A Novel Mixed-Mode CCII-Based Filter

A new mixed-mode biquad circuit is presented. The circuit uses five second-generation current conveyors, seven resistors, and two grounded capacitors and can realize lowpass, highpass, bandpass , notch, lowpass notch, highpass notch and allpass responses from the same topology. The circuit can be driven by voltage or current and its output can be voltage or current. The parameters ωo and ωo/Qo enjoy independent electronic tunability. Simulation results are included

Extracting semantic relations from the Quranic Arabic based on Arabic conjunctive patterns

© 2017 The Authors There is an immense need for information systems that rely on Arabic Quranic ontologies to provide a precise and comprehensive knowledge to the world. Since semantic relations are a vital component in any ontology and many applications in Natural Language Processing strongly depend on them, this motivates the development of our approach to extract semantic relations from the Quranic Arabic Corpus, written in Arabic script, and enrich the automatic construction of Quran ontology. We focus on semantic relations resulting from proposed conjunctive patterns which include two terms with the conjunctive AND enclosed in between. The strength of each relation is measured based on the correlation coefficient. Finally, we evaluate the significance of this method by using hypotheses testing and Student t-test. The obtained results are very promising since we combine an accurate Arabic grammar with strong statistical techniques to prove the existence and measure the strength of this type of semantic relations

Successive interference cancellation using stage dependent decision functions

In this paper, we introduce the concept of stage-dependent decision functions. The latter exploit the improvement of the soft-decisions' reliability with increasing number of stages to take more hard-decisions and thus cancels more noise from stage to stage. We prove that if the stage-dependent thresholds can be optimized at each stage then the nonlinear SIC can approach the single user bound. Simulation results show significant BER improvement compared to the SIC using stage-independent decision functions

Modeling and Evaluation of Single Machine Flexibility Using Fuzzy Entropy and Genetic Algorithm Based Approach

International audienceFlexibility has long been recognized as a manufacturing capability that has the potential to impact mainly the competitive position of an organization. The entropy approach, which was extended from information theory, fell in handling problems with incomplete and uncertain data, because it depicts only the stochastic aspects included with measured observations. In order to get a global view, this work proposes a new approach based on fuzzy entropy concept. The development of the fuzzy model results in a set of nonlinear constrained problems to be solved using a metaheuristics method. The applicability of our approach is illustrated through a flexible manufacturing cell. By adopting such framework, both dimensions of uncertainty in system modeling, expressed by stochastic variability and imprecision, can be taken into consideration

A novel current-mode OTA-C universal filter Vol. 2, 2007, pp. 279-284

A novel current-mode biquad circuit is presented. The circuit uses two single-output-, one multiple-output-operational transconductance amplifiers (OTAs), two grounded capacitors and can realize lowpass, highpass, bandpass, notch, lowpass notch, highpass notch and allpass responses from the same topology. The parameters ωo and ωo/Qo enjoy independent electronic tunability. Simulation results are include

A new linear hybrid multiuser detector for CDMA systems

A new linear hybrid multiuser detection scheme is proposed. The structure cascades a linear successive interference cancellation detector and a linear parallel interference cancellation detector in order to extract the advantages of both. The convergence behavior of the hybrid scheme is investigated and moreover, the condition of convergence is determined. The proposed multiuser detector is compared to the other multiuser detectors in terms of complexity, delay, and other factors. Simulation results illustrate the superiority of the proposed

The effect of users' grouping on the linear group-wise successive interference cancellation detectors

We present a generalized linear multistage hybrid multiuser detector for the uplink channel in a CDMA system. We discuss new results that facilitate the analysis of multistage multiuser detectors. We validate our work by extensive simulation showing the convergence behavior of the hybrid multiuser detector for different users' grouping

Successive interference cancellation using stage dependent decision functions

In this paper, we introduce the concept of stage-dependent decision functions. The latter exploit the improvement of the soft-decisions' reliability with increasing number of stages to take more hard-decisions and thus cancels more noise from stage to stage. We prove that if the stage-dependent thresholds can be optimized at each stage then the nonlinear SIC can approach the single user bound. Simulation results show significant BER improvement compared to the SIC using stage-independent decision functions

A Chip-Level BSOR-based linear GSIC multiuser Detector for Long-Code CDMA Systems

In this work, we introduce a chip-level linear group-wise successive interference cancellation (GSIC) multi-user structure that is asymptotically equivalent to block successive over-relaxation (BSOR) iteration, which is known to outperform the conventional block Gauss-Seidel iteration by an order of magnitude in terms of convergence speed. The main advantage of the proposed scheme is that it uses directly the spreading codes instead of the cross-correlation matrix and thus doesn’t require the calculation of the cross-correlation matrix (requires 2NK2 floating point operations (flops), where N is the processing gain and K is the number of users) which reduces significantly the overall computational complexity. Thus it is suitable for long-code CDMA systems such as IS-95 and UMTS where the cross-correlation matrix is changing every symbol. We study the convergence behavior of the proposed scheme using two approaches and prove that it converges to the decorrelator detector if the over-relaxation factor is in the interval ]0, 2[. Simulation results are in excellent agreement with theory

A new ordering and grouping algorithm for the linear weighted group matched filter successive interference cancellation detector

A linear group-wise successive interference canceller in a synchronous code-division multiple-access system (CDMA) is considered in this paper. The proposed hybrid detector that combines successive and parallel cancellation techniques makes use of advantages offered by the two techniques. The convergence of the hybrid interference cancellation (HIC) detector is guaranteed by an adjustable parameter that depends upon the largest eigenvalue of the system's transition matrix. Since the largest eigenvalue is difficult to estimate, an upper bound is necessary for successful convergence. For this reason, a new upper bound for the maximum eigenvalue of the system's transition matrix was developed. Moreover, a new ordering and grouping algorithm that results in a higher convergence speed is proposed. Simulation results show that a significant improvement in performance is obtained using this technique