable for accelerator magnets, for a 5 T stand-alone dipole of 40 mm bore and about 1 m length. After standalone testing, the magnet will possibly be inserted in a large bore background dipole, to be tested at a peak field up to 18 T. This paper starts by reporting on a few of the highlight simulations that demonstrate the progress made in predicting: dynamic current distribution and influence on field quality, complex quench propagation between tapes, and minimum quench energy in the multitape cable. The multiphysics output importantly helps predicting quench signals and guides the development of the novel early detection systems. Knowing current position within individual tapes of each cable we present stress distribution throughout the coils. We report on the development of the mechanical component and assembly processes selected for Feather-M2 the 5 T EuCARD2 magnet. We describe the CERN variable temperature flowing helium cold gas test system. We describe the parallel integration of the FPGA early quench detection system, using pickup

A simple semiempirical model of the electron beam generated by a pulsed cold cathode electron gun has been developed. The model describes analytically the observed self-focusing of the discharge and predicts the dynamical variation of the focal distance, in good agreement with experiments. This effect plays a major role in the determination of the effective duration of the energy pulse. The model was used to conduct simple calculations of energy thresholds for melting of solid materials, giving helpful insight on ranges of operation of this kind of electron gun for its application to material processing. A comparison with available experimental data for Mg 70 Zn 30 samples is given.

This paper describes the analysis of L-band radiometric measurement data gathered with the synthetic aperture radiometer HUT-2D during several ground-based and airborne measurement campaigns. The radiometric data are analyzed from the instrument's performance point of view, aiming to verify the theoretical performance of an instrument of this kind and to assess the performance of the HUT-2D radiometer system in particular. The data sets considered for the study consist of measurements of well-known natural targets, such as cosmic background radiation, and measurements of pure water scenes, the brightness temperature of which is possible to model based on in situ measurements. We define four figures of merit, which are applicable for synthetic aperture radiometers. These are radiometric resolution, image bias, pixel-to-pixel random error, and temporal stability. Then, we use the selected data sets to assess these in the case of HUT-2D. The experimental results are discussed and compared to the theoretical values, where applicable. Also, we discuss possibilities to improve the presented performance. The main results of this paper are the consolidated performance parameters of the HUT-2D instrument. We study and discuss the properties of the error components related to the technology in a general level, and study the scalability of the errors as a function of the measured targets. In particular, the stability of the direction-dependent error component is pointed out, and a mitigation guideline is proposed.

- by Alia Amira
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- Geophysics, Technology, Remote Sensing, Performance

It is well known that the presence of ions in the electron beam of a traveling wave tube (TWT) can lead to periodic variations in the output power, phase and the body (or helix) current. This has been referred to as ion noise or jitter. Recently, we have observed a different form of jitter, and while it is still observed as a small variation in the TWT output (typically 0.5 dB in power and 2 in phase), it is not periodic. We refer to this phenomenon as random jitter, since its random nature in time is a defining characteristic. Other characteristics include a relatively fast onset ( 1 ms) and slow ( 500 ms) recovery. It was found that random jitter was due to the spurious release of extremely small amounts of trapped gas inside the TWT. The source of the gas was identified and the problem was resolved. The observed level of fluctuations in power and phase had no effect on digital traffic and the small quantity of gas was found to have no measurable impact on cathode life.

- by Dan Goebel
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- Traveling wave tube, Electron Beam, Electrical And Electronic Engineering

A new method of designing nonimaging concentrators is presented and two new types of concentrators are developed. The first is an aspheric lens, and the second is a lens-mirror combination. A ray tracing of three-dimensional concentrators (with rotational symmetry) is also done, showing that the lens-mirror combination has a total transmission as high as that of the full compound parabolic concentrators, while their depth is much smaller than the classical parabolic mirror-nonimaging concentrator combinations. Another important feature of this concentrator is that the optically active surfaces are not in contact with the receiver, as occurs in other nonimaging concentrators in which the rim of the mirror coincides with the rim of the receiver.

- by Juan C Miñano
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- Mechanical Engineering, Optics, Ray Tracing, Applied Optics

Indices of heart rate variability (HRV) based on fractal signal models have recently been shown to possess value as predictors of mortality in specific patient populations. To develop more powerful clinical indices of HRV based on a fractal signal model, the study investigated two HRV indices based on a monofractal signal model called fractional Brownian motion and an index based on a multifractal signal model called multifractional Brownian motion. The performance of the indices was compared with an HRV index in common clinical use. To compare the indices, 18 normal subjects were subjected to postural changes, and the indices were compared on their ability to respond to the resulting autonomic events in HRV recordings. The magnitude of the response to postural change (normalised by the measurement

- by Paolo Castiglioni
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- Biomedical Engineering, Fractals, Electrocardiography, Heart rate variability

Traditionally, the location of lightning strike points has been determined by using the rolling sphere method, but recently the collection volume method (CVM) has also been proposed for the placement of air terminals on complex structures. Both these methods are empirical in nature and a more advanced model based on physics of discharges is needed to improve the state of affairs. This model is used to evaluate the striking distance from corners and air terminals on actual buildings and the results are qualitatively compared with the predictions of the rolling sphere method and the CVM. The results show that the striking distance not only depends upon the prospective return stroke current and the geometry of the building, but also on the lateral position of the downward leader with respect to the strike point. A further analysis is performed to qualitatively compare the lightning attraction zones obtained with the CVM and the leader inception zones obtained for a building with and without air terminals. The obtained results suggest that the collection volume concept overestimates the protection areas of air terminals placed on complex structures, bringing serious doubts on the validity of this method.

- by Vernon Cooray
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- Comparative Study, Lightning, Empirical Method, Complex Structure

Frequency modulation (FM) spectroscopy is a new method of optical heterodyne spectroscopy capable of sensitive and rapid measurement of the absorption or dispersion associated with narrow spectral features. The absorption or dispersion is measured by detecting the heterodyne beat signal that occurs when the FM optical spectrum of the probe wave is distorted by the spectral feature of interest. A short historical perspective and survey of the FM spectroscopy work performed to date is presented. Expressions describing the nature of the beat signal are derived. Theoretical lineshapes for a variety of experimental conditions are given. A signal-to-noise analysis is carried out to determine the ultimate sensitivity limits.

The goal of this paper is the development of control algorithms for the management of an automated warehouse system. As usual, the implementation of a control algorithm requires three preliminary steps: development of a reliable model; design of control procedures according to some optimality criteria; validation of these control procedures. As for modelling, a new level in the control architecture, namely an optimizer system, is introduced which performs real-time optimization thus simplifying the low-level control and improving the overall performance. In this context, the role of a detailed model of the whole warehouse is discussed and such a model is built up by using the colored timed Petri nets framework. As for control, we propose two control algorithms, derived under the simplifying continuity assumption of the rack locations, to optimize the operations of the cranes (moving within the aisles of the warehouse) and the operations of the shuttle (moving on a straight line placed between the aisles and the picking/refilling area), respectively. To evaluate the performance of the proposed control algorithms we define three different cost indices. As for the validation, extensive simulations are performed on the model in order to prove the effectiveness of the proposed control algorithms. A further validation of the algorithms has been performed on a test bed in order to take into account communication delays and computation times. Finally, the proposed architecture and control algorithms have been applied to a real plant. r

- by Yinxiao Yang
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- Nanowires, Resistivity, Conductivity, Chip

An applications-oriented review of optical parametric amplifiers in fiber communications is presented. The emphasis is on parametric amplifiers in general and single pumped parametric amplifiers in particular. While a theoretical framework based on highly efficient four-photon mixing is provided, the focus is on the intriguing applications enabled by the parametric gain, such as all-optical signal sampling, time-demultiplexing, pulse generation, and wavelength conversion. As these amplifiers offer high gain and low noise at arbitrary wavelengths with proper fiber design and pump wavelength allocation, they are also candidate enablers to increase overall wavelength-division-multiplexing system capacities similar to the more well-known Raman amplifiers. Similarities and distinctions between Raman and parametric amplifiers will also be addressed. Since the first fiber-based parametric amplifier experiments providing net continuous-wave gain in the for the optical fiber communication applications interesting 1.5-m region were only conducted about two years ago, there is reason to believe that substantial progress may be made in the future, perhaps involving "holey fibers" to further enhance the nonlinearity and thus the gain. This together with the emergence of practical and inexpensive high-power pump lasers may in many cases prove fiber-based parametric amplifiers to be a desired implementation in optical communication systems.

- by JIE LI
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- Quantum Physics, Optical Communication System, Optical physics, Wavelength Conversion

Two computing techniques to create an image of the radiating centres on an antenna or scatterer using Fourier optics is presented. Steve Inge ilieil on October 24, 2002 at the age of 61 after this article was submitted for publication. The reviewers accepted this article subject to revisions. Since that is not possible, this article is published as submitted. Uked more than to share his knowledge with others. Having said all that, in the end Steve was just a "good bloke" who will be sorely missed by many.

- by Deb Chatterjee
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- Electrical And Electronic Engineering

Technological innovation in all areas has led to the appearance in recent years of new metallic and pearlescent materials, yet no exhaustive studies have been conducted to assess their colorimetric capabilities. The chromatic variability of these special-effect pigments may largely be due to the three-dimensional effect of their curved shapes and orientations when they are directionally or diffusely illuminated. Our study examines goniochromatic colors using the optimal colors (MacAdam limits) associated with normal colors (photometric scale of relative spectral reflectance from 0 to 1) under certain conventional illuminants and other light sources. From a database of 91 metallic and interference samples and using a multigonio-spectrophotometer, we analyzed samples with lightness values of more than 100 and others with lightness values of less than 100, but with higher chromaticities than optimal colors, which places them beyond the MacAdam limits. Our study thus demonstrates the existence of chromatic perceptions beyond the normal solid color associated with these materials and independent of the light source. The challenge for future research, therefore, is to replicate and render these color appearances in current and future color reproduction technologies for computer graphics.

A k-plex is a selection of kn entries of a latin square of order n in which each row, column and symbol is represented precisely k times. A transversal of a latin square corresponds to the case k = 1. A k-plex is said to be indivisible if it contains no c-plex for any 0 < c < k. We prove that if n = 2km for integers k ≥ 2 and m ≥ 1 then there exists a latin square of order n composed of 2m disjoint indivisible k-plexes. Also, for positive integers k and n satisfying n = 3k, n = 4k or n ≥ 5k, we construct a latin square of order n containing an indivisible k-plex.

- by Judith Egan
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- Pure Mathematics, Electrical And Electronic Engineering

Feature extraction and dimensionality reduction are important tasks in many fields of science dealing with signal processing and analysis. The relevance of these techniques is increasing as current sensory devices are developed with ever higher resolution, and problems involving multimodal data sources become more common. A plethora of feature extraction methods are available in the literature collectively grouped under the field of Multivariate Analysis (MVA). This paper provides a uniform treatment of several methods: Principal Component Analysis (PCA), Partial Least Squares (PLS), Canonical Correlation Analysis (CCA) and Orthonormalized PLS (OPLS), as well as their non-linear extensions derived by means of the theory of reproducing kernel Hilbert spaces. We also review their connections to other methods for classification and statistical dependence estimation, and introduce some recent developments to deal with the extreme cases of large-scale and low-sized problems. To illustrate the wide applicability of these methods in both classification and regression problems, we analyze their performance in a benchmark of publicly available data sets, and pay special attention to specific real applications involving audio processing for music genre prediction and hyperspectral satellite images for Earth and climate monitoring.

- by Jeronimo Arenas-Garcia
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- Mechanical Engineering, Image Processing, Remote Sensing, Machine Learning

Over the last few years, IEEE 802.16 has been established as one of the most promising solutions for broadband wireless metropolitan area networks. In 2007, the standard was included as one of the radio access technologies for IMT-2000. The forthcoming version of the standard, IEEE 802.16m, is currently under evaluation by ITU as a radio technology for IMT-Advanced. In this paper we present a historical overview of the standard and provide a detailed technical discussion of the most relevant features introduced in the 2009 release and in the upcoming IEEE 802.16m. In particular, the downlink control signaling of these two versions is investigated in detail, and the results of a numerical analysis are illustrated for comparison purposes.

High-order modulation formats and advanced error correcting codes (ECC) are two promising techniques for improving the performance of ultrahigh-speed optical transport networks. In this paper, we present record receiver sensitivity for 107 Gb/s CO-OFDM transmission via constellation expansion to 16-QAM and rate-1/2 LDPC coding. We also show the single-channel transmission of a 428-Gb/s CO-OFDM signal over 960-km standard-single-mode-fiber (SSMF) without Raman amplification.

- by Simin Chen
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- Telecommunications, Optical physics, Microwaves, Optical Fibers

We have investigated the haematocrit dependence of the electrical parameters (relative permittivity and conductivity) of blood. The measuring set-up, composed of an impedancemeter (HP 4291A), an open-ended coaxial line and a temperature controlling set, was designed for dielectric measurements in the 1 MHz to 1 GHz frequency range. Measurements were performed on ex vivo animal (cow and sheep) blood at 37 • C. The two dielectric parameters appeared to be strongly dependent on the haematocrit. The permittivity versus frequency decreases then increases when the haematocrit decreases. The conductivity increases in the whole frequency range when the haematocrit decreases. Due to the lack of comparative data on the frequency range explored, we compare the dielectric profiles with those deduced from the Maxwell-Fricke theoretical model.

- by A. Rouane
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- Biomedical Engineering, Electrophysiology, Sheep, Blood

Changes in the dielectric breakdown field of polyimide (PI) films have been studied from 25 to 400 °C under dc ramps. Both the area (from 0.0707 to 19.635 mm 2 ) and thickness (from 1.4 to 6.7 µm) dependences of the dielectric breakdown field have been carried out using the Weibull distribution function. The 63%-breakdown field value (i.e. the -scale parameter) of PI shows a decrease with increasing area, thickness and temperature but always remains above 2 MV/cm. The -scale parameter of the distribution shows a typical decrease with increasing area, however, it exhibits an increase with increasing thickness. This 'curious' behavior is discussed on the basis of the percolation theory. No temperature-dependence is clearly observed. Moreover, physical interpretations are carried out using the pre-breakdown current analysis.

A new approach for the segmentation of local textile defects using feed-forward neural network is presented. Every fabric defect alters the gray-level arrangement of neighboring pixels, and this change is used to segment the defects. The feature vector for every pixel is extracted from the gray-level arrangement of its neighboring pixels. Principal component analysis using singular value decomposition is used to reduce the dimension of feature vectors. Experimental results using this approach illustrate a high degree of robustness for the detection of a variety of fabric defects. The acceptance of a visual inspection system depends on economical aspects as well. Therefore, a new low-cost solution for the fast web inspection using linear neural network is also presented. The experimental results obtained from the real fabric defects, for the two approaches proposed in this paper, have conÿrmed their usefulness.

- by AJAY KUMAR
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- Principal Component Analysis, Pattern Recognition, Neural Networks, Machine Vision

Partial discharge (PD) spectral response to variations in the supply voltage frequency was experimentally investigated through laboratory-based tests. The PD spectral content of each defect type responded uniquely to variations in the sinusoidal supply voltage frequency in the range 20 to 400 Hz. The findings are interpreted using the theory of space charge dynamics in PD mechanisms. Prospective diagnostic applications

- by Cuthbert Nyamupangedengu
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- Stress, Frequency Dependence, Partial Discharge, Diagnostic Test

Higher education institutions (HEIs) have been permeated by the technological advancement that the Industrial Revolution 4.0 brings with it, and forces institutions to deal with a digital transformation in all dimensions. Applying the approaches of digital transformation to the HEI domain is an emerging field that has aroused interest during the recent past, as they allow us to describe the complex relationships between actors in a technologically supported education domain. The objective of this paper is to summarize the distinctive characteristics of the digital transformation (DT) implementation process that have taken place in HEIs. The Kitchenham protocol was conducted by authors to answer the research questions and selection criteria to retrieve the eligible papers. Nineteen papers (1980–2019) were identified in the literature as relevant and consequently analyzed in detail. The main findings show that it is indeed an emerging field, none of the found DT in HEI proposals have ...

- by Lina Maria Castro benavides
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- Computer Science, Analytical Chemistry, Political Science, Medicine

Different classes of polymeric materials such as nanomaterials, sol-gel materials, conducting polymers, functional polymers and biomaterials have been used in the design of sensors and biosensors. Various methods have been used, for example from direct adsorption, covalent bonding, crossing-linking with glutaraldehyde on composites to mixing the enzymes or use of functionalized beads for the design of sensors and biosensors using these polymeric materials in recent years. It is widely acknowledged that analytical sensing at electrodes modified with polymeric materials results in low detection limits, high sensitivities, lower applied potential, good stability, efficient electron transfer and easier immobilization of enzymes on electrodes such that sensing and biosensing of environmental pollutants is made easier. However, there are a number of challenges to be addressed in order to fulfill the applications of polymeric based polymers such as cost and shortening the long laboratory synthetic pathways involved in sensor preparation. Furthermore, the toxicological effects on flora and fauna of some of these polymeric materials have not been well studied. Given these disadvantages, efforts are now geared towards introducing low cost biomaterials that can serve as alternatives for the development of novel electrochemical sensors and biosensors. This review highlights recent contributions in the development of the electrochemical sensors and biosensors based on

- by Mambo Moyo
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- Analytical Chemistry, Polymers, Sensors, Biosensor

We present a survey on five years of experiments of excimer laser irradiation of linen fabrics, seeking a coloration mechanism able to reproduce the microscopic complexity of the body image embedded onto the Shroud of Turin. We achieved a superficial, Shroud-like coloration in a narrow range of irradiation parameters. We also obtained latent coloration that appears after artificial or natural aging of linen following laser irradiations that, at first, did not generate any visible effect. Most importantly, we have recognized photochemical processes that account for both coloration and latent coloration.

- by Giuseppe Baldacchini and +2
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- Mechanical Engineering, Science and Religion, Holy Shroud of Turin, Shroud

The most crucial electro-magnetic and mechanical design aspects of an integrated electrical-motor-gas-compressor system in high speed and high power operation are presented. The electric motor type considered is a solid-rotor induction motor with properties of which are particularly well suited in high-speed operation. The effect of the electro-magnetic material properties of the solid rotor core material on the performance of the machine is discussed. Guidelines to improve the performance of the solid-rotor induction motor are given. Thermal design aspects of a solid-rotor induction motor are presented. The mechanical properties of a solid rotor are discussed. Bearing arrangements as well as the rotor dynamics of an integrated system are presented.

This paper presents a W-band receiver chipset for passive millimeter-wave imaging in a 65 nm standard CMOS technology. The system comprises a direct-conversion receiver front-end with injection-locked tripler and a companion analog back-end for Dicke radiometer. The receiver design addresses the high 1/f noise issue in the advanced CMOS technology. An LO generation scheme using a frequency tripler is proposed to lower the PLL frequency, making it suitable for use in multi-pixel systems. In addition, the noise performance of the receiver is further improved by optimum biasing of transistors of the detector in moderate inversion region to achieve the highest responsivity and lowest NEP. The front-end chipset exhibits a measured peak gain of 35 dB, 3 dB BW of 12 GHz, NF of 8.9 dB, while consuming 94 mW. The baseband chipset has a measured peak responsivity ( ) of 6 KV/W and a noise equivalent power (NEP) of 8.54 pW Hz 1 2 . The two chipsets integrated on-board achieve a total responsivity of 16 MV/W and a calculated Dicke NETD of 1K with a 30 ms integration time.

This paper presents laboratory results on the measurement system of a magnetic suspension bearing system for a jet engine rotor of an unmanned aerial vehicle (UAV). Magnetic suspension technology enables continuous diagnostics of a rotary machine and eliminates of the negative properties of classical bearings. This rotor-bearing system consists of two radial magnetic bearings and one axial (thrust) magnetic bearing. The concept of the bearing system with a magnetically suspended rotor for UAV is presented in this paper. Rotor geometric and inertial characteristics were assumed according to the parameters of a TS-21 jet engine. Preliminary studies of the measurement system of rotor engines were made on a laboratory stand with homopolar active magnetic bearings. The measurement system consisted of strain gauges, accelerometers, and contactless proximity sensors. During the research, strains were registered with the use of a wireless data acquisition (DAQ) system. Measurements were per...

- by Artur Kurnyta
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- Analytical Chemistry, Sensors, Electrical And Electronic Engineering

The sweep frequency response analysis (SFRA) is an analysis technique for detecting winding displacement and deformation (among other mechanical and electrical failures) on power and distribution transformers. Nowadays, there is an increasing interest in SFRA method because of its sensibility in detecting mechanical faults without opening the unit. SFRA as a diagnostic technique must integrate both the off-line measurements and the interpretation of the data in order to provide an assessment of the condition of the windings. However, guidelines for the measurement and record interpretation are not available. The evaluation is presently done by experts in the topic through the visual inspection or with the help of statistical parameters such as the correlation coefficient and the standard deviation. However, criteria like the limits of normal variation of the parameters, and the features observed in the records in the presence of a determined type of fault could not to coincide. Although, there are some proposals for making the interpretation more objective, neither of them integrate human expertise along with the different kind of parameters obtained from the evaluation of the records in a diagnostic model. This paper presents a survey on the alternatives in the measurement techniques and interpretation of SFRA measurements, describing some sources of uncertainty in applying this methodology.

Fermilab is developing and investigating different high-field magnet designs for present and future accelerators. The magnet R&D program was focused on the 10-12 T accelerator magnets based on Nb 3 Sn superconductor and explored both basic magnet technologies for brittle superconductors-wind-and-react and react-and-wind. Magnet design studies in support of LHC upgrades and VLHC are being performed. A series of 1-m long single-bore models of cos-theta Nb 3 Sn dipoles based on wind-andreact technique was fabricated and tested. Three 1-m long flat racetracks and the common coil dipole model, based on a singlelayer coil and wide reacted Nb 3 Sn cable, have also been fabricated and tested. Extensive theoretical studies of magnetic instabilities in Nb3Sn strands, cable and magnet were performed which led to successful 10 T dipole model. This paper presents the details of the Fermilab's high field accelerator magnet program, reports its status and major results, and formulates the program next steps.

- by R. Stanek
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- Materials Engineering, Condensed Matter Physics, Applied, Superconductors

In this note we generalize an upper bound given in Guggenheimer et al. (College Math. J. 26(1) (1995) 2) for the condition number of a matrix as a function of the determinant, the Frobenius norm and of k singular values. If no singular value is known it is possible to derive an upper bound for the condition number applying lower and upper bounds for the product of a subset of singular values.

- by Steve Shooter
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- Mechanical Engineering, Computer Model, Natural Frequency, Field Study

this paper compares the performances of the ATSC 8-VSB, the DVB-T COFDM, and the ISDB-T BST-OFDM digital television terrestrial transmission systems under different impairments and operating conditions. First, a general system level description is presented. It is followed by comparisons based on laboratory test results and theoretical analyzes. The differences in the system threshold definitions are discussed. In addition, a brief performance and implementation analysis is also presented for the three transmission systems under different network infrastructures. Whenever possible, the impact on the broadcasters or consumers is discussed. Possible performance improvements are also identified.

- by Bernard Caron and +1
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- Orthogonal Frequency Division Multiplexing (OFDM), Comparative Study, Performance Improvement, Multiplexing

This paper describes a probabilistic approach to the problem of recognizing places based on their appearance. The system we present is not limited to localization, but can determine that a new observation comes from a previously unseen place, and so augment its map. Effectively this is a SLAM system in the space of appearance. Our probabilistic approach allows us to explicitly account for perceptual aliasing in the environment—identical but indistinctive observations receive a low probability of having come from the same place. We achieve this by learning a generative model of place appearance. By partitioning the learning problem into two parts, new place models can be learned online from only a single observation of a place. The algorithm complexity is linear in the number of places in the map,
and is particularly suitable for online loop closure detection in mobile robotics.

- by Mark Cummins
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- Mechanical Engineering, Learning problems, Robotic, Mobile Robot
- by Serge Demidenko
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- Statistical Analysis, Computer Hardware, High Voltage, Stress Testing

This paper describes the highlights of presentations and discussions during the Third International BCI Meeting in a workshop that evaluated potential brain-computer interface (BCI) signals and currently available recording methods. It defined the main potential user populations and their needs, addressed the relative advantages and disadvantages of noninvasive and implanted (i.e., invasive) methodologies, considered ethical issues, and focused on the challenges involved in translating BCI systems from the laboratory to widespread clinical use. The workshop stressed the critical importance of developing useful applications that establish the practical value of BCI technology.

- by Femke Nijboer
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- Algorithms, Biomedical Engineering, Biotechnology, Electroencephalography

An adaptive and fast constant false alarm rate (CFAR) algorithm based on automatic censoring (AC) is proposed for target detection in high-resolution synthetic aperture radar (SAR) images. First, an adaptive global threshold is selected to obtain an index matrix which labels whether each pixel of the image is a potential target pixel or not. Second, by using the index matrix, the clutter environment can be determined adaptively to prescreen the clutter pixels in the sliding window used for detecting. The G 0 distribution, which can model multilook SAR images within an extensive range of degree of homogeneity, is adopted as the statistical model of clutter in this paper. With the introduction of AC, the proposed algorithm gains good CFAR detection performance for homogeneous regions, clutter edge, and multitarget situations. Meanwhile, the corresponding fast algorithm greatly reduces the computational load. Finally, target clustering is implemented to obtain more accurate target regions. According to the theoretical performance analysis and the experiment results of typical real SAR images, the proposed algorithm is shown to be of good performance and strong practicability.

This paper provides insight into the development of System Verilog Assertions standardization efforts. Specifically it covers the evolution from Accellera 3.1a version to its current state of standardization (the upcoming SVA2012 release). Insight into the new features, changes and the reasons for the same exposes users of SVA to the direction the standard is evolving.

- by Erik Seligman
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- History, Semantics, Computer Hardware, Hardware Description Languages

The paper examines electrophysiological activity produced by exposing the brains of laboratory animals to rectangular pulses of microwave energy. These results suggest that a microwave auditory phenomenon is evoked by a mechanism similar to conventional sound reception, and that the primary interaction site is peripheral to the cochlea. It is shown that the peak pressure due to thermal expansion is greater than the radiation pressure or electrostriction, and that the induced sound frequency is only a function of the size and acoustic property of the brain. Several suggestions were made for future research in microwave auditory effect and its health implications. ~~~~~~~ TITLE: Sensation and perception of microwave energy Authors: Michaelson, S. M. (Rochester Univ.)

- by James Lin
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- Biomedical Engineering, Electromagnetic Radiation, Electromagnetic Fields, Frequency

Reservoir simulations of CO* injection into a water flooded oil reservoir show that significant amounts of oil may be recovered, and a high storage capacity of CO, is obtained also through displacement of water. Simulated storage capacities for CO, injection into an aquifer vary in the range 13-68% pore volume, depending on the prevailing displacement mechanisms.

- by Erik Lindeberg
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- Conservation, Migration, Enhanced Oil Recovery, Reservoir Simulation

U nmanned aerial vehicles (UAVs) can be used to cover large areas searching for targets. However, sensors on UAVs are typically limited in their accuracy of localization of targets on the ground. On the other hand, unmanned ground vehicles (UGVs) can be deployed to accurately locate ground targets, but they have the disadvantage of not being able to move rapidly or see through such obstacles as buildings or fences. In this article, we describe how we can exploit this synergy by creating a seamless network of UAVs and UGVs. The keys to this are our framework and algorithms for search and localization, which are easily scalable to large numbers of UAVs and UGVs and are transparent to the specificity of individual platforms. We describe our experimental testbed, the framework and algorithms, and some results.

The implementation of FinFET structure in bulk silicon wafers is very attractive due to low-cost technology and compatibility with standard bulk CMOS in comparison with silicon-on-insulator (SOI) FinFET. SOI and bulk FinFET were analyzed by a three-dimensional numerical device simulator. We have shown that bulk FinFET with source/drain-to-body (S/D) junctions shallower than gate-bottom has equal or better subthreshold performance than SOI FinFET. By reducing S/D junction depth, fin width scaling for suppression of short-channel-effects (SCEs) can be relaxed. On-state performance has also been examined and drain current difference between the SOI and bulk FinFET at higher body doping levels has been explained by investigating enhanced conduction in silicon-oxide interface corners. By keeping the body doping low and junctions shallower than the gate-bottom, bulk FinFET characteristics can be improved with no increase in process complexity and cost.

- by Tomislav Suligoj
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- Low Cost Technology, Silicon on Insulator, Silicon Oxide, Silicon Wafer
- by Assongmo Claude Brice
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- Electrical Engineering, Photovoltaics, Power Electronics, Renewable Energy

Passive optical network (PON) is one of the most successful broadband access architectures being deployed worldwide. PONs provide high capacity, increased reach, and low-power consumption at a very reasonable cost, on par with the cost of DSL deployments today. This paper provides an overview of present and emerging PON technologies, and discusses PON's important role in the evolution of optical access from the architectural perspective. While describing the evolution of optical access architecture, we present two important integration options: optical+wireless access integration and metro+access integration. Potential PON capacity upgrades are discussed with special emphasis on achieving a seamless upgrade. We evaluate different PON evolution strategies in the context of next-generation PON, where gradual, demand-based migration demonstrates a number of significant benefits.

- by Pulak Chowdhury
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- Biomedical Engineering, Migration, Evolution, Broadband Networks

In this paper, we report on the integration challenges of the various component technologies developed towards the establishment of a framework for deploying an adaptive system of heterogeneous robots for urban surveillance. In our integrated experiment and demonstration, aerial robots generate maps that are used to design navigation controllers and plan missions for the team. A team of ground robots constructs a radio signal strength map that is used as an aid for planning missions. Multiple robots establish a mobile, ad-hoc communication network that is aware of the radio signal strength between nodes and can adapt to changing conditions to maintain connectivity. Finally, the team of aerial and ground robots is able to monitor a small village, and search for and localize human targets by the color of the uniform, while ensuring that the information from the team is available to a remotely located human operator. The key component technologies and contributions include (a) mission specification and planning software; (b) exploration and mapping of radio signal strengths in an urban environment; (c) programming abstractions and composition of controllers for multi-robot deployment; (d) cooperative control strategies for search, identification, and localization of targets; and (e) three-dimensional mapping in an urban setting.

- by chang boyoon
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- Mechanical Engineering, Situation awareness, Field Robotics, Adaptive System

In this study, we examine the psychological effects of 8K ultra-high-definition television (UHDTV) under daily TV viewing conditions. The design of 8K-UHDTV targets the realization of the "ultimate 2D image." 8K-UHDTV is already being used practically and the audience have reported experiencing a feeling of reality and presence. However, the benefits offered by 8K for daily TV viewing and the degree to which the design goals have been achieved have not been sufficiently verified. Hence, in this study, we verify them by investigating the popular impressions evoked by familiar images and their modulation with the viewing distance through subjective evaluation experiments and statistical analysis. The obtained results indicate that the impressions are enhanced by increasing the resolution from 4K to 8K, even at viewing distances beyond the design viewing distance, which are conventionally considered less effective. Thus, they confirm that 8K provides strong impressions over a wide viewing range. Furthermore, the relationship between higher-order impressions, such as "being-there" and "reality," and lower-order impressions is derived through multiple regression analysis. This provides insight into the enhancement of higher-order impressions in production and post-processing.