bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detecting moving and standing objects using cellular neural networks
Authors: Roska T. , Boros T. , Radványi A. , Thiran P. , Chua L. O. 
Published: July 2007

AbstractThe general framework of motion detection based on discrete time samples of the moving image is defined. Four types of motion detection problem are studied. the simplest one is a model resembling the famous Hubel‐Wiesel experiment with a cat's retina for detecting the motion of an object having a given speed in a given direction. the most complicated case is the determination of the vertical and horizontal velocity components of a moving image.Various cloning template sequences are proposed for detecting different types of motion. In the sampled mode the consecutive black‐and‐white snapshots are fed to the input and to the initial state nodes of the cellular neural network respectively. After the transients have decayed, the output gives the information necessary for detecting the presence or absence of a specific motion as well as for estimating the direction and magnitude of the velocity vector. In continuous mode the sampling process is eliminated by the use of delay‐type templates.Conditions are analysed under which the detection is correct. the circuit realization of some motion detectors is discussed and the use of a programmable dual‐CNN structure is proposed.
Very‐high‐output‐impedance cascode current sources/current mirrors/transresistance stages and their applications
Authors: Zarabadil Seyed R. , Ismail Mohammed 
Published: July 2007

AbstractA reconfigurable MOS/BiMOS cascode current source/transresistance stage with very high output impedance is presented in this paper. A cascode active feedback circuit has been employed to achieve such a high output impedance, which approaches the leakage resistance of a reverse‐biased junction, assuming that the MOS devices have a large channel length and do not exhibit the short‐channel effect. Through small‐signal analysis and SPICE simulation it is shown that the proposed current source/transresistance stage provides an output open‐circuit Thevinin voltage greater than 108 V. This is an increase of about four orders of magnitude as compared with the conventional cascode current source with the same output voltage range. For scaled technologies this current source/transresistance stage is shown to be ideal for practical high‐performance analogue circuit design. We have incorporated the current sources with active feedback in the output stage of a folded cascode op amp and obtained a large DC gain improvement without significantly affecting its high‐frequency/transient behaviour.
Determination of volterra transfer functions of non‐linear multiport networks
Authors: Larsen Torben 
Published: July 2007

AbstractA method is presented to determine frequency domain Volterra transfer functions of non‐linear multiport networks containing non‐linear multiport subsystems (elements). the method is based on an extension of the probing method to allow arbitrary (also commensurate) frequencies. A recursively based algorithm for the determination of Volterra transfer functions of non‐linear multiport networks is derived. A computer implementation of the method in a symbolic programming language is presented. This makes it possible to determine algebraic expressions of the Volterra transfer functions. Three examples are considered.
Elimination of limit cycles in direct form digital filters using error feedback
Authors: Laakso Timo I. 
Published: July 2007

AbstractThe elimination of zero‐input limit cycles in direct form filter sections using either a rounding or a magnitude truncation fixed‐point quantizer is considered. the well‐known criterion of Chang is reformulated for second‐order filter sections in a more practical form using the bilinear transformation. This enables graphical interpretation and quantitative analysis of the possible error feedback solutions for different pole locations.The synthesis of limit‐cycle‐free error feedback for second‐order filter sections is addressed in detail and several solutions are proposed. the error feedback coefficients are constrained to power‐of‐two values or to symmetric values so that the implementation is efficient, e.g. with signal processors. Different limit‐cycle‐free solutions are discussed with design examples and their round‐off noise properties are compared.The absence of limit cycles is related to the round‐off noise properties of the filter section. the main conclusion of the paper is that when the EF coefficients are appropriately chosen, low round‐off noise and the absence of limit cycles can always be accomplished at the same time. A particularly close correlation between limit cycles and roundoff noise is demonstrated with a rounding quantizer: a limit‐cycle‐free implementation always guarantees low roundoff noise. For most complex conjugate pole locations the converse relation also holds, i.e. low round‐off noise implies the absence of limit cycles.
On the realization of OTA‐C filters
Authors: Acar C. , Anday F. , Kuntman H. 
Published: July 2007

AbstractA synthesis procedure based on the signal flow graph is given for generating second‐order active filters using a minimum number of operational transconductance amplifiers and grounded capacitors. the pole quality factor and pole frequency sensitivities are studied for the proposed filters. Furthermore, the limitations on input signal amplitude are studied and a simple formula is derived for the input signal amplitude not causing clipping and slew‐rate‐limiting problems.
Analysis of quasi‐resonant converters using a state plane method
Authors: Baha B. 
Published: July 2007

AbstractIn this paper a state plane method has been used to analyse flyback and buck quasi‐resonant converters (QRCs). By using the state plane method, the DC voltage conversion ratio and the voltage and current stresses of the active switch, the diode and the resonant capacitor have been derived graphically. the DC voltage conversion ratio and the current stress of the active switch have been used to design QRC circuits. A flyback QRC has been designed, simulated, built and tested. the experimental results have been found to be in good agreement with PSpice simulations.
A 2d neural network with application to solving a class of matrix equations
Authors: Fa‐Long Luo , Yan‐Da Li 
Published: July 2007

AbstractThis paper presents a 2D neural network with application to solving a class of matrix equations. We show both analytically and by simulations that this neural network is guaranteed to be stable and to provide results arbitrarily close to the accurate solutions of the matrix equations within an elapsed time of only a few characteristic time constants of the network. Parameters such as the interconnection strengths and bias currents of this proposed network can be obtained from the known matrices of the matrix equations without any computations.
Synthesis of complex lossless two‐ports
Authors: Scarth Gordon B. , Martens G. O. 
Published: July 2007

AbstractA new synthesis algorithm is presented for the realization of a doubly terminated complex lossless two‐port from a given canonic set of scattering polynomials. the synthesis algorithm is based entirely on polynomial evaluations and thus polynomial arithmetic and routines for zero finding are not needed. the accuracy problem due to coefficient sensitivity is avoided. In particular, explicit knowledge of the intermediate polynomials is not required. the simplicity and functionality of the algorithm are based on a new representation of elementary sections given by a set of canonic parameters, namely the transmission zero of the section, the reflectance evaluated at the transmission zero and, for reciprocal sections, the return group delay evaluated at the transmission zero. A great deal of freedom is available, since transmission zeros with any multiplicity and located anywhere in the complex plane are realized independently. Also, complex networks composed exclusively of either inductors or capacitors as the dynamic elements are possible. an example is given to illustrate the robustness of the algorithm.
Finding all stable equilibria of cellular neural networks
Authors: Fajfar Iztok , Bratkovic Franc 
Published: July 2007

AbstractAn efficient algorithm is given for finding all stable equilibrium states of a cellular neural network. the method is based upon a new theorem concerning the network dynamics. the theorem implies the implementation of a simple sign test which, combined with a binary tree search, efficiently performs the task of searching the equilibria. Since the proposed algorithm uses information about the network architecture and dynamic behaviour, it exhibits two important advantages over other more general methods for searching the equilibria of resistive piecewise‐linear circuits. First, the regions which cannot possibly include stable steady states can be eliminated even before starting to perform the algorithm. Secondly, there is no need to solve any set of linear equations, which is usually the most tedious part of equilibrium‐searching methods.
A novel canonic, bipolynomial analogue filter configuration with a minimum number of common‐ground capacitors
Authors: Milić Mirko , Kandić Dragan 
Published: July 2007

AbstractWe proposed a novel canonic, multiple‐loop feedback, bipolynomial analogue filter configuration with a minimum number of common‐ground capacitors which contains same‐type active functional blocks. A detailed analysis of sensitivity criterion minimization is given and a comparison is made with other filter configurations.
Chua's circuit 10 years later
Authors: Chua Leon O. 
Published: July 2007

AbstractMore than 200 papers, two special issues (Journal of Circuits, Systems, and Computers, Vol.3, Nos. 1 and 2, 1993;IEEE Transactions on Circuits and Systems, Vol. 40 No 10, 1993), an international workshop on ‘Chua's Circuit: Chaotic Phenomena and Applications’ at NOLTA ‘93, and a book (R. N. Madan (ed.),Chua's Circuit: A Paradigm for Chaos, World Scientific, Singapore, 1993) on Chua's circuit have been published since its inception a decade ago. This review paper attempts to present an overview of these timely publications, almost all within the last six months, and to identify four milestones of this very active research area.An important milestone is the recent fabrication of amonolithicChua circuit. the robustness of this IC chip demonstrates that an array of Chua circuits can also be fabricated into a monolithic chip, thereby opening the floodgate to many unconventional applications in information technology, synergetics and even music.The second milestone is the recent global unfolding of Chua's circuit obtained by adding a linear resistor in series with the inductor to obtain acanonicalChua circuit—now generally referred to asChua's oscillator.This circuit is most significant because it is structurally thesimplest(it contains only six circuit elements) but dynamically the most complex among all non‐linear circuits and systems described by a 21‐parameter family of continuous odd‐symmetric piecewise‐linear vector fields.The third milestone is the recent discovery of several important new phenomena in Chua's circuits, e.g.stochastic resonance, chaos‐chaos‐type intermittency, 1/f noise spectrum, etc. These new phenomena could have far‐reaching theoretical and practical significance.The fourth milestone is the theoretical and experimental demonstration that Chua's circuit can be easilycontrolledfrom a chaotic regime to a prescribed periodic or constant orbit, or it can besynchronizedwith two or more identical Chua circuits operating in an oscillatory or chaotic regime. These recent breakthroughs have ushered in a new era wherechaosis deliberately created and exploited for unconventional applications e.g. secure communication.
Blind signal separation using cellular neural networks
Authors: Yang Tao 
Published: July 2007

AbstractIn this paper a two‐layer cellular neural network (CNN) is used to separate blind signals. the topological structures of the CNN and the inner parameters are presented. the first CNN layer functions as an adaptive filter which converges asymptotically to an equilibrium point in the mean. A stochastic stability model is used to find conditions under which cells in the first layer converge. Conditions leading to correct equilibrium solutions are also presented using this model. the second CNN layer functions as a signal separator. Simulations show that the CNN blind signal separator has strong robustness and works even better than the theory predicts.
A new analytical/iterative approach to statistical delay characterization of cmos digital combinational circuits
Authors: Aftab S. A. , Styblinski M. A. 
Published: July 2007

AbstractThis paper is believed to be one of the first attempts to statistically characterize signal delays of basic CMOS digital building blocks. Analytic expressions in terms of the transistor geometries and technological process variations are provided for fast delay computations, to be used for manufacturing yield optimization, delay variability reduction and general VLSI circuit design for quality. the proposed approach is novel in several ways: (1) It is a combination of an accurate, semi‐empirical MOS transistor model with the use of an efficient interpolation technique to link the non‐physical model parameters to the ‘designable’ and ‘noise’ factors. (2) It uses several newly developed analytical delay formulae where possible and simple iterative solutions where direct analytical solutions do not exist. (3) the resulting hybrid analytical/iterative models are tuned, if necessary, to enhance the overall statistical accuracy. (4) Local delays are combined together for the analysis of complex combinational VLSI circuits. (5) C‐code is generated for specific delay paths to further increase efficiency (improvement in analysis times by two to four orders of magnitude with respect to SPICE, with about 5%‐10% accuracy). Examples of statistical delay characterization are used to illustrate the high accuracy of the proposed approach in modelling the influence of the ‘noise’ parameters on circuit delay relative to direct SPICE‐based Monte Carlo analysis. the important impact of the proposed approach is that statistical evaluation and optimization of delays in much larger VLSI circuits will become possible.
Design of selective lowpass sampled‐data and digital filters exhibiting equiripple amplitude and phase error characteristics
Authors: Abo‐zahhad Mohammed , Henk Tamás 
Published: July 2007

AbstractA method is presented for the design of reciprocal reactant sampled‐data and digital filters exhibiting equiripple passband and stopband amplitude characteristics and approximating a linear phase characteristic such that the phase error response is equiripple too. the passband amplitude characteristic approximates unity transmission and the stopband amplitude characteristic approximates zero. Odd‐ and even‐degree cases are considered separately. the stopband amplitude response is controlled by an arbitrary number of finite transmission zeros together with two (one) zeros at infinity for even (odd) transfer functions. All the available degrees of freedom are used for controlling the filter performances. Thus the resulting solutions are selective and have good amplitude and phase characteristics. A comparison between our method and a recently published method shows that this approach has higher stopband loss and smaller phase error ripple with wider bandwidth.
Global dynamic behaviour of a three‐cell connected component detector cnn
Authors: Civalleri Pier Paolo , Gilli Marco 
Published: July 2007

AbstractThe global dynamic behaviour of a three‐cell connected component detector CNN described by the template [‐s, p, s] is addressed. In the casep‐1 >s> O the structure of the domains of attraction of the stable equilibria and the stable manifolds of the saddle points is represented by means of a suitable planar graph. In the cases>p‐ 1 > O it is shown that five stable and two unstable limit cycles occur. It is proved that one of the stable cycles lies entirely on the planex1= ‐x3whereas the others have the property that the second cell works only in the linear part of the output characteristic. Moreover, the domains of attraction of the stable cycles are found to be separated by the stable manifolds of the unstable equilibria (still existing fors>p‐ 1 > O ) and of the above two unstable limit cycles.
PastA&mdash;the characterization of the inherent fluctuations in the fabrication process for circuit simulation
Authors: Müller‐l Guntram E. 
Published: July 2007

AbstractFor worst‐case analysis, Monte Carlo analysis, yield optimization and design centring, the variations and correlations of the device model parameters in the electrical circuit simulation are of fundamental significance. This paper describes a method for the complete characterization of the inherent fluctuations in the fabrication process for the simulation in IC design. the emphasis is placed on analogue simulation owing to the complex connections between circuit design and technology and the multitude of devices with correlated parameters; nevertheless, statistical requirements for digital simulation can be fully covered.This characterization works with all technologies whether CMOS, BiCMOS or bipolar. the prerequisites are accurate nominal device model parameters for the circuit simulation and information about fabrication statistics, e.g. process control monitor measurements. A new approach with connection coefficients for the calculation of the correlation coefficients is presented. Dependent parameters can be easily defined through a connection hierarchy. With the presented approach the variations and correlations of model parameters for simulation can be generated from estimates or measurements of the fabrication process. Based on sensitivity analysis, the variations and correlations of design objectives can be estimated. This enables the designer to do circuit analysis and optimization (limit parameters, worst‐case distances) as well as Monte Carlo analysis.
Neuropsychological study of underweight and “weight‐recovered” anorexia nervosa compared with bulimia nervosa and normal controls
Authors: Bosanac Peter , Kurlender Simone , Stojanovska Lillian , Hallam Karen , Norman Trevor , McGrath Caroline , Burrows Graham , Wesnes Keith , Manktelow Tamsin , Olver James 
Published: July 2007

AbstractObjective:To compare executive, memory and visuospatial functioning of DSM‐IV anorexia nervosa (AN), bulimia nervosa (BN), and normal controls (NC).Method:A comparison of women involving: (i) 16 AN with body mass indices (BMI) ≤ 17.5 kg/m2; (ii) 12 AN with BMI > 18.5 kg/m2 for at least 3 months; (iii) 13 BN; and (iv) 16 NC participants was performed with groups of similar age and intelligence. Groups were assessed with EDE‐12, MADRS, HAMA, Cognitive Drug Research (CDR) battery, and Bechara tasks.Results:Significant impairments in CDR Power of Attention were present in underweight AN and BN participants. CDR Morse Tapping was significantly impaired in all clinical groups. The BN and weight‐recovered AN groups were significantly impaired on CDR immediate word recall. The BN group alone was significantly impaired on CDR delayed word recall.Conclusion:Attentional impairment is similar in AN and BN. Impaired motor tasks in AN persist after “weight‐recovery” and are similar to impairments in BN. BN may be discriminated from AN on word recall. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007
Anorexia nervosa and Raynaud's phenomenon: A case report
Authors: Yucel Basak , Uzum Ayse Kubat , Ozbey Nese , Kamali Sevil , Yager Joel 
Published: July 2007

AbstractObjective:To describe and discuss potential relationships between anorexia nervosa (AN) and Raynaud's phenomenon, the course and concurrent treatment of these two disorders as they appeared simultaneously, and a potential treatment modification entailed in such concurrent therapies.Background:Although Raynaud's phenomenon has been described during the course of AN, the associations and interactions between these two conditions are not clear.Method:We report the medical workup, treatment, and outcomes in a 19‐year old female patient who developed Raynaud's phenomenon following the onset of AN.Results:After treatment with nutritional rehabilitation, counseling, and individual and group therapy, the patient's weight, eating disorder‐related behaviors, and attitudes improved significantly. Raynaud's related symptoms improved, following treatment with a calcium channel blocker and antiaggregant therapy. In conjunction with nutritional efforts to treat the patient's long‐standing amenorrhea and osteopenia, the treatment team elected to also administer estrogen hormone in addition to oral calcium and vitamin D supplementation. Since oral contraceptives are to be avoided in patients with Raynaud's phenomenon who show clinical findings suggesting connective tissue disorder, the treatment team elected to treat this patient with transdermal hormone replacement therapy.Conclusion:The co‐occurrence of AN and Raynaud's phenomenon merits close and persistent follow‐up by a multidisciplinary team and may lead to alterations of usual therapeutic approaches. © 2007 by Wiley Periodicals, Inc.
Treatment perception in adolescent onset anorexia nervosa: Retrospective views of patients and parents
Authors: Halvorsen Inger , Heyerdahl Sonja 
Published: July 2007

AbstractObjective:To investigate perception of treatment in former patients with anorexia nervosa (AN) and their parents, and to determine whether this was related to outcome and treatment characteristics. Client satisfaction is important for treatment engagement and adherence.Method:Forty‐six (of 55) girls with adolescent onset AN, 33 mothers and 26 fathers participated in a follow‐up study conducted 8.8 (SD 3.3) years after start of treatment. The former patients were assessed using diagnostic interviews. Only nine participants (19%) had an eating disorder (ED) at follow‐up. Perception of treatment was assessed by questionnaires.Results:Parents reported having an overall positive perception of treatment. However, reports from former patients were significantly more negative than from the parents. In former patients, the “perception of therapists” total score and the items “therapists' knowledge of ED” and “usefulness of pediatric inpatient treatment” correlated with ED symptoms at follow‐up. The perception of therapists scores of the parents were not associated with the ED outcome of their daughters. More family therapy sessions were associated with the former patients' satisfaction with the therapists, while higher age at admission was associated with their mothers' satisfaction.Conclusion:In spite of good ED outcome, former patients were only moderately satisfied with their treatment, whereas parental satisfaction was high. © 2007 by Wiley Periodicals, Inc.